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Meniscal tear

137 citationsUpdated Sep 2026

Overview

Meniscal tears are the most common knee injuries necessitating surgery, with the medial meniscus affected approximately three times more often than the lateral meniscus [1]. Traumatic tears typically present in young patients with sports-related injuries, while degenerative tears occur in older patients with insidious onset [1]. Management is predicated on symptoms, as not all tears are symptomatic and many become asymptomatic over time [4]. Conservative treatment is appropriate for stable longitudinal tears less than 10 mm in length with less than 3 to 5 mm of displacement, short radial tears less than 3 mm, stable partial tears, and degenerative tears associated with significant osteoarthritis [4]. Nonsurgical management includes ice, NSAIDs, or physical therapy for range of motion and general strengthening [4].

Operative intervention is indicated for acute tears in younger patients, mechanical symptoms such as catching or locking, or failure of conservative measures [1]. Meniscal repair is the preferred strategy when feasible, with success rates of 80% to 90% reported in stable knees [1, 4]. Repair outcomes are significantly influenced by ACL status: success rates reach 90% with concurrent ACL reconstruction, 60% with an intact ACL, and drop to 30% in knees with a deficient ACL [1, 4]. Arthroscopic partial meniscectomy is indicated for radial, oblique, flap, horizontal cleavage, and complex tears, particularly in the avascular zone [4]. While meniscectomy has a low adverse event rate of 0.95%, it increases peak contact stresses and is associated with faster progression of osteoarthritis, particularly on the lateral side [1, 4, 36].

Meniscal root tears, which disrupt circumferential fibers and are functionally equivalent to total meniscectomy, require early surgical repair to restore hoop stresses and contact forces [1]. Meniscal allograft transplantation is reserved for skeletally mature patients younger than 50 years who remain symptomatic after meniscectomy, with long-term graft survivorship as high as 89% at 10 years in appropriately selected patients [4, 13]. Both meniscectomy and repair are safe procedures with low adverse event rates, though complications are associated with medical comorbidities, older age, and longer operative times [36]. Meniscal preservation should be the primary consideration, as repair offers the potential for reduced risk of osteoarthritis compared to resection [69, 75].

Anatomy & Pathophysiology

Gross Anatomy

The menisci are wedge-shaped fibrocartilaginous structures with a triangular cross section situated between the femoral condyles and tibial plateaus [128, 156]. The medial meniscus is semicircular or C-shaped, covering 50% to 60% of the medial tibial plateau surface [128] and 64% of the condyle surface [156]. It measures 10 mm in width and 3 to 5 mm in thickness [156], with a posterior horn approximately 11 mm wide and a slightly smaller anterior horn [128]. The lateral meniscus is more circular than the medial meniscus, featuring equally sized anterior and posterior horns [128]. It covers 84% of the condylar surface and measures 12 to 13 mm in width and 3 to 5 mm in thickness [156].

The medial meniscus is attached to the deep medial collateral ligament fibers and joint capsule, which limits its mobility [128]. The inferior aspect of its posterior horn attaches to the tibia via the meniscotibial or coronary ligament [128]. In contrast, the lateral meniscus has less continuous attachment to the capsule, conferring greater mobility [128]. The most common connection between the medial and lateral menisci is the transverse intermeniscal ligament, present in 60% to 94% of knees [128]. The meniscofemoral ligaments connect the posterior horn of the lateral meniscus to the medial femoral condyle [128]. The anterior meniscofemoral ligament of Humphrey courses anterior to the posterior cruciate ligament, while the posterior meniscofemoral ligament of Wrisberg courses posterior to it [128]. At the posterior lateral meniscal attachment, popliteomeniscal fascicles extend from the meniscus to the posterior capsule, creating the popliteal hiatus as the popliteus tendon becomes intra-articular [128].

Histology and Biochemistry

The meniscal substance consists of a solid extracellular matrix and water [128]. Fibrochondrocytes are the predominant cell type, producing an extracellular matrix primarily composed of type I collagen, with smaller amounts of types II, III, V, and VI collagen [128]. Proteoglycans, such as aggrecan, are key components that attract and bond to water, which comprises 65% to 75% of the meniscal volume [128]. Proteoglycans constitute 1% of the dry weight of the meniscus [156]. Type I collagen is most abundant in the superficial zones, providing tensile strength [128]. Conversely, larger concentrations of proteoglycans and water are found in the deeper zones, providing compressive strength [128].

Vascular Supply

The vascular supply to the menisci derives from the superior, middle, and inferior geniculate arteries [128]. The peripheral 10% to 30% of the meniscus is well vascularized by synovial and capsular branches [128], as are the anterior and posterior root attachments [128]. The outer third is designated the red/red zone and is well vascularized [128]. The middle third, or red/white zone, marks the border between vascularized and avascular regions [128]. The inner third, or white/white zone, is devoid of vascular supply [128]. Poorly vascularized portions receive nutrition through diffusion [128]. Approximately 50% of the meniscus is vascularized at birth, whereas only 10% to 25% remains vascularized in the adult [156]. Neural elements are predominantly located in the periphery of the anterior and posterior horns [128].

Biomechanics and Function

The menisci function in proprioceptive feedback, load distribution during physiologic loading, joint lubrication during motion, and maintenance of tibiofemoral joint stability and congruity [128]. In the deeper zones, collagen fibers are oriented circumferentially and stabilized by intermittent radially oriented tie fibers [128]. This orientation provides superficial tensile strength and absorption and dissipation of hoop stresses from axial loading during weight bearing [128]. The menisci transmit 50% of joint loads in knee extension and as much as 85% in flexion [128]. When the knee is in extension, up to 50% of the load is absorbed by the meniscus, with load-sharing increasing to 90% at 90° of knee flexion [156]. Beyond 90° of flexion, most force is transmitted to the posterior horns [156]. The lateral meniscus provides more biomechanical protection to the joint than the medial meniscus [156].

Complete meniscectomy increases articular cartilage contact stress by two to three times that experienced with an intact meniscus [156]. Removal of the inner third of the meniscus results in a 10% reduction in contact area and a 65% increase in contact stress on the articular cartilage [156]. A vertical tear of the medial meniscus causes increased contact area and maximum contact pressure in both the lateral and medial compartments [156]. A radial tear of the medial meniscus extending from the inner rim to the peripheral third, while preserving the peripheral third, has not been found to change maximum contact pressure and contact area [156]. However, a radial tear involving 90% of the medial meniscus results in a posterocentral shift in peak-pressure location [156]. Medial meniscus root tears result in peak articular cartilage contact pressure similar to that seen after complete meniscectomy [156]. Disruption of circumferential meniscal fibers leads to a loss of ability to transmit hoop stresses, with biomechanical effects approaching total meniscectomy [95]. Tears of the posterior medial meniscal root can increase contact pressure, external rotation, and lateral tibial translation [95]. A lateral root tear substantially decreases the contact area and increases contact pressure in the lateral compartment [95].

Lateral meniscus tears significantly impact in vivo knee kinematics across all three planes of motion [108]. Small lateral meniscus tears propagate over time regardless of ACL integrity, which might alter knee kinematics and resultant forces in the lateral meniscus as well as bony contact forces at the tibiofemoral joint [136]. Tear propagation significantly increased resultant forces in the lateral meniscus and bony contact forces in intact knees at specific flexion angles [191]. A longitudinal tear of the medial meniscus posterior horn in an ACL-deficient knee alters knee kinematics, particularly anterior-posterior tibial translation [180]. The meniscus status has a significant impact on knee kinematics in the ACL-deficient knee [119]. The integrity of the posterior root of the medial meniscus plays an important role in maintaining normal tibial-femoral joint contact mechanics [211]. The biomechanical consequences of a lateral meniscus root tear depend on the state of the meniscofemoral ligament [200]. Motion and weight loading of the knee can generate considerable tensile forces in repaired posterior medial meniscal roots [167].

Pathophysiology and Degeneration

At 10 to 20 years after diagnosis, on average, 50% of those with a diagnosed anterior cruciate ligament or meniscus tear have osteoarthritis with associated pain and functional impairment [7]. Osteoarthritis development in injured joints is caused by intra-articular pathogenic processes initiated at the time of injury, combined with long-term changes in dynamic joint loading [7]. Meniscal injury negatively affects knee biology within a very short period, with degenerative changes of the articular cartilage becoming apparent within a decade [43]. The relative risk of osteoarthritis after total meniscectomy is 14.0, with 4% cartilage loss per year [6]. The extent of subsequent joint degeneration is directly proportional to the amount of meniscal tissue removed [6].

Clinical studies with long-term follow-up of partial meniscectomy for meniscal tears found an increase in osteoarthritic changes within the affected compartment [3]. Partial meniscectomy for radial tears within 1 cm of the posterior horn insertion led to progression of osteoarthritis in 35% of patients at a mean 77-month follow-up [3]. At 5- to 7-year follow-up of 46 patients, one-third had progression of Kellgren-Lawrence grade 0 to 2 osteoarthritis to grade 3 or 4 [3]. Meniscal root tears are frequently unrecognized injuries that significantly alter knee biomechanics and kinematics, leading to accelerated degenerative changes [19].

The risk for symptomatic osteoarthritis progression following meniscal repair is 25% to 50% lower than that following arthroscopic partial meniscectomy but remains approximately twice as high as the general population [3]. In a systematic review of management for traumatic meniscal tears, both short-term and long-term revision surgery rates were higher after meniscal repair than after meniscectomy (16.5% versus 1.4% and 20.7% versus 3.9%, respectively) [3]. There were no plain radiographic degenerative changes in 78% of knees after meniscal repair, compared with 64% of knees after meniscectomy [3]. Nearly 80% of patients with arthroscopic meniscal repair had no osteoarthritis progression compared with only 40% of patients with meniscectomy at 8- to 10-year follow-up [3]. Approximately 96% of patients who underwent arthroscopic meniscal repair returned to their preinjury level of sports activity compared with only half of those who underwent a partial meniscectomy [3]. At 4-year follow-up, patients who underwent repair of a medial meniscal root tear had less progression of osteoarthritis and better clinical scores than those who underwent partial medial meniscectomy [3]. Preservation of the integrity of the articular cartilage on quantitative MRI has been associated with healed meniscal repairs [3].

Meniscal injury is identified on MRI in 31% of asymptomatic athletes and 91% of patients with knee osteoarthritis [6]. In the presence of osteoarthritis, débridement of stable meniscal tears is unlikely to provide lasting relief [6]. The cause of meniscal mucoid degeneration is usually attributed to endogenous and/or exogenous trauma [42]. Accumulation of mucopolysaccharides is suggested to be a response to nutritional deficiency [42]. Intrameniscal stromal degeneration is a nonspecific reaction to injury and a physiological condition in all knees [42]. The degenerative process of the meniscus is secondary to a vascular disturbance initiated by trauma or other causes [42]. Twenty-one of 26 articles in a systematic review implicated the role of the meniscus in the development of spontaneous osteonecrosis of the knee, in an association with either meniscal tears or its development after meniscectomy [242]. The medial meniscus and posterior meniscal root tears were implicated more frequently in the development of spontaneous osteonecrosis of the knee [242]. A traumatic meniscus tear can provoke pain by exerting a direct effect on the nociceptors of the meniscus and the synovial membrane and through elevated concentrations of intra-articular cytokines [247].

Classification

Arthroscopic Classifications

O’Connor: This classification categorizes meniscal tears into longitudinal, horizontal, oblique, and radial tears, along with variations including flap tears, complex tears, and degenerative meniscal tears [10].

Campbell: This system includes longitudinal tears, radial and oblique tears, horizontal cleavage tears, complex tears (defined as a combination of longitudinal and cleavage tears), tears associated with cystic menisci, and tears associated with discoid menisci [16].

ISAKOS: Designed to improve the consistency of arthroscopic classification and documentation, this validated assessment provides sufficient interobserver reliability for pooling data from international clinical trials evaluating meniscal tear treatment outcomes [143, 149]. While it offers a detailed description of lesions, intraobserver reliability did not reach optimum values despite an average of moderate agreement [179]. Surgeons can reliably classify meniscal pathology and agree on treatment, a factor important for multicenter trials [182]. Meniscal root tears are excluded from the ISAKOS tear type classification because they describe a location of tear rather than a pattern or appearance [92].

Tear Morphology and Patterns

Longitudinal: These vertically oriented tears run parallel to the edge of the meniscus and may extend completely or partially through its thickness [10]. A complete longitudinal tear that displaces an inner fragment into the intercondylar notch is termed a bucket-handle tear [10]. A peripheral vertical tear in zone I is a red-red tear, while a tear between zone I and II is a red-white tear [10]. Longitudinal tears are the most common type of meniscal tear, usually involving the posterior segment of either the medial or lateral meniscus [16]. They are also the most common pattern of meniscal tears in operative tibial plateau fractures [130].

Horizontal: More common in older patients, these tears result from shear forces that divide the superior and inferior surfaces of the meniscus [10]. They are more commonly seen in the posterior half of the medial meniscus or the midsegment of the lateral meniscus [10].

Oblique: These full-thickness tears run obliquely from the inner edge of the meniscus out into its body [10]. Transverse, radial, or oblique tears more commonly involve the lateral meniscus and are usually located at the junction of the anterior and middle thirds [16].

Radial: Vertically oriented tears extending from the inner edge toward the periphery, these can be complete or incomplete [10]. The radial tear configuration is almost unique to the lateral meniscus, occurring rarely in the medial meniscus [62].

Flap: Similar to oblique tears, flap tears usually possess a horizontal cleavage element rather than being purely vertical in orientation [10].

Complex and Degenerative: Complex tears may contain elements of longitudinal, horizontal, oblique, and radial tears and are more common in chronic meniscal lesions or older degenerative menisci [10]. Degenerative tears often refer to complex tears presenting with marked irregularity and complex tearing within the meniscus, most often seen in older patients [10]. Meniscus tear types and other findings at the knee joint, along with demographic variables, are associated with treatment for meniscus tears [59].

Special Tear Types

Posterior Root: A type of radial tear at the posterior root attachment of the meniscus [16]. Most meniscal root tears are radial tears, with a much smaller number being complex tears [92]. Posterior root tears of the medial meniscus are more commonly degenerative and occur in patients older than 40 [92]. Posterior root tears of the lateral meniscus are often associated with ACL tears in younger patients [92]. Anterior meniscal root tears have not been reported [92].

Ramp Lesion: A form of longitudinal tear at the menisco-capsular junction or the menisco-tibial attachment of the meniscus [16]. Ramp-like lateral meniscus tears are an infrequent lesion that must be differentiated from other subtypes of lateral meniscus tears in patients with concomitant ACL ruptures [199].

MRI Signal Grading

Grade 0: Defined as a normal intact meniscus [20].

Grade I: Defined as intrasubstance globular-appearing signal or a small focal area of hyperintensity not extending to the articular surface [20].

Grade II: Defined as linear increased signal patterns or areas of hyperintensity not extending to the articular surface [20]. In a multicenter study on 1,014 patients, only 17% of menisci with a grade 2 change were found to be torn at arthroscopy [91]. In a study on nondiscoid menisci, intrameniscal signal changes of grade 1 or 2 were correlated with a tear in only 11% of cases [91].

Grade III: Defined as abnormal signal or hyperintensity intersecting at least 1 articular surface (superior and/or inferior) of the meniscus, considered a definite meniscal tear that is arthroscopically confirmable [20]. In a study on nondiscoid menisci, 94% of menisci with linear or band-like signal intensity extending to the superior or inferior meniscal surface (grade 3) had a tear [91].

Other Considerations: A convolutional neural network model has the potential to be used in diagnosing the presence of meniscal tears and differentiating the types of meniscal tears [145].

Clinical Presentation

History and Symptoms

Meniscal tears are the most common knee injury necessitating surgery [1]. In adolescents and young adults, tears typically result from twisting injuries or changes in direction [26], whereas middle-aged and older adults often sustain tears from squatting or falling [26]. Degenerative tears usually occur in older patients with an insidious onset [1], and meniscal tears are unusual in patients younger than 10 years [26]. Acute tears frequently present with an effusion developing several hours after injury, distinct from the rapid swelling seen in anterior cruciate ligament (ACL) injuries [26]. Patients localize pain to the joint line or posterior knee [26] and may report mechanical symptoms such as locking or catching [26]. Chronic tears demonstrate intermittent effusions, often accompanied by mechanical symptoms [26].

Traumatic tears may be associated with pain onset during twisting or deep knee flexion [127], and occasionally an audible or palpable popping is reported [127]. Approximately one-half to two-thirds of patients report knee swelling [127]. Mechanical symptoms, including catching or frank locking, have been reported in 12% to 69% of patients and may suggest an unstable tear [127]. Up to 40% of patients experience a spontaneous onset of symptoms without a known inciting event [227]. Pain may diminish after injury but return with activity, associated with knee effusion [227]. Other symptoms include locking, giving way, and clicking sensations [227]. King reported pain in 82% of patients, giving way in 63%, locking in 43%, a sensation of clicking in the knee in 45%, and recurrent effusions in only 34% [227].

It is critical to correlate imaging with clinical findings, as meniscal tears are frequently found on MRI even when an expert clinician is confident that symptoms are not due to a meniscal tear [45]. Meniscal injury is identified on MRI in 31% of asymptomatic athletes [6] and in 91% of patients with knee osteoarthritis [6].

Physical Examination

Small joint effusions and joint line tenderness are common findings [26]. Palpation of the joint line may elicit tenderness at the location of a meniscal tear [127], with the posterior joint line being a common site given the prevalence of posterior horn tears [127]. Range of motion is typically normal, although longitudinal bucket-handle tears may block full extension [26]. Patients may report tightness in flexion if an effusion is present [26].

Special Tests: * McMurray and Apley tests: These manipulative maneuvers may produce a palpable or audible click with localized tenderness [26]. However, they are not specific for meniscal pathology [26]. In isolated meniscal tears, the McMurray test was accurate in 57% to 77% of patients [127]. * Thessaly test: The patient flexes the knee to 20° while standing on the affected extremity and twists in internal and external rotation [26]. This test often reproduces pain in patients with a meniscal tear [26] and was accurate in 61% to 80% of patients with isolated tears [127]. * Joint line tenderness: In isolated meniscal tears, this was an accurate test in 81% to 90% of patients [127].

Meniscus-specific tests should be interpreted for both pain and mechanical signs [127]. In patients with associated ligamentous or chondral injury, physical examination tests lose specificity for meniscal pathology [127]. However, the diagnostic performance of the McMurray test was largely preserved regardless of concomitant articular cartilage injury [105], whereas medial joint line tenderness showed reduced diagnostic performance in the presence of medial compartment cartilage injury [105]. Clinical examination by an experienced examiner using multiple meniscus tests is sufficient for a diagnosis of a meniscal tear [106]. The accuracy of the clinical diagnosis of meniscal tears has been demonstrated to be 70% to 75% in several large studies [26].

Imaging

Standard knee radiographs should be obtained to evaluate for bone injuries or abnormalities [26]. A weight-bearing radiograph is necessary to evaluate for osteoarthritis [26]. A right-to-left difference of at least 2 mm on weight-bearing radiographs represents a significant difference that will be verified by articular cartilage chondrosis at the time of arthroscopy [26].

MRI remains the noninvasive diagnostic procedure of choice for confirming meniscal pathology [26]. In grade III MRI classification, increased signal intensity reaches the articular surface of the meniscus [26]. The presence of an intra-meniscal signal extending to an articular surface and/or distortion of the normal shape represents a clinically significant tear [111]. MRI has demonstrated a high negative predictive value for meniscal tears, and a well-performed MRI of a knee with no meniscal pathology will rarely demonstrate a tear [26].

MRI Diagnostic Performance: * Medial meniscal tears: The sensitivity and specificity of 1.5-Tesla and 3.0-T MRI diagnosis, as confirmed with arthroscopy, were found to be 93% to 96% and 88% to 90%, respectively [127]. * Lateral meniscal tears: MRI was less sensitive (77% to 82%) but more specific (98% to 99%) [127]. * Posterior meniscal root tears: A study of 3.0-T MRI found sensitivity of 77% and specificity of 73% [127]. The decreased accuracy for root tears may be attributable in part to the radial orientation of many posterior root tears [127].

To be considered a relevant finding, a tear seen on MRI should correspond to the patient’s history and clinical examination findings [127]. 1.5-Tesla MRI accurately diagnoses ACL and medial meniscal tears and can reliably complete the diagnostic workup following physical examination, particularly in young adults [53]. The diagnostic validity of magnetic resonance imaging is similar for meniscal tears in acute knee trauma and in knee symptoms lasting over 6 months in young adults [52]. MRI contributes to enhancing the diagnostic accuracy of an unhealed meniscal repair when there are limited clinical signs of meniscal pathology [55]. Pre-operative tests and clinical findings are not conclusive for identifying a meniscal tear in symptomatic discoid menisci [47]. Factors affecting surgical decision making in meniscal injuries are based more or less only on the patient's clinical symptoms [142].

Investigations

History and Clinical Presentation

Swelling from an acute meniscal tear differs from an anterior cruciate ligament (ACL) injury, in which swelling develops rapidly within the first few hours [26]. Patients with meniscal injuries localize pain to the joint line or posterior knee and may describe mechanical symptoms of locking or catching [26]. In nonarthritic knees, focal joint line tenderness, effusion, and positive meniscal signs on physical examination may indicate meniscal pathology as a symptomatic source worthy of surgical intervention [6]. In the presence of osteoarthritis, mechanical symptoms such as locking or catching in combination with unstable meniscal tears on MRI warrant intervention [6]. Débridement of stable meniscal tears in the presence of osteoarthritis is unlikely to provide lasting relief [6].

Physical Examination

Manipulative maneuvers, including the McMurray and Apley tests, may produce a palpable or audible click with localized tenderness, but they are not specific for meniscal pathology [26]. Several large studies have demonstrated the accuracy of the clinical diagnosis of meniscal tears to be 70% to 75% [26].

Plain Radiography

Weight-bearing radiographs may include a weight-bearing AP or 45° PA flexion view [26].

MRI

Providers should use MRI sparingly and cautiously to confirm or rule out the attribution of knee pain to meniscal tear, as meniscal tears were frequently found on MRI even when an expert clinician was confident that a patient's knee symptoms were not due to a meniscal tear [45]. Pre-operative tests and clinical findings are not conclusive for identifying a meniscal tear [47]. Consequently, surgeons should be vigilant in identifying and repairing tears at the time of surgery because pre-operative tests are not conclusive [47]. The utility of MRI to rule out a medial meniscal tear significantly diminished in the young athletic population when >6 months passed between MRI and ACL reconstruction [185]. Surgeons should counsel patients preoperatively about the increased possibility of undiagnosed medial meniscus tears being found at the time of ACL reconstruction if greater than 6 months have passed from MRI to surgery [226]. Significant risk factors for false-negative MRI diagnosis of meniscal tears associated with ACL tears include short time from injury to MRI diagnosis, meniscal tear location within the posterior one-third, and peripheral longitudinal tear pattern [94]. Confusion between meniscal fraying and small tears is a major source of discrepancy between MRI and surgical findings [218]. Discriminating use of MRI offers major advantages in selected patients with unclarified meniscus lesions [215]. Based on reported MRI incidence of false positives with the medial meniscus and false negatives with the lateral meniscus, more costly care is provided when using MRI compared with needle arthroscopy [231]. Compositional sequences for MRI can allow for an evaluation of the biochemical properties of cartilage, meniscus, and ligament that offer further insight into pathology that may not be apparent on conventional clinical imaging [235].

MRI Grading and Interpretation

Grade 0: Indicates a normal intact meniscus [20, 26]. Grade I: Indicates intrasubstance globular-appearing signal or small focal area of hyperintensity not extending to the articular surface [20, 26]. Grade II: Indicates linear increased signal patterns or areas of hyperintensity not extending to the articular surface [20, 26]. Grade III: Indicates abnormal signal or hyperintensity intersecting at least 1 articular surface (superior and/or inferior) of the meniscus, which is considered a definite meniscal tear that is arthroscopically confirmable [20]. Alternatively, Grade III is defined as increased signal intensity that abuts the free edge of the meniscus, indicating a meniscal tear [26]. In a study on nondiscoid meniscus, intrameniscal signal changes (grade 1 or 2) were found to be correlated with a tear in only 11% of cases [91]. In a study on nondiscoid meniscus, 94% of menisci with linear or band-like signal intensity extending to the superior or inferior meniscal surface (grade 3) had a tear [91].

MRI Specificity for Tear Types and Locations

Magnetic resonance imaging is not an effective or efficient predictor of reparability of meniscal tears with the current arthroscopic criteria [223]. MRI is not always useful in predicting reparability of symptomatic isolated lateral semilunar meniscus tears [194]. Most of the symptomatic cases with normal MRI for isolated lateral semilunar meniscus tears were reparable [194]. For the medial meniscus, where horizontal and complex tear were more prevalent, 3-Tesla MRI shows a higher accuracy than for the lateral meniscus [240]. Meniscal root tears are frequently overlooked on MRI even when complete [92]. Direct attention to the roots on MRI improves radiologic diagnosis of meniscal root tears [92]. Radial root tears demonstrate a fluid cleft on coronal images and often exhibit a ghost meniscus on consecutive sagittal images [92]. Posterior root tears of the lateral meniscus often are associated with ACL tears in younger patients [92]. Radial tears in the root of the posterior horn of the medial meniscus may not be visible in about one-third of preoperative MRI scans [97]. Medial meniscus posterior root tear may occur in severe medial instability from trauma and is often missed on MRI diagnosis [233]. This type of anterior medial meniscus detachment and ACL tear injury is relatively rare and difficult to diagnose via MRI [60]. The accuracy of MRI in diagnosing discoid lateral meniscus is significantly lower in the presence of radial or longitudinal tears [239]. MRI is successful in determining the presence or absence of tears in discoid menisci; however, its ability to determine the tear type is questionable [181]. Meniscal morphologic changes on MRI are of value in predicting tears of the discoid lateral meniscus [91]. Physicians should suspect that an inverted-type discoid lateral meniscus tear is present during diagnosis and focus on the posterior horn to find the inverted sign on the MRI sagittal plane [219]. Considering the high number of false negatives of meniscal tears in preoperative MRI, high suspicion for specific tears should be used taking into account also the patient's remaining growth in skeletally immature patients with ACL rupture [234].

MRI for Healing Assessment

MRI criteria confirming meniscal healing after traumatic meniscal repair at 1 year include a change in the intrameniscal signal becoming nonfluid and moderate in intensity [241]. MRI criteria confirming meniscal healing after traumatic meniscal repair at 1 year include a reduction in tear diastasis to <1.5 mm [241]. MRI criteria confirming meniscal healing after traumatic meniscal repair at 1 year include a change in the signal morphology of the repaired meniscus [241].

Treatment

Non-Operative

Nonsurgical management is a first-line consideration for stable peripheral tears shorter than 5 to 10 mm in length [3], certain degenerative tears without mechanical symptoms [3], and tears associated with substantial osteoarthritis (Kellgren-Lawrence grade 3 or 4) [3]. In middle-aged patients with symptomatic non-obstructive meniscal tears, non-surgical management is appropriate as initial therapy [112]. Evidence indicates that physiotherapy is noninferior to arthroscopic partial meniscectomy for knee function over 24 months in patients with knee pain and nonobstructive tears [150]. Furthermore, arthroscopic surgery followed by exercise therapy is not superior to exercise therapy alone for non-traumatic, degenerative medial meniscal tears in most middle-aged patients [195]. Current evidence reports similar outcomes between arthroscopic partial meniscectomy and physical therapy for degenerative and nonobstructive symptoms [159], leading to the recommendation that non-operative treatment should always be started first, with surgery envisaged only after its failure [146]. Nonoperative management is also recommended for anterior horn tears noted on MRI in patients without mechanical symptoms and with a clinical examination inconsistent with pathologic meniscal condition [29]. Caution is advised when considering surgery for meniscal tears in patients with advanced radiographic osteoarthritis, even with frank mechanical symptoms [3]; these patients may be better candidates for initial nonsurgical management, with knee arthroplasty considered if this fails [3]. For pediatric patients, partial thickness tears comprising less than 50% of total meniscal thickness may be suitable for nonsurgical management [39]. An attempt at nonsurgical treatment may also be made for small (<1 cm), stable, longitudinal tears in the peripheral red-red zone [39]. Although most meniscal tears require operative intervention, a small percentage may be observed [17], including partial-thickness split tears arising from femoral or tibial surfaces that are stable to probing [17] and short (<10 mm) vertical peripheral tears that often heal sufficiently to resolve symptoms [17].

In patients with ACL tears treated non-operatively, secondary meniscal lesions may develop requiring delayed surgical management [135]. Patients with no meniscal damage at diagnosis should be aware that conservative management carries risks of further meniscal damage [48]. If surgery is decided for these patients, delay should be no longer than 6 months from diagnosis [48]. Surgeons should strongly encourage adherence to conservative modalities in patients awaiting operative reconstruction to reduce the risk of secondary meniscal pathology [220].

Operative

Indications: Irreparable unstable tears causing mechanical symptoms, such as a locked knee, can be treated with partial meniscectomy [3]. Tears in the avascular zone, such as radial or flap tears, are also candidates for partial meniscectomy [3]. Degenerative tears without substantial osteoarthritis can be treated with partial meniscectomy [3]. Tears that are not amenable to repair—excluding those that do not necessitate any treatment—are best treated with partial meniscectomy [1]. Partial-thickness tears, those <5 to 10 mm in length, and those that cannot be displaced >1 to 2 mm do not necessitate treatment [1]. General indications for meniscal repair include a tear between 1 and 4 cm [1], a vertical tear [1], a red-red tear [1], a meniscal root tear [1], and a patient younger than 40 years [1]. Tear types appropriate for repair include vertical longitudinal tears in the vascular zone of the meniscus [4] and displaced bucket-handle tears that remain in good condition once reduced [4]. Augmentation techniques, including fibrin clot, platelet-rich plasma clot, vascular access channels, and synovial rasping, may extend the indications for repair [1].

Surgical Approach / Technique: In general, complex, degenerative, and central/radial tears are treated with resection of a minimal amount of normal meniscus [1]. The objective of partial meniscectomy is to leave as much stable meniscal tissue as possible, with the goal of minimizing both the risk of recurrent meniscal tearing and that of future arthritic degeneration [39]. Preservation of as much meniscal tissue as possible minimizes future joint degeneration [3]. The goal of meniscal repair is to provide the meniscus with structural support and the ability to heal, thereby preserving meniscus integrity and restoring its function [3]. There has been a shift toward meniscal repair as the treatment of choice for meniscal tears when possible [3]. Surgeons should strive not to operate in most cases, but to protect, repair or reconstruct, in order to prevent early development of osteoarthritis by restoring the native structure, function, and biomechanics of the meniscus [87]. In a pediatric meniscus, a surgeon may push the limits of a meniscus repair as a tear in the avascular zone, time from injury to surgery, or tear size may not be contraindication to a repair [17]. Tears that are deemed irreparable by virtue of poor tissue quality, poor vascular supply, or some combination of factors are best treated by partial meniscectomy [39].

Other Considerations: Relative contraindications for meniscal repair include advanced degenerative articular cartilage damage [4], complex tears [4], poor meniscal tissue quality [4], and ACL deficiency [4]. In general, traumatic longitudinal tears occurring in the red/red (vascular) zone in patients younger than 30 years are believed to be most amenable to a successful repair [3]. Good results have also been demonstrated in red/white zone repairs in young patients [3]. Because of their blood supply, tears in the red/red zone are most likely to heal, followed by tears in the red/white zone [3]. White/white zone tears are avascular and thus have limited potential for healing [3]. Concomitant ACL reconstruction positively correlated with healing [3], and age younger than 30 years trended toward a positive correlation with healing [3]. Tears longer than 2 cm and smoking are negatively associated with healing rates [3]. Although the failure rate of meniscus repair may be greater in an unstable knee, meniscal repair is not contraindicated in a knee with a deficient ACL [82].

In several studies, 80% to 90% success rates with meniscal repairs have been reported [1]. It is generally accepted that the results of meniscal repair are best with acute peripheral tears in young patients undergoing concurrent ACL reconstruction [1]. In general, success rate is 90% when meniscal repair is performed in conjunction with an ACL reconstruction [1], 60% when performed in a knee with an intact ACL [1], and 30% when performed in a knee with a deficient ACL [1]. Clinical success rates for all meniscal repair techniques in stable knees are reasonable, ranging from 70% to 95% [4]. Several studies have demonstrated meniscal repair success greater than 90% when performed in conjunction with an ACL reconstruction [4]. Meniscal repair is a viable alternative to resection in many clinical situations, with success rates exceeding 80% when performed with anterior cruciate ligament reconstruction [41]. In appropriately selected patients, meniscal repair can deliver improved subjective outcomes with comparable reoperation rates and the potential for reduced risk of osteoarthritis over time versus meniscectomy [69]. The long-term survival rate of repaired menisci was 91% [73]. A meniscectomy after meniscal repair is performed infrequently, supporting the notion that repairing a meniscus is a safe and effective procedure in the long term [11].

Satisfactory clinical outcomes are achievable for radial meniscal tear repair at short-term follow-up [35]. At mean 10-year follow-up, significant clinical improvements and high rates of satisfaction were observed for radial meniscal tear repair [86]. Meniscal preservation with repair of radial tears results in improved short-term clinical outcomes, however, long-term outcomes remain unknown [5]. Current consensus is that meniscal root tears should be clinically recognized, and strong consideration should be given to surgical repair in selected cases by utilizing techniques designed to anatomically restore the root, maximize meniscal function, and preserve the health of the knee joint [12]. The current level 3 and 4 evidence suggests that arthroscopic repair may result in slower progression of radiological deterioration compared with meniscectomy and nonoperative management for acute meniscus root tears [93]. Meniscus repair should be adopted as the preferred initial intervention for medial meniscus root tears to prevent knee osteoarthritis [165]. Satisfactory clinical outcomes are achievable at short to midterm follow up with both inside-out and all-inside repair of bucket handle meniscal tears in appropriately selected patients [160].

Both the short-term and long-term revision surgery rates were higher after meniscal repair than after meniscectomy (16.5% versus 1.4% and 20.7% versus 3.9%, respectively) [3]. The failure and revision surgery rate was found to be higher for medial than lateral meniscal repairs at short-term and medium-term follow-up [3]. Magnetic resonance imaging is unsuitable for diagnosis of the healing process of a repaired meniscus [73].

Factors that seem to predict better long-term function following arthroscopic partial meniscectomy include age younger than 40 years, normal lower extremity alignment, minimal arthritic changes noted at the time of arthroscopy, and a single fragment tear [4]. A 50% finding of Fairbank’s changes on radiographs, including osteophytes, flattening of the femoral condyles, and joint space narrowing, was observed in studies of arthroscopic partial meniscectomy [4]. At 5- to 7-year follow-up of 46 patients, one-third had progression of Kellgren-Lawrence grade 0 to 2 osteoarthritis to grade 3 or 4 osteoarthritis after partial meniscectomy [3]. Although the modified Lysholm Knee Questionnaire score often significantly improved after partial meniscectomy, only 56% of patients reported pain improvement [3]. Comprehensive evidence from randomized controlled trials showed no clear benefit of arthroscopic meniscectomy over nonoperative treatment for a significant proportion of patients with degenerative tears [126]. A rigorous randomized controlled trial that compared arthroscopic partial meniscectomy with sham surgery found similar improvement in both arms, with no advantage of arthroscopic partial meniscectomy over sham surgery [161]. For patients who do not respond to physical therapy, arthroscopic meniscectomy does appear to be a successful second-line treatment of degenerative tears [126]. Nonoperative management of degenerative meniscal tears is worth a try [168].

Complications

General Surgical Complications

Meniscectomy and meniscal repair are safe procedures with low adverse event rates of 0.95% and 1.4%, respectively [36]. Complications are associated with medical comorbidities, older age, and longer operative times [36]. Neurovascular protection is critical; saphenous nerve branches must be protected during medial repairs, and the peroneal nerve during lateral repairs [1, 2]. All-inside techniques may offer reduced neurovascular risk compared to other methods [4]. In pediatric patients, all-inside repair techniques are generally recommended to be avoided in younger children due to the increased risk of direct injury to the popliteus neurovascular bundle [39].

Repair Failure and Revision

The overall meniscus repair failure rate remains 19% in long-term studies [71], with one-third of repairs undergoing reoperation within five years [243]. Long-term revision surgery rates are higher after meniscal repair (20.7%) than after meniscectomy (3.9%) [3, 6]. Risk factors for failure of arthroscopic repair with an absorbable screw include chronicity of injury, tear location more than 3 mm from the meniscosynovial junction, and medial meniscus side [251]. Tears longer than 2 cm and smoking are negatively associated with healing rates [3]. Age of 40 years or older is not associated with an increased risk of failure at 5 years, although a shorter time to failure was noted in this cohort [100]. Failure risk does not differ between men or women at mid-term follow-up [151]. Success rates vary by ACL status: 90% with concomitant ACL reconstruction, 60% with an intact ACL, and 30% with a deficient ACL [1, 2]. Patients may report slightly worse subjective knee function at 6- and 12-month follow-up compared to meniscal resection [81]. Clinical success rates for repairs using bioabsorbable polylactic acid arrows dropped from 91% at a mean 2.3 years to 71% at a mean 6.6 years [96].

Osteoarthritis and Joint Degeneration

Peak contact articular cartilage stresses increase proportionally to the amount of meniscus removed during partial meniscectomy [4]. Long-term follow-up of partial meniscectomy shows an increase in osteoarthritic changes within the affected compartment [3]. Despite a 50% finding of Fairbank’s changes on radiographs, studies demonstrate greater than 80% satisfactory function at minimum 5-year follow-up after arthroscopic partial meniscectomy [4]. Meniscal repair is associated with lower progression to knee osteoarthritis at approximately six years compared to partial meniscectomy [101]. There is a lack of evidence to support a protective role of repair or reconstructive surgery of the anterior cruciate ligament or meniscus against osteoarthritis development [7]. While arthroscopic repair for isolated longitudinal injuries in stable knees yields favorable functional results, its effects on secondary osteoarthritis risk are not clear [163]. Meniscal and articular cartilage pathology had a larger impact at 6 years compared to 2 years, with medial pathology significantly diminishing activity levels [103].

Transplantation Complications and Outcomes

The overall failure rate for meniscal allograft transplantation, defined as conversion to total knee arthroplasty, ranges from 10% to 29% in long-term follow-up [6]. Meniscal allografts provided subjective improvement at 20 years, with an overall graft survivorship of 56.2% [32]. In appropriately selected patients, long-term graft survivorship has been reported as high as 89% at 10 years [13]. Meniscal transplantation is clinically effective for symptomatic meniscal deficiency, though survivorship is significantly lower in patients with full-thickness chondral loss [30]. Both graft survival and patient-reported outcomes are associated with age, with lower outcomes in patients younger than 35 years and worse survival in patients older than 50 years [14]. Meniscus scaffolds represent a safe and viable treatment for symptomatic partial meniscus defects, providing significant clinical improvement at short and midterm follow-up with an acceptable failure and complication rate [66].

Recovery

Light activity (weeks): The provided evidence does not specify a typical week range for desk work, driving, or light activities of daily living.

Full activity (months): The provided evidence does not specify a month range for the return to manual work, sport, or full range of motion and strength.

Complete recovery / outcome plateau (months): The provided evidence does not specify a month range for the stabilization of pain, strength, and final functional outcomes.

Rehabilitation protocol: The provided evidence does not detail physical therapy phasing, immobilisation duration, weight-bearing or range of motion progression, or sling and brace removal timing.

Functional milestones: Meniscal repair and partial meniscectomy both improved patient-reported outcomes and activity levels at short-term follow-up [31]. While patients with meniscal repair may have slightly worse subjective knee function at both 6- and 12-month follow-up compared with meniscal resection [81], meniscal repair has been shown to improve long-term functional scores when compared with meniscectomy [154].

Other Considerations: The overall meniscus repair failure rate remains nineteen percent in long-term studies [71]. Despite the chronic nature of lesions, results suggest good short-term clinical and anatomic outcomes post-repair [67]. Open repair of horizontal meniscal tears in young adults leads to good subjective and objective results in the short term, which are maintained in the long-term [77]. Good long-term outcomes can be obtained in patients up to over 12 years after combined ACL reconstruction and meniscal repair [79]. Very good clinical long-term outcomes are observed following meniscal repair in a pediatric population [83]. The long-term evaluation of anterior cruciate ligament–reconstructed knees with concurrent successful meniscal repairs demonstrated a low rate of radiographic arthritis [192]. Meniscal repair is associated with a lower progression to knee osteoarthritis at approximately six years of followup compared to partial meniscectomy [101].

Positive outcomes for meniscal allograft transplantation are most likely to be achieved when performed in appropriately selected patients, with studies reporting long-term graft survivorship as high as 89% at 10 years and significant improvements in multiple patient reported outcome measures [13]. Meniscal allografts were able to provide subjective improvement at 20 years after surgery and while not as durable as the native meniscus, the overall graft survivorship was 56.2% after implantation [32]. Meniscal allograft transplantation is a viable and effective surgical option for the painful meniscus-deficient knee, with good survivorship and functional outcomes in the medium to long term [76].

Timing of intervention significantly influences meniscal integrity and healing potential. Delay in surgery for >1 year was associated with increased risk of medial meniscal tear [102]. A delay from the injury to the surgical procedure was associated with a 3% weekly increased risk of medial meniscal injury for male patients, but not for female patients [104]. Time from ACL injury to reconstruction of 3 months was strongly associated with medial meniscal injuries and irreparable medial meniscal tears at primary ACLR [253]. In female patients who experienced an ACL injury, a delay in surgery greater than 12 months is associated with a gradual increase in the risk of nonrepairable medial meniscal tear; this risk becomes statistically significant after 24 months [254]. Conversely, delaying ACLR to 8 to 12 weeks after injury may optimize the potential for spontaneous healing in lateral meniscus injuries, particularly posterior horn longitudinal and radial tears, potentially increasing meniscal healing rates by 1.5 to 2.5 times compared with early intervention [255].

Key Evidence

• [L1] Meniscal preservation with repair of radial tears results in improved short-term clinical outcomes, however, long-term outcomes remain unknown. [5] (10.1016/j.arthro.2016.03.029)
• [L4] [7] (10.1177/0363546507307396)
• [L5] Knee meniscal repair has a success rate of approximately 80% in both men and women, and meniscal repair is a critical procedure for maintaining long-term knee health. [8] (10.1016/j.arthro.2019.12.017)
• [L5] Meniscal repair should be considered whenever possible, with strategies specific to tear type and patient features. [9] (10.5435/jaaos-d-21-01153)
• [L3] A meniscectomy after meniscal repair is performed infrequently, supporting the notion that repairing a meniscus is a safe and effective procedure in the long term. [11] (10.1177/0363546513503444)
• [L5] Current consensus is that meniscal root tears should be clinically recognized, and strong consideration should be given to surgical repair in selected cases by utilizing techniques designed to anatomically restore the root, maximize meniscal function, and preserve the health of the knee joint. [12] (10.1016/j.csm.2011.08.013)
• [L5] Positive outcomes for meniscal allograft transplantation are most likely to be achieved when performed in appropriately selected patients, with studies reporting long-term graft survivorship as high as 89% at 10 years and significant improvements in multiple patient reported outcome measures. [13] (10.1007/s00167-020-06058-6)
• [L3] Both meniscal allograft survival and patient-reported outcomes were associated with age, with lower outcomes in patients younger than 35 years and worse survival in patients older than 50 years. [14] (10.1007/s00167-020-06276-y)
• [L5] Meniscal root tears are frequently unrecognized injuries that significantly alter knee biomechanics and kinematics, leading to accelerated degenerative changes. [19] (10.1177/0363546514524162)
• [L3] [20] (10.1016/j.asmr.2024.101065)
• [L4] Meniscal surgery can be performed with the correct timing and the proper indication even in the presence of early osteoarthritis, as there is a relevant regenerative potential of the meniscus and the surrounding cartilage that should be taken into account. [28] (10.1007/s00167-016-4069-2)
• [L4] We recommend nonoperative treatment of anterior horn tears noted on MRI among patients without mechanical symptoms and whose clinical examination is inconsistent with the presence of a pathologic meniscal condition. [29] (10.1177/03635465020300020701)
• [L3] Meniscal transplantation is clinically effective in treating patients with symptomatic meniscal deficiency, with survivorship significantly lower in patients with full-thickness chondral loss. [30] (10.1007/s00167-019-05459-6)
• [L4] Meniscal repair and partial meniscectomy improved patient-reported outcomes and activity levels at short-term follow-up. [31] (10.1177/2325967120969220)
• [L4] Meniscal allografts were able to provide subjective improvement at 20 years after surgery and while not as durable as the native meniscus, the overall graft survivorship was 56.2% after implantation. [32] (10.1016/j.arthro.2020.04.029)
• [L5] The authors argue that evaluating the usefulness of meniscectomy is flawed due to insufficient stratification of meniscal tear characteristics, and that clinical practice guidelines may be flawed if they recommend against treatments that benefit specific patient subgroups despite Level I evidence showing safety and efficacy. [34] (10.1016/j.arthro.2014.03.016)
• [L3] Satisfactory clinical outcomes are achievable for radial meniscal tear repair at short-term follow-up. [35] (10.1177/0363546518786035)
• [L5] Both meniscectomy and meniscal repair are safe surgical procedures with low adverse event rates (0.95% and 1.4%, respectively), but complications are associated with medical comorbidities, older age, and longer operative times. [36] (10.1016/j.arthro.2023.12.017)
• [L4] Meniscal repair is a viable alternative to resection in many clinical situations, with success rates exceeding 80% when performed with anterior cruciate ligament reconstruction. [41] (10.5435/00124635-200205000-00004)
• [L4] [42] (10.1007/s00167-003-0412-5)
• [L4] Meniscal injury has a negative effect on the biology of the knee within a very short period of time, with degenerative changes of the articular cartilage becoming apparent within a decade. [43] (10.1016/j.csm.2019.08.001)
• [L3] Meniscal tears were frequently found on MRI even when an expert clinician was confident that a patient's knee symptoms were not due to a meniscal tear, indicating that providers should use MRI sparingly and cautiously to confirm or rule out the attribution of knee pain to meniscal tear. [45] (10.1186/s12891-016-1010-2)
• [L3] Pre-operative tests and clinical findings are not conclusive for identifying a meniscal tear, and surgeons should be vigilant in identifying and repairing tears at the time of surgery. [47] (10.1007/s00167-020-06375-w)
• [L3] Patients with no meniscal damage at diagnosis should be aware that conservative management carries risks of further meniscal damage; if surgery is decided, delay should be no longer than 6 months from diagnosis. [48] (10.1007/s00167-008-0622-y)
• [L4] According to current standard indications, 34.9% of all meniscal injuries offer the potential for repair, rising to 55.6% when accompanied by anterior cruciate ligament damage. [49] (10.1016/j.arthro.2018.08.051)
• [L2] The diagnostic validity of magnetic resonance imaging is similar for meniscal tears in acute knee trauma and in knee symptoms lasting over 6 months in young adults. [52] (10.1177/0363546508329543)
• [L3] 1.5-Tesla MRI accurately diagnoses ACL and medial meniscal tears and can reliably complete the diagnostic workup following physical examination, particularly in young adults. [53] (10.1186/s12891-021-04011-3)
• [L3] The clinical relevance of this finding is that MRI contributes to enhancing the diagnostic accuracy of an unhealed meniscal repair when there are limited clinical signs of meniscal pathology. [55] (10.1007/s00167-019-05523-1)
• [L5] Knee partial meniscectomy has limited benefit for nonobstructive meniscal tears, but it is necessary to determine if included patients have osteoarthritis to establish indications for surgical versus nonsurgical treatment. [57] (10.1016/j.arthro.2016.07.013)
• [L3] Meniscus tear types and other findings at the knee joint, along with demographic variables, are associated with treatment for meniscus tears. [59] (10.1177/23259671251397648)
• [L4] This type of meniscus injury is relatively rare and difficult to diagnose via MRI; early ACL reconstruction is recommended to avoid progression of meniscal injury and facilitate repair. [60] (10.1007/s00167-006-0255-y)
• [Paper] Meniscus scaffolds represent a safe and viable treatment for symptomatic partial meniscus defects in the well-aligned, stable knee with limited cartilage degeneration, providing significant improvement of clinical outcome at short and midterm follow-up with an acceptable failure and complication rate. [66] (10.1016/j.csm.2019.08.011)
• [L4] The results found suggest good short-term clinical and anatomic outcomes post-repair of meniscal lesions, despite their chronic nature. [67] (10.1007/s00167-013-2552-6)
• [L5] In appropriately selected patients, meniscal repair can deliver improved subjective outcomes with comparable reoperation rates and the potential for reduced risk of osteoarthritis over time versus meniscectomy. [69] (10.1016/j.arthro.2024.11.058)
• [L1] The overall meniscus repair failure rate remains nineteen percent in long-term studies. [71] (10.1007/s00167-021-06770-x)
• [L3] The long-term survival rate of repaired menisci was 91%, and magnetic resonance imaging is unsuitable for diagnosis of the healing process of a repaired meniscus. [73] (10.1177/03635465990270011001)
• [L5] Meniscal preservation should always be the first thought over partial meniscectomy, with a focus on extending indications, using biologic enhancement, and addressing specific tear types like posterior horn and root tears. [75] (10.1016/j.csm.2011.09.005)
• [L4] MAT is a viable and effective surgical option for the painful meniscus-deficient knee, with good survivorship and functional outcomes in the medium to long term. [76] (10.1016/j.arthro.2018.01.010)
• [L4] Open repair of horizontal meniscal tears in young adults leads to good subjective and objective results in the short term, which are maintained in the long-term. [77] (10.1016/j.otsr.2015.09.009)
• [L3] In patients aged 40 years and older, patient-reported outcomes at an average of 5 years postoperatively were satisfactory and similar in patients undergoing meniscal repair and meniscectomy, indicating that age alone should not be a contraindication to meniscal repair. [78] (10.1007/s00167-020-06299-5)
• [L3] This study demonstrates that good long-term outcomes can be obtained in patients up to over 12 years after combined ACL reconstruction and meniscal repair. [79] (10.1007/s00167-011-1501-5)
• [Paper] The role of arthroscopic partial meniscectomy remains controversial; while some surgeons believe it provides dramatic pain relief for specific indications, randomized clinical trials generally do not support its efficacy for degenerative meniscal tears, particularly in patients with osteoarthritis. [80] (10.1097/01.blo.0000533615.20926.05)
• [L3] However, patients with meniscal repair may have slightly worse subjective knee function at both 6- and 12-month follow-up. [81] (10.1007/s00167-017-4793-2)
• [L3] Although the failure rate of meniscus repair may be greater in an unstable knee, meniscal repair is not contraindicated in a knee with a deficient ACL. [82] (10.1007/s00264-004-0616-4)
• [L4] This study demonstrates very good clinical long-term outcomes following meniscal repair in a pediatric population. [83] (10.1177/2325967118s00125)
• [L5] For patients with previously irreparable tears, this represents a cost-effective, low-complexity alternative to meniscectomy or isolated meniscus repair, improving meniscal healing probability while potentially prolonging native knee longevity. [85] (10.1002/atn2.70061)
• [L3] At mean 10-year follow-up, significant clinical improvements and high rates of satisfaction were observed for radial meniscal tear repair. [86] (10.1177/2325967124s00216)
• [L5] Surgeons should strive not to operate in most cases, but to protect, repair or reconstruct, in order to prevent early development of osteoarthritis by restoring the native structure, function, and biomechanics of the meniscus. [87] (10.1302/2058-5241.3.170067)
• [L3] The menisci should be repaired if at all possible, especially in the setting of anterior cruciate ligament reconstruction, for optimal functional outcome and patient satisfaction. [88] (10.1177/03635465020300061501)
• [L4] [91] (10.1016/j.arthro.2011.08.300)
• [L4] [92] (10.1016/j.csm.2013.03.005)
• [L4] The current level 3 and 4 evidence suggests that arthroscopic repair may result in slower progression of radiological deterioration compared with meniscectomy and nonoperative management. [93] (10.1177/03635465211031250)
• [L3] Significant risk factors for false-negative MRI included short time from injury to MRI diagnosis, meniscal tear location within the posterior one-third, and peripheral longitudinal tear pattern. [94] (10.1016/j.arthro.2015.11.046)
• [L5] [96] (10.1177/0363546505279154)
• [L4] Radial tears in the root of the posterior horn of the medial meniscus are common, strongly associated with obesity and older age, and may not be visible in about one-third of preoperative MRI scans. [97] (10.1007/s00167-008-0569-z)
• [L3] Age of 40 years or older is not associated with an increased risk of meniscal repair failure at 5 years, although a shorter time to failure was noted in this age cohort. [100] (10.1016/j.arthro.2018.11.061)
• [L1] Meniscal repair is associated with a lower progression to knee osteoarthritis at approximately six years of followup compared to partial meniscectomy. [101] (10.1007/s00167-023-07600-y)
• [L3] Delay in surgery for >1 year was associated with increased risk of medial meniscal tear. [102] (10.1177/0363546518817749)
• [L2] Meniscal and articular cartilage pathology had a larger impact at 6 years compared to 2 years, with medial meniscal and articular cartilage pathology significantly diminishing activity levels, while lateral meniscal repair or excision improved activity levels. [103] (10.1177/2325967120s00369)
• [L4] A delay from the injury to the surgical procedure was associated with a 3% weekly increased risk of medial meniscal injury for male patients, but not for female patients. [104] (10.2106/jbjs.20.01459)
• [L3] [105] (10.1177/23259671261470917)
• [L2] Clinical examination by an experienced examiner using multiple meniscus tests is sufficient for a diagnosis of a meniscal tear. [106] (10.1007/s00167-011-1636-4)
• [L1] Lateral meniscus tears significantly impact in vivo knee kinematics across all three planes of motion. [108] (10.1177/2325967124s00497)
• [L1] [111] (10.1007/s00167-015-3861-8)
• [L4] These results suggest that non-surgical management is appropriate as first-line therapy in middle-aged patients with symptomatic non-obstructive meniscal tears. [112] (10.1136/bjsports-2019-100567)
• [L5] The meniscus status does have a significant impact on knee kinematics in the ACL-deficient knee. [119] (10.1007/s00264-014-2581-x)
• [L1] [126] (10.1177/0363546516650180)
• [L4] Meniscal tears are commonly seen in each Schatzker classification, with longitudinal tears being the most common pattern. [130] (10.1186/s13018-021-02265-0)
• [L3] Patients with ACL tears treated non-operatively developed secondary meniscal lesions requiring delayed surgical management. [135] (10.1007/s00167-018-5201-2)
• [L5] Such tears do propagate over time regardless of the integrity of the ACL, which might alter knee kinematics and resultant forces in the lateral meniscus as well as bony contact forces at the tibiofemoral joint. [136] (10.1177/2325967119s00238)
• [L2] Factors affecting surgical decision making in meniscal injuries are based more or less only on the patient's clinical symptoms. [142] (10.1007/s001670050164)
• [L4] The ISAKOS classification of meniscal tears is a validated arthroscopic assessment designed to improve the consistency of arthroscopic classification and documentation, thereby improving preoperative planning, standardizing outcome reporting, and enabling an assessment of treatment options across studies. [143] (10.1097/corr.0000000000001948)
• [L4] Our study showed that the CNN model has the potential to be used in diagnosing the presence of meniscal tears and differentiating the types of meniscal tears. [145] (10.1186/s12891-022-05468-6)
• [L5] Arthroscopic partial meniscectomy should not be proposed as a first-line treatment for degenerative meniscus lesions; non-operative treatment should always be started first, with surgery only envisaged after its failure. [146] (10.1007/s00167-017-4458-1)
• [L1] The ISAKOS classification of meniscal tears provides sufficient interobserver reliability for pooling of data from international clinical trials designed to evaluate the outcomes of treatment for meniscal tears. [149] (10.1177/0363546511400533)
• [L1] In patients with knee pain and nonobstructive meniscal tears, physiotherapy was noninferior to arthroscopic partial meniscectomy for knee function over a 24-month period. [150] (10.2106/jbjs.19.00177)
• [L3] Meniscus repair failure risk does not differ between men or women at mid-term follow up. [151] (10.1016/j.arthro.2019.09.030)
• [L5] Meniscal repair has been shown to improve long-term functional scores when compared with meniscectomy. [154] (10.1016/j.arthro.2021.01.003)
• [L1] The benefits of APM in adults with degenerative and nonobstructive meniscal symptoms are limited, with current evidence reporting similarity in outcomes between APM and physical therapy. [159] (10.1007/s00167-022-07040-0)
• [L3] Overall, satisfactory clinical outcomes are achievable at short to midterm follow up with both insideout and all-inside repair of bucket handle meniscal tears in appropriately selected patients. [160] (10.1016/j.arthro.2017.04.105)
• [L5] [161] (10.1016/j.arthro.2019.10.026)
• [L3] Arthroscopic meniscal repair for isolated longitudinal meniscal injuries in stable knees yields favorable functional results, but its effects on the risk of secondary osteoarthritis are not clear. [163] (10.1177/0363546505284236)
• [L5] The authors of the original systematic review maintain that meniscus repair should be adopted as the preferred initial intervention for medial meniscus root tears to prevent knee osteoarthritis, despite the additional evidence presented regarding nonoperative management. [165] (10.1177/0363546518783958)
• [L5] Motion and weight loading of the knee can generate considerable tensile forces in repaired posterior medial meniscal roots. [167] (10.1016/j.arthro.2012.09.004)
• [L5] Initial nonoperative management of degenerative meniscal tears is worth a try. [168] (10.1016/j.arthro.2019.11.128)
• [L4] While this classification provides a detailed description of meniscal lesions, the intraobserver reliability did not reach the optimum values obtained despite having on average a moderate agreement. [179] (10.1177/2325967114s00239)
• [L5] This study shows that an MMPH longitudinal tear in an ACL-deficient knee alters the knee kinematics, particularly the anterior-posterior tibial translation. [180] (10.1177/0363546511416597)
• [L4] MRI is successful in determining the presence or absence of tears in discoid menisci; however, its ability to determine the tear type is questionable. [181] (10.1007/s00167-013-2371-9)
• [L4] Surgeons can reliably classify meniscal pathology and agree on treatment, which is important for multicenter trials. [182] (10.1177/0363546504264586)
• [L4] The utility of MRI to rule out a medial meniscal tear significantly diminished in the young athletic population when >6 months passed between MRI and ACL reconstruction. [185] (10.1177/23259671221141664)
• [L5] Tear propagation significantly increased resultant forces in the lateral meniscus and bony contact forces in intact knees at specific flexion angles. [191] (10.1007/s00167-020-06356-z)
• [L4] The long-term evaluation of the anterior cruciate ligament–reconstructed knees with concurrent successful meniscal repairs demonstrated a low rate of radiographic arthritis. [192] (10.1177/0363546510392014)
• [L3] MRI is not always useful in predicting reparability of symptomatic isolated lateral semilunar meniscus tears, and most of the symptomatic cases with normal MRI were reparable. [194] (10.1007/s00167-002-0280-4)
• [L1] Arthroscopic surgery followed by exercise therapy was not superior to exercise therapy alone for treating non-traumatic, degenerative medial meniscal tears in most middle-aged patients. [195] (10.1007/s00167-012-1960-3)
• [L2] Due to the significantly higher rate of prognostically advantageous meniscal repair, the recommendation for an ACL reconstruction within 6 months after trauma was made to preserve the meniscus and reduce the risk of developing OA. [196] (10.1007/s00167-015-3830-2)
• [L4] It is crucial to differentiate between subtypes of lateral meniscus tears, specifically identifying 'ramp-like' lateral meniscus tears in patients with concomitant anterior cruciate ligament ruptures and associated instability. [199] (10.1016/j.jisako.2024.04.005)
• [L5] The biomechanical consequences of a lateral meniscus root tear depend on the state of the meniscofemoral ligament. [200] (10.1007/s00402-013-1716-7)
• [L4] Given the paucity of randomized controlled studies, no definite conclusions can be made regarding the difference in clinical outcomes of various all-inside meniscal repair devices. [201] (10.1097/blo.0b013e31802ff806)
• [L3] Meniscus repair in the revision setting is a successful treatment choice when appropriate. [202] (10.1177/2325967117s00239)
• [L3] In a population of patients aged 40 and older with surgically treated meniscal tears, meniscal repair was associated with higher overall reoperation rates and shorter survival times compared to meniscectomy. [203] (10.1016/j.arthro.2024.09.022)
• [L5] The integrity of the posterior root of the medial meniscus plays an important role in maintaining normal tibial-femoral joint contact mechanics. [211] (10.1186/s12891-022-06069-z)
• [L2] Discriminating use of MRI offers major advantages in selected patients with unclarified meniscus lesions. [215] (10.1007/bf00449992)
• [L3] Confusion between meniscal fraying and small tears is a major source of discrepancy between MRI and surgical findings. [218] (10.1007/s00402-007-0318-7)
• [L3] Physicians should suspect that an inverted-type discoid lateral meniscus tear is present during diagnosis and focus on the posterior horn to find the inverted sign on the MRI sagittal plane. [219] (10.1186/s12891-019-2618-9)
• [L3] Surgeons should strongly encourage adherence to these conservative modalities in patients awaiting operative reconstruction to reduce the risk of secondary meniscal pathology. [220] (10.1177/23259671241309862)
• [L3] Magnetic resonance imaging is not an effective or efficient predictor of reparability of meniscal tears with the current arthroscopic criteria. [223] (10.1177/0363546510387507)
• [L3] Surgeons should counsel patients preoperatively about increased possibility of undiagnosed medial meniscus tears being found at the time of ACLR if greater than 6 months have passed from MRI to surgery. [226] (10.1177/2325967121s00528)
• [L2] Based on the reported MRI incidence of false positives with the medial meniscus and false negatives with the lateral meniscus and based on assumed standards of care, more costly care is provided when using MRI compared with NA. [231] (10.1016/j.arthro.2018.09.030)
• [L4] Medial meniscus posterior root tear may occur in severe medial instability from trauma and is often missed on MRI diagnosis. [233] (10.1007/s00167-014-3274-0)
• [L4] Considering the high number of false negatives of meniscal tears in preoperative MRI, high suspicion for specific tears should be used taking into account also the patient's remaining growth. [234] (10.1002/ksa.12729)
• [L5] Compositional sequences for MRI can allow for an evaluation of the biochemical properties of cartilage, meniscus, and ligament that offer further insight into pathology that may not be apparent on conventional clinical imaging. [235] (10.1002/jor.24462)
• [L3] The accuracy of MRI in diagnosing discoid lateral meniscus is significantly lower in the presence of radial or longitudinal tears. [239] (10.1007/s00167-017-4704-6)
• [L3] For the medial meniscus, where horizontal and complex tears were more prevalent, 3-Tesla MRI shows a higher accuracy than for the lateral meniscus. [240] (10.1007/s00402-007-0485-6)
• [L4] MRI criteria confirming meniscal healing after traumatic meniscal repair at 1 year were identified: a change in the intrameniscal signal becoming nonfluid and moderate in intensity; a reduction in tear diastasis to <1.5 mm; and a change in the signal morphology of the repaired meniscus. [241] (10.1177/03635465231207838)
• [L4] [242] (10.1177/0363546517743734)
• [L3] [243] (10.1002/ksa.70144)
• [L2] [247] (10.1007/s00167-020-05847-3)
• [L4] Risk factors for failure included chronicity of injury, tear location more than 3 mm from the meniscosynovial junction, and medial meniscus side. [251] (10.1007/s00167-004-0527-3)
• [L3] Time from ACL injury to reconstruction of 3 months was strongly associated with medial meniscal injuries and irreparable medial meniscal tears at primary ACLR. [253] (10.1177/2325967121989036)
• [L3] In female patients who experienced an ACL injury, a delay in surgery greater than 12 months is associated with a gradual increase in the risk of nonrepairable medial meniscal tear; this risk becomes statistically significant after 24 months. [254] (10.1016/j.arthro.2022.10.014)
• [L3] Delaying ACLR to 8 to 12 weeks after injury may optimize the potential for spontaneous healing in lateral meniscus injuries, particularly posterior horn longitudinal and radial tears, potentially increasing meniscal healing rates by 1.5 to 2.5 times compared with early intervention. [255] (10.1177/23259671251402990)

See Also

• Meniscal repair
• ACL reconstruction
• Partial meniscectomy
• Meniscal root tear
• Knee osteoarthritis

References

[1] Miller S Review Of Orthopaedics. MENISCAL INJURIES.

[2] Miller S Review Of Orthopaedics. SECTION 16 PATELLAR TRACKING IN TOTAL KNEE ARTHROPLASTY > MENISCAL INJURIES.

[3] Orthopaedic Knowledge Update Sports Medicine 6. Meniscal Injuries > Management.

[4] Aaos Comprehensive Orthopaedic Review 3. Meniscal Injuries > V. Treatment.

[5] Surgical Techniques and Outcomes of Repairing Meniscal Radial Tears: A Systematic Review. Arthroscopy. 2016. DOI: 10.1016/j.arthro.2016.03.029

[6] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Knee Arthroscopy and Preservation, Knee Reconstruction > Knee Preservation > Meniscal Preservation.

[7] The Long-term Consequence of Anterior Cruciate Ligament and Meniscus Injuries. The American Journal of Sports Medicine. 2007. DOI: 10.1177/0363546507307396

[8] Editorial Commentary: Women and Men Fare Equally Well After Meniscal Repair. Arthroscopy. 2020. DOI: 10.1016/j.arthro.2019.12.017

[9] Meniscus Repair Part 2: Technical Aspects, Biologic Augmentation, Rehabilitation, and Outcomes. Journal of the American Academy of Orthopaedic Surgeons. 2022. DOI: 10.5435/jaaos-d-21-01153

[10] Campbell S Operative Orthopaedics 4 Volume Set. ARTHROSCOPIC EXAMINATION AND DEBRIDEMENT OF THE ANKLE JOINT > ARTHROSCOPIC SURGERY OF THE MENISCUS > CLASSIFICATION OF MENISCAL TEARS.

[11] Risk Factors for Meniscectomy After Meniscal Repair. The American Journal of Sports Medicine. 2013. DOI: 10.1177/0363546513503444

[12] Meniscus Root Avulsion. Clinics in Sports Medicine. 2012. DOI: 10.1016/j.csm.2011.08.013

[13] Meniscal allograft transplantation: a review of indications, techniques, and outcomes. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-06058-6

[14] Meniscal allograft transplantation in The Netherlands: long-term survival, patient-reported outcomes, and their association with preoperative complaints and interventions. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-06276-y

[16] Campbell S Operative Orthopaedics 4 Volume Set. CLASSIFICATION OF MENISCAL TEARS.

[17] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Plate 35.2 Scapulocostal Stabilization for Scapular Winging (Ketenjian Technique) > Meniscal Injuries > Treatment.

[19] Meniscal Root Tears. The American Journal of Sports Medicine. 2014. DOI: 10.1177/0363546514524162

[20] Magnetic Resonance Imaging Is an Effective First‐Line Noninvasive Tool for Meniscal Tear Detection: A Retrospective Comparative Analysis With Knee Arthroscopy. Arthroscopy, Sports Medicine, and Rehabilitation. 2024. DOI: 10.1016/j.asmr.2024.101065

[26] Aaos Comprehensive Orthopaedic Review 3. Meniscal Injuries > III. Evaluation.

[28] The role of meniscal tissue in joint protection in early osteoarthritis. Knee Surgery, Sports Traumatology, Arthroscopy. 2016. DOI: 10.1007/s00167-016-4069-2

[29] The Clinical Significance of Anterior Horn Meniscal Tears Diagnosed on Magnetic Resonance Images ^{. The American Journal of Sports Medicine. 2002. DOI: 10.1177/03635465020300020701}

[30] Higher survivorship following meniscal allograft transplantation in less worn knees justifies earlier referral for symptomatic patients: experience from 240 patients. Knee Surgery, Sports Traumatology, Arthroscopy. 2019. DOI: 10.1007/s00167-019-05459-6

[31] Surgical Treatment of Isolated Meniscal Tears in Competitive Male Wrestlers: Reoperations, Outcomes, and Return to Sport. Orthopaedic Journal of Sports Medicine. 2021. DOI: 10.1177/2325967120969220

[32] Meniscal Allograft Survivorship and Outcomes 20 Years After Implantation. Arthroscopy. 2020. DOI: 10.1016/j.arthro.2020.04.029

[34] New England Journal of Medicine Article Evaluating the Usefulness of Meniscectomy Is Flawed. Arthroscopy. 2014. DOI: 10.1016/j.arthro.2014.03.016

[35] Comparative Outcomes of Radial and Bucket-Handle Meniscal Tear Repair: A Propensity-Matched Analysis. The American Journal of Sports Medicine. 2018. DOI: 10.1177/0363546518786035

[36] Editorial Commentary: Complications After Meniscal Surgery Are Rare and Generally Associated With Medical Comorbidity. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2023.12.017

[39] Orthopaedic Knowledge Update. Meniscal Tears in Children and Adolescents > Traumatic Meniscal Tears > Management.

[41] Meniscal Injury: II. Management. Journal of the American Academy of Orthopaedic Surgeons. 2002. DOI: 10.5435/00124635-200205000-00004

[42] Clinical and arthroscopic features of meniscal tears and a search for the role of infection in histologically confirmed meniscal mucoid degeneration. Knee Surgery, Sports Traumatology, Arthroscopy. 2003. DOI: 10.1007/s00167-003-0412-5

[43] As Goes the Meniscus Goes the Knee. Clinics in Sports Medicine. 2020. DOI: 10.1016/j.csm.2019.08.001

[45] Association of MRI findings and expert diagnosis of symptomatic meniscal tear among middle-aged and older adults with knee pain. BMC Musculoskeletal Disorders. 2016. DOI: 10.1186/s12891-016-1010-2

[47] Clinical presentation, MRI and clinical outcome scores do not accurately predict an important meniscal tear in a symptomatic discoid meniscus. Knee Surgery, Sports Traumatology, Arthroscopy. 2021. DOI: 10.1007/s00167-020-06375-w

[48] A correlation of time with meniscal tears in anterior cruciate ligament deficiency: stratifying the risk of surgical delay. Knee Surgery, Sports Traumatology, Arthroscopy. 2008. DOI: 10.1007/s00167-008-0622-y

[49] One‐Third of Meniscal Tears Are Repairable: An Epidemiological Study Evaluating Meniscal Tear Patterns in Stable and Unstable Knees. Arthroscopy. 2019. DOI: 10.1016/j.arthro.2018.08.051

[52] Magnetic Resonance Imaging in Acute Traumatic and Chronic Meniscal Tears of the Knee. The American Journal of Sports Medicine. 2009. DOI: 10.1177/0363546508329543

[53] Accuracy measures of 1.5-tesla MRI for the diagnosis of ACL, meniscus and articular knee cartilage damage and characteristics of false negative lesions: a level III prognostic study. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04011-3

[55] Magnetic resonance imaging can increase the diagnostic accuracy in symptomatic meniscal repair patients. Knee Surgery, Sports Traumatology, Arthroscopy. 2019. DOI: 10.1007/s00167-019-05523-1

[57] Editorial Commentary: Book? … Book Report? … or Just a New Chapter in an Ongoing Story?: Knee Partial Meniscectomy Has Limited Benefit for “Nonobstructive” Meniscal Tears, but We Need to Know if Patients Have Osteoarthritis. Arthroscopy. 2016. DOI: 10.1016/j.arthro.2016.07.013

[59] Meniscus Tear Morphology and Patient Demographics as Predictors of Treatment for Meniscal Tears: A Natural Language Processing Study. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671251397648

[60] Anterior medial meniscus detachment and anterior cruciate ligament tear. Knee Surgery, Sports Traumatology, Arthroscopy. 2006. DOI: 10.1007/s00167-006-0255-y

[62] Campbell S Operative Orthopaedics 4 Volume Set. ARTHROSCOPIC EXAMINATION AND DEBRIDEMENT OF THE ANKLE JOINT > ARTHROSCOPIC SURGERY OF THE MENISCUS > TYPES OF MENISCAL EXCISIONS.

[66] Meniscus Scaffolds for Partial Meniscus Defects. Clinics in Sports Medicine. 2020. DOI: 10.1016/j.csm.2019.08.011

[67] MR‐arthrography assessment after repair of chronic meniscal tears. Knee Surgery, Sports Traumatology, Arthroscopy. 2013. DOI: 10.1007/s00167-013-2552-6

[69] Editorial Commentary: Older Age Is Not a Contraindication to Meniscal Repair. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2024.11.058

[71] Nineteen percent of meniscus repairs are being revised and failures frequently occur after the second postoperative year: a systematic review and meta‐analysis with a minimum follow‐up of 5 years. Knee Surgery, Sports Traumatology, Arthroscopy. 2021. DOI: 10.1007/s00167-021-06770-x

[73] Open Meniscal Repair: Clinical and Magnetic Resonance Imaging Findings After Twelve Years. The American Journal of Sports Medicine. 1999. DOI: 10.1177/03635465990270011001

[75] Meniscal Repair. Clinics in Sports Medicine. 2012. DOI: 10.1016/j.csm.2011.09.005

[76] Meniscal Allograft Transplantation: The Effect of Cartilage Status on Survivorship and Clinical Outcome. Arthroscopy. 2018. DOI: 10.1016/j.arthro.2018.01.010

[77] Analysis of short and long-term results of horizontal meniscal tears in young adults. Orthopaedics & Traumatology: Surgery & Research. 2015. DOI: 10.1016/j.otsr.2015.09.009

[78] Patient‐reported outcomes of meniscal repair and meniscectomy in patients 40 years of age and older show similar good results. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-06299-5

[79] Meniscal repair in anterior cruciate ligament reconstruction: a long‐term outcome study. Knee Surgery, Sports Traumatology, Arthroscopy. 2011. DOI: 10.1007/s00167-011-1501-5

[80] Clinical Faceoff: The Role of Arthroscopic Partial Meniscectomy in the Treatment of Meniscal Tears. Clinical Orthopaedics & Related Research. 2018. DOI: 10.1097/01.blo.0000533615.20926.05

[81] Meniscal repair results in inferior short-term outcomes compared with meniscal resection: a cohort study of 6398 patients with primary anterior cruciate ligament reconstruction. Knee Surgery, Sports Traumatology, Arthroscopy. 2017. DOI: 10.1007/s00167-017-4793-2

[82] Arthroscopic meniscus repair in the ACL-deficient knee. International Orthopaedics. 2005. DOI: 10.1007/s00264-004-0616-4

[83] Long-term Follow Up of Arthroscopically Repaired Meniscal Tears in a Pediatric Population. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118s00125

[85] Arthroscopic Repair of Radial Meniscal Tear Using Fibrin Clot Augmentation and “Hashtag” Style Inside‐Out Technique. Arthroscopy Techniques. 2026. DOI: 10.1002/atn2.70061

[86] Poster 247: Comparative Outcomes of Radial and Bucket-Handle Meniscal Tear Repair at Mean 10 Years: A Propensity-Matched Analysis. Orthopaedic Journal of Sports Medicine. 2024. DOI: 10.1177/2325967124s00216

[87] Modern treatment of meniscal tears. EFORT Open Reviews. 2018. DOI: 10.1302/2058-5241.3.170067

[88] Effects of Meniscal and Articular Surface Status on Knee Stability, Function, and Symptoms after Anterior Cruciate Ligament Reconstruction. The American Journal of Sports Medicine. 2002. DOI: 10.1177/03635465020300061501

[91] Meniscal Morphologic Changes on Magnetic Resonance Imaging Are Associated With Symptomatic Discoid Lateral Meniscal Tear in Children. Arthroscopy. 2011. DOI: 10.1016/j.arthro.2011.08.300

[92] Magnetic Resonance Imaging and Arthroscopic Appearance of the Menisci of the Knee. Clinics in Sports Medicine. 2013. DOI: 10.1016/j.csm.2013.03.005

[93] Are Outcomes of Acute Meniscus Root Tear Repair Better Than Debridement or Nonoperative Management? A Systematic Review. The American Journal of Sports Medicine. 2021. DOI: 10.1177/03635465211031250

[94] Risk Factors of False‐Negative Magnetic Resonance Imaging Diagnosis for Meniscal Tear Associated With Anterior Cruciate Ligament Tear. Arthroscopy. 2016. DOI: 10.1016/j.arthro.2015.11.046

[95] Orthopaedic Knowledge Update Sports Medicine 6. Meniscal Injuries > Management > Root Tears.

[96] Taking the Long View. The American Journal of Sports Medicine. 2005. DOI: 10.1177/0363546505279154

[97] Radial tears in the root of the posterior horn of the medial meniscus. Knee Surgery, Sports Traumatology, Arthroscopy. 2008. DOI: 10.1007/s00167-008-0569-z

[100] Age of 40 Years or Older Does Not Affect Meniscal Repair Failure Risk at 5 Years. Arthroscopy. 2019. DOI: 10.1016/j.arthro.2018.11.061

[101] Meniscectomy is associated with a higher rate of osteoarthritis compared to meniscal repair following acute tears: a meta‐analysis. Knee Surgery, Sports Traumatology, Arthroscopy. 2023. DOI: 10.1007/s00167-023-07600-y

[102] Delayed ACL Reconstruction in Patients ≥40 Years of Age Is Associated With Increased Risk of Medial Meniscal Injury at 1 Year. The American Journal of Sports Medicine. 2019. DOI: 10.1177/0363546518817749

[103] Meniscal and Articular Cartilage Predictors of Outcome following Revision ACL Reconstruction: A 6-Year Follow-up Study. Orthopaedic Journal of Sports Medicine. 2020. DOI: 10.1177/2325967120s00369

[104] ACL Reconstruction Delay in Pediatric and Adolescent Patients Is Associated with a Progressive Increased Risk of Medial Meniscal Tears. Journal of Bone and Joint Surgery. 2021. DOI: 10.2106/jbjs.20.01459

[105] Influence of Concomitant Articular Cartilage Injury on the Diagnostic Performance of Physical Examination Tests for Meniscal Tears. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671261470917

[106] History, clinical findings, magnetic resonance imaging, and arthroscopic correlation in meniscal lesions. Knee Surgery, Sports Traumatology, Arthroscopy. 2011. DOI: 10.1007/s00167-011-1636-4

[108] Cross-sectional Effects of Isolated Meniscal Tears on In Vivo Biomechanics of the Knee: A Systematic Review of Motion Analysis Studies. Orthopaedic Journal of Sports Medicine. 2024. DOI: 10.1177/2325967124s00497

[111] A systematic review and meta-analysis of the diagnostic accuracy of MRI for suspected ACL and meniscal tears of the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2015. DOI: 10.1007/s00167-015-3861-8

[112] Can even experienced orthopaedic surgeons predict who will benefit from surgery when patients present with degenerative meniscal tears? A survey of 194 orthopaedic surgeons who made 3880 predictions. British Journal of Sports Medicine. 2019. DOI: 10.1136/bjsports-2019-100567

[119] The influence of the medial meniscus in different conditions on anterior tibial translation in the anterior cruciate deficient knee. International Orthopaedics. 2014. DOI: 10.1007/s00264-014-2581-x

[126] The Urgent Need for Evidence in Arthroscopic Meniscal Surgery: A Systematic Review of the Evidence for Operative Management of Meniscal Tears. The American Journal of Sports Medicine. 2016. DOI: 10.1177/0363546516650180

[127] Orthopaedic Knowledge Update Sports Medicine 6. Meniscal Injuries > Diagnosis.

[128] Orthopaedic Knowledge Update Sports Medicine 6. Meniscal Injuries > Anatomy.

[130] Arthroscopically assisted evaluation of frequency and patterns of meniscal tears in operative tibial plateau fractures: a retrospective study. Journal of Orthopaedic Surgery and Research. 2021. DOI: 10.1186/s13018-021-02265-0

[135] Delayed reconstruction and high BMI z score increase the risk of meniscal tear in paediatric and adolescent anterior cruciate ligament injury. Knee Surgery, Sports Traumatology, Arthroscopy. 2018. DOI: 10.1007/s00167-018-5201-2

[136] Small Lateral Meniscus Tears Propagate and are Detrimental to Knee Kinematics and Contact Forces. Orthopaedic Journal of Sports Medicine. 2019. DOI: 10.1177/2325967119s00238

[142] The role of magnetic resonance imaging in routine decision making for meniscal surgery. Knee Surgery, Sports Traumatology, Arthroscopy. 1999. DOI: 10.1007/s001670050164

[143] Classifications in Brief: The International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine Classification of Meniscal Tears. Clinical Orthopaedics & Related Research. 2021. DOI: 10.1097/corr.0000000000001948

[145] Development of convolutional neural network model for diagnosing meniscus tear using magnetic resonance image. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-05468-6

[146] The difficult balance between scientific evidence and clinical practice: the 2016 ESSKA meniscus consensus on the surgical management of degenerative meniscus lesions. Knee Surgery, Sports Traumatology, Arthroscopy. 2017. DOI: 10.1007/s00167-017-4458-1

[149] Interobserver Reliability of the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) Classification of Meniscal Tears. The American Journal of Sports Medicine. 2011. DOI: 10.1177/0363546511400533

[150] In Patients with Nonobstructive Meniscal Tears, Physiotherapy Was Noninferior to Arthroscopic Partial Meniscectomy for Knee Function Over a 24-Month Period. Journal of Bone and Joint Surgery. 2019. DOI: 10.2106/jbjs.19.00177

[151] Subjective Knee Function and Risk of Failure Are Equivalent for Men and Women at 5 Years After Meniscus Repair. Arthroscopy. 2020. DOI: 10.1016/j.arthro.2019.09.030

[154] Meniscal Repair Techniques for Middle- and Posterior-Third Tears. Arthroscopy: The Journal of Arthroscopic & Related Surgery. 2021. DOI: 10.1016/j.arthro.2021.01.003

[156] Aaos Comprehensive Orthopaedic Review 3. Meniscal Injuries > II. Pathoanatomy.

[159] No evidence in support of arthroscopic partial meniscectomy in adults with degenerative and nonobstructive meniscal symptoms: a level I evidence‐based systematic review. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-07040-0

[160] Comparative Outcomes of All‐Inside and Inside‐Out Repairs of Bucket‐Handle Meniscal Tears. Arthroscopy. 2017. DOI: 10.1016/j.arthro.2017.04.105

[161] Editorial Commentary: Degenerative Meniscal Tear: Sojourn to the Oracle. Arthroscopy. 2020. DOI: 10.1016/j.arthro.2019.10.026

[163] Midterm and Long-term Results after Arthroscopic Suture Repair of Isolated, Longitudinal, Vertical Meniscal Tears in Stable Knees. The American Journal of Sports Medicine. 2006. DOI: 10.1177/0363546505284236

[165] Should Surgical Repair Be Recommended Over Nonoperative Management for Medial Meniscus Root Tears? Letter to the Editor. The American Journal of Sports Medicine. 2018. DOI: 10.1177/0363546518783958

[167] Tensile Forces on Repaired Medial Meniscal Root Tears. Arthroscopy. 2013. DOI: 10.1016/j.arthro.2012.09.004

[168] Nonoperative Management of Degenerative Meniscus Tears Is Worth a Try. Arthroscopy. 2019. DOI: 10.1016/j.arthro.2019.11.128

[179] ISAKOS Classification of Meniscal Tears. Intra and Interobserver Reliability.. Orthopaedic Journal of Sports Medicine. 2014. DOI: 10.1177/2325967114s00239

[180] Longitudinal Tear of the Medial Meniscus Posterior Horn in the Anterior Cruciate Ligament–Deficient Knee Significantly Influences Anterior Stability. The American Journal of Sports Medicine. 2011. DOI: 10.1177/0363546511416597

[181] Comparison of magnetic resonance imaging findings with arthroscopic findings in discoid meniscus. Knee Surgery, Sports Traumatology, Arthroscopy. 2013. DOI: 10.1007/s00167-013-2371-9

[182] Multirater Agreement of Arthroscopic Meniscal Lesions. The American Journal of Sports Medicine. 2004. DOI: 10.1177/0363546504264586

[185] Effect of Increased Time to Surgery on the Ability of MRI to Rule Out Medial Meniscal Tears in Young Athletes With ACL Injury. Orthopaedic Journal of Sports Medicine. 2023. DOI: 10.1177/23259671221141664

[191] Small lateral meniscus tears propagate over time in ACL intact and deficient knees. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-06356-z

[192] Greater Than 10-Year Results of Red-White Longitudinal Meniscal Repairs in Patients 20 Years of Age or Younger. The American Journal of Sports Medicine. 2011. DOI: 10.1177/0363546510392014

[194] Prediction of reparability of isolated semilunar lateral meniscus tears by magnetic resonance imaging. Knee Surgery, Sports Traumatology, Arthroscopy. 2002. DOI: 10.1007/s00167-002-0280-4

[195] Is arthroscopic surgery beneficial in treating non‐traumatic, degenerative medial meniscal tears? A five year follow‐up. Knee Surgery, Sports Traumatology, Arthroscopy. 2012. DOI: 10.1007/s00167-012-1960-3

[196] Timing of anterior cruciate ligament reconstruction within the first year after trauma and its influence on treatment of cartilage and meniscus pathology. Knee Surgery, Sports Traumatology, Arthroscopy. 2015. DOI: 10.1007/s00167-015-3830-2

[199] Ramp-like lateral meniscus tear. Description of an infrequent lesion. Journal of ISAKOS. 2024. DOI: 10.1016/j.jisako.2024.04.005

[200] Biomechanical consequences of a posterior root tear of the lateral meniscus: stabilizing effect of the meniscofemoral ligament. Archives of Orthopaedic and Trauma Surgery. 2013. DOI: 10.1007/s00402-013-1716-7

[201] All-inside Meniscus Repair. Clinical Orthopaedics and Related Research. 2007. DOI: 10.1097/blo.0b013e31802ff806

[202] Meniscal Repair Outcomes in Revision ACL Reconstructions. Orthopaedic Journal of Sports Medicine. 2017. DOI: 10.1177/2325967117s00239

[203] Reoperation Rates of Meniscal Repair Are Associated With a Higher Reoperation Rate Than Meniscectomy in Patients Aged 40 and Older. Arthroscopy. 2024. DOI: 10.1016/j.arthro.2024.09.022

[211] Biomechanical assessment of disease outcome in surgical interventions for medial meniscal posterior root tears: a finite element analysis. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-06069-z

[215] Intrasubstance meniscal tears. Archives of Orthopaedic and Trauma Surgery. 1993. DOI: 10.1007/bf00449992

[218] MR diagnosis of meniscal tears of the knee: analysis of error patterns. Archives of Orthopaedic and Trauma Surgery. 2007. DOI: 10.1007/s00402-007-0318-7

[219] The characteristic findings of an inverted-type discoid lateral meniscus tear: a hidden tear pattern. BMC Musculoskeletal Disorders. 2019. DOI: 10.1186/s12891-019-2618-9

[220] The Role of Crutches and Bracing in Preventing Secondary Meniscal Tears After Anterior Cruciate Ligament Injury in Pediatric Patients. Orthopaedic Journal of Sports Medicine. 2025. DOI: 10.1177/23259671241309862

[223] Can the Reparability of Meniscal Tears Be Predicted With Magnetic Resonance Imaging?. The American Journal of Sports Medicine. 2010. DOI: 10.1177/0363546510387507

[226] Negative Predictive Value of Mri-Detected Medial Meniscus Tears is Reduced in Young Athletes with Chronic ACL Injury. Orthopaedic Journal of Sports Medicine. 2022. DOI: 10.1177/2325967121s00528

[227] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Plate 35.2 Scapulocostal Stabilization for Scapular Winging (Ketenjian Technique) > Meniscal Injuries > Clinical Features.

[231] Cost‐Effectiveness Analysis of Needle Arthroscopy Versus Magnetic Resonance Imaging in the Diagnosis and Treatment of Meniscal Tears of the Knee. Arthroscopy. 2019. DOI: 10.1016/j.arthro.2018.09.030

[233] Traumatic posterior root tear of the medial meniscus in patients with severe medial instability of the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2014. DOI: 10.1007/s00167-014-3274-0

[234] Incidence of meniscal tears in skeletally immature patients with anterior cruciate ligament (ACL) rupture: Medial tears are more common in patients closer to skeletal maturity while lateral tears in those with more remaining growth. Knee Surgery, Sports Traumatology, Arthroscopy. 2025. DOI: 10.1002/ksa.12729

[235] Clinical Utility of Advanced Imaging of the Knee. Journal of Orthopaedic Research. 2019. DOI: 10.1002/jor.24462

[239] Discoid lateral meniscus can be overlooked by magnetic resonance imaging in patients with meniscal tears. Knee Surgery, Sports Traumatology, Arthroscopy. 2017. DOI: 10.1007/s00167-017-4704-6

[240] Diagnostics of degenerative meniscal tears at 3-Tesla MRI compared to arthroscopy as reference standard. Archives of Orthopaedic and Trauma Surgery. 2007. DOI: 10.1007/s00402-007-0485-6

[241] MRI Criteria for Healing at 1 Year After Repair of a Traumatic Meniscal Tear. The American Journal of Sports Medicine. 2023. DOI: 10.1177/03635465231207838

[242] The Role of Meniscal Tears in Spontaneous Osteonecrosis of the Knee: A Systematic Review of Suspected Etiology and a Call to Revisit Nomenclature. The American Journal of Sports Medicine. 2017. DOI: 10.1177/0363546517743734

[243] One‐third of meniscal repairs undergo reoperation within five years: Incidence and predictors in a retrospective study of 2390 cases. Knee Surgery, Sports Traumatology, Arthroscopy. 2025. DOI: 10.1002/ksa.70144

[247] Management of traumatic meniscus tears: the 2019 ESSKA meniscus consensus. Knee Surgery, Sports Traumatology, Arthroscopy. 2020. DOI: 10.1007/s00167-020-05847-3

[251] Arthroscopic meniscal repair with an absorbable screw: results and surgical technique. Knee Surgery, Sports Traumatology, Arthroscopy. 2004. DOI: 10.1007/s00167-004-0527-3

[253] Risk Factors Related to the Presence of Meniscal Injury and Irreparable Meniscal Tear at Primary Anterior Cruciate Ligament Reconstruction. Orthopaedic Journal of Sports Medicine. 2021. DOI: 10.1177/2325967121989036

[254] Increased Time to Surgery After Anterior Cruciate Ligament Tear in Female Patients Results in Greater Risk of Medial Meniscus Tear: A Study of 489 Female Patients. Arthroscopy. 2022. DOI: 10.1016/j.arthro.2022.10.014

[255] Spontaneous Healing of Meniscal Tears With ACL Injuries and Its Impact on Timing of ACL Surgery. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671251402990