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Posterolateral corner injury

65 citationsUpdated Sep 2026

Overview

Prompt recognition of posterolateral corner (PLC) injuries is critical, as missed diagnoses increase failure rates for cruciate ligament reconstructions and lead to chronic disability [1]. Injuries to the posterolateral corner, whether isolated or combined, are best treated by reconstructing the PLC along with any coexisting cruciate ligament injury [5]. For patients with combined anterior cruciate ligament (ACL) and PLC injuries, full reconstruction appears to be the optimal strategy [2]. The authors now favor reconstruction over repair in the majority of patients sustaining PLC tears after high-energy injuries [3], noting that repair may yield higher revision rates compared with reconstruction [7]. Anatomic PLC reconstruction with autografts provides superior stability compared to non-anatomic reconstruction in the setting of combined grade 3 PLC injuries and single-bundle posterior cruciate ligament (PCL) reconstruction [8, 9]. Furthermore, a combined PCL and PLC reconstruction can restore intact knee kinematics at time zero [4].

In the context of multi-ligament knee injuries (MLKI), outcomes may be negatively influenced by bicruciate ligament, meniscal, and cartilage injuries, as well as treatment characteristics such as the need for PLC or bicruciate ligament reconstruction, use of allografts, or meniscal repair [55]. Injured posterolateral structures should be repaired before fixation of ACL grafts [16]. Recent studies of rotational stability suggest no advantage of double-bundle reconstruction in the setting of concomitant PLC repair, but indicate a possible advantage in the setting of subtle PLC injury [10]. Both surgical techniques for anatomical PLC reconstruction have shown good results in static laxity tests [11], and no effect of popliteal tendon reconstruction was found on stability and clinical results in anatomic PLC reconstruction [24]. While numerous surgical techniques for repair and reconstruction have been described, long-term functional results have been only moderately successful [14].

The technique described could be clinically relevant for future arthroscopic PLC reconstructions [6]. Injuries to the posteromedial corner are common in traumatic knee dislocations [12], with the posterior oblique ligament (POL) serving as the predominant structure; surgical reconstruction is considered the gold standard treatment for POL injury [15]. Most isolated medial collateral ligament injuries are treated nonsurgically, whereas concomitant damage to the ACL or PCL is a common indication for surgical management of high-grade injuries [19]. Extra-articular anterolateral procedures have undergone a renaissance in combination with ACL reconstruction in selected cases, though there is a clear need for more high-level clinical evidence to support their routine use [57]. This study presents mid-term outcomes of one of the largest series of consecutive multi-ligament knee injuries reported to date [20].

Anatomy & Pathophysiology

Anatomical Structures

The posterolateral corner (PLC) of the knee comprises the fibular collateral ligament (FCL), the iliotibial band, the popliteofibular ligament, the biceps femoris, and the popliteus tendon [82]. The lateral collateral ligament (LCL) extends from the lateral femoral condyle to the head of the fibula, serving as the primary stabilizer against varus stress and a component of the posterolateral complex that resists external rotation [37]. The popliteofibular ligament, present in 90% of knees, connects the popliteus tendon to the styloid on the posterior fibular head [37]. The popliteus tendon originates on the posterocentral tibia and inserts anterior and distal to the LCL on the lateral femoral epicondyle, traversing an intra-articular course through the popliteal hiatus [76].

The lateral meniscus is larger than the medial meniscus and bears a greater share of lateral compartment pressure than the medial meniscus does for the medial compartment [37]. While the lateral meniscus attaches to the anterior and posterior capsule, a region posterolaterally lacks firm attachment [37]. Osseous morphology influences these structures; the lateral tibial plateau is smaller and more circular than the medial plateau, concave in the frontal plane and convex in the sagittal plane [63]. Conversely, the lateral femoral condyle projects farther anteriorly and is wider in the medial-lateral direction than the medial femoral condyle [63].

Vascular & Neural Anatomy

The common peroneal nerve travels along the posterior edge of the biceps femoris and continues distally around the fibular neck [82]. The popliteus artery passes through the adductor hiatus, where it is relatively immobile, and distally through the fibrous arch deep to the soleus muscle [82].

Biomechanical Function

The PLC resists posterior translation, external rotation, and varus angulation of the tibia [82]. Specific ligaments contribute distinct biomechanical functions: * LCL: Primarily resists varus tibial translation and secondarily resists tibial external rotation, particularly at 30 degrees of knee flexion [64]. * Popliteus tendon: Primarily resists tibial external rotation, especially in knee flexion, and secondarily resists varus tibial translation [64]. * Popliteofibular ligament: Primarily resists tibial external rotation, especially in knee flexion, and secondarily resists posterior tibial displacement [64]. * Oblique popliteal ligament: Primarily resists knee hyperextension and secondarily resists varus tibial translation [64].

Marked ligament laxity of the knee, particularly of the posterolateral corner, can occur even when the iliotibial band is intact [18]. Consequently, injury to the biceps femoris muscle is often not appreciated initially because the intact iliotibial band prevents noticeable hemorrhage [18].

Pathophysiology and Injury Patterns

Progressive damage to translational and rotational knee soft-tissue restraints occurs with increasing knee hyperextension [25]. Missed posterolateral corner injuries increase failure rates for cruciate ligament reconstructions and lead to chronic disability [1]. Posterolateral rotatory instability is rarely diagnosed in the acute stage and is often not recognized until it has become a chronic problem [18].

In the context of multiligament injuries, the pathoanatomy of posterolateral corner ligamentous disruption is predictive of peroneal nerve injury [33]. A graft that restores knee kinematics for an isolated posterior cruciate ligament deficiency is rendered ineffective and may be overloaded if the posterolateral structures are deficient [100]. Isolated PCL reconstruction, whether single-bundle or double-bundle, could not restore normal knee kinematics in the PCL/PLC-deficient knee [123]. Biomechanical studies demonstrate significantly higher graft force during varus loading at 0 and 30 degrees of knee flexion after transection of the LCL compared with intact posterolateral structures [41]. Therefore, in knees with grade III posterolateral injuries and evidence of varus or coupled posterior-external rotation instability, repair or reconstruction of the posterolateral structures should be performed at the time of PCL reconstruction to decrease the chance of later graft failure [41].

The common peroneal nerve is at risk of injury during PLC surgery, particularly before deep dissection and while drilling through the fibula head for graft reconstruction [23].

Classification

Instabilities resulting from tears of the lateral-compartment ligaments are less common than medial-compartment instabilities but are more easily overlooked and more disabling [47]. The Schenck classification serves as a useful communication, planning, and prognostic tool for evaluating potential associated neurovascular injuries in knee dislocations [138]. The current MLKI classification system is more than 20 years old and represents an improvement over previous classification systems [132]. A proposed classification system for multiple ligament knee injuries includes each specific structure injured, modifiers for fractures, extensor mechanism injuries, nerve injuries, or vascular injuries, specific anatomic location of structures injured meniscus and articular cartilage injuries, and injury timing (acute, chronic) [132].

The Modified Dorsolateral Instability Classification defines Type 1 as isolated posterior instability through isolated injury of the PCL [42]. Type 2 is defined as posterolateral rotational instability without lateral instability, characterized by injury to the PCL and the popliteus complex with an intact LCL and no arthroscopic gutter drive-through sign [42]. Type 3 is defined as posterolateral rotational instability with varus instability, characterized by injury to the PCL, the popliteus complex, and the LCL [42].

Other Considerations: In a modified classification of dorsolateral instabilities, Type A injuries show only rotational instability [42]. Type B injuries are defined by an additional lateral instability against varus forces with slight varus relaxation of 5–10° [42]. Type C injuries are defined by an additional lateral instability against varus forces with severe varus relaxation > 10° [42]. The PFL reconstruction is a good method to treat type A posterolateral knee instability [129].

Clinical Presentation

Diagnostic Challenges and Missed Injuries

Posterolateral corner injuries are frequently part of multiligament patterns [30]. The common association with injuries of other knee-stabilizing structures makes clinical evaluation difficult because the absence of different structures can complicate diagnosis [28]. In chronic cases of irreducible posterolateral knee dislocation, the classic dimple sign may be absent [31].

Physical Examination

Whenever suspecting a posterolateral complex injury, one has to carefully perform a valgus stress test in 0 and 30 degrees [22]. The dial test may not clinically detect posterolateral instability with injuries to only 1 or 2 posterolateral structures [32]. The posterolateral rotatory drawer maneuver is indicated for knee sprains with possible posterolateral corner tears and has no contraindications [28]. In this maneuver, the tibial lateral plateau must move posterior to the lateral femoral condyle [28].

In a series of acute grade III posterolateral corner injuries, examination with the patient under anesthesia showed tibial external rotation of greater than 10° in 84% of patients [102]. In the same series, examination with the patient under anesthesia showed positive varus instability in 73% of patients [102].

Imaging

MRI is a sensitive measure of cruciate and collateral ligament injury in acute knee dislocation; however, it does not reliably diagnose injury to the posterolateral corner or meniscus [21]. A higher index of suspicion is required during arthroscopy to prevent misdiagnosis of posterolateral corner or meniscus injury which could affect long-term clinical outcome [21]. MRI findings, including direct signs like fiber discontinuity and indirect signs like bone contusions, correlate well with arthroscopic findings for ACL, PCL, and posterolateral corner injuries [43]. Stress radiographs support accurate diagnosis of complex knee injuries and provide an objective measure of knee stability following ligament reconstruction [45]. In a series of acute grade III posterolateral corner injuries, 82% of patients with femoral peel-off lesions showed conclusive MRI signs of femoral insertion separation and discontinuity [102].

Injury Patterns and Associations

The study suggests progressive damage to translational and rotational knee soft-tissue restraints with increasing knee hyperextension [25]. In a series of 48 acute grade III posterolateral corner injuries, 40% of patients were surgically verified as having femoral peel-off lesions [102]. In a series of acute grade III posterolateral corner injuries, arthroscopic findings of acute avulsion and a positive lateral gutter drive-through sign were found in 94% of patients with femoral peel-off lesions [102]. Isolated PCL injuries are common, although the injury is most commonly associated with other ligament injuries [127].

Investigations

Clinical Examination

A comprehensive ligamentous examination combined with MRI constitutes the diagnostic benchmark for posterolateral corner injuries [23]. Clinicians must interpret physical findings with caution, as the dial test may fail to detect posterolateral instability when only one or two posterolateral structures are injured [32]. Furthermore, the classic dimple sign may be absent in cases of chronic irreducible posterolateral knee dislocation [31].

Imaging

MRI: Magnetic resonance imaging is an essential component of the diagnostic workup, serving as the imaging counterpart to the comprehensive ligamentous examination that defines the diagnostic benchmark for these injuries [23].

Treatment

Non-Operative

The provided evidence does not support specific conservative management protocols such as weight loss, physical therapy, NSAIDs, or injections for posterolateral corner injuries.

Operative

Indications: Injuries to the posterolateral corner, whether isolated or combined, are best treated by reconstructing the posterolateral corner along with the coexisting cruciate ligament injury if combined [5]. A one-stage protocol with early surgery rather than delayed reconstruction produced better clinical outcomes for multiligament injured knees [13]. MRI does not reliably diagnose injury to the posterolateral corner, requiring a higher index of suspicion during arthroscopy to prevent misdiagnosis [21].

Surgical Approach / Technique: Higher success rates are observed in reconstruction techniques of acute posterolateral corner knee injuries as compared to repair [29]. The described operative treatment of acute posterolateral rotatory instability resulted in a high percentage of good objective and subjective results with no subsequent reconstructive procedures for ligament instability being required [18]. Injury to the biceps femoris muscle occurred in eight of the seventeen knees included in a study of acute posterolateral rotatory instability, a structure often not appreciated initially because the iliotibial band is intact [18]. By using arthroscopically assisted reconstruction of the cruciate ligaments and the posterolateral corner for traumatic knee dislocation, 80% of patients had good subjective results and functional stability [17]. According to the IKDC scale, 45% of knees were nearly normal, 45% were abnormal, and 10% were severely abnormal following arthroscopically assisted reconstruction of cruciate ligaments and the posterolateral corner [17]. In a retrospective multicenter study of 53 patients with combined cruciate ligament and posterolateral corner injuries, posterolateral laxity was corrected in all but two cases [53]. In a retrospective multicenter study of 53 patients with combined cruciate ligament and posterolateral corner injuries, all sedentary workers and 86.7% of non-sedentary workers could return to work [53]. Outcomes of multiligament knee injuries might be negatively influenced by the need for posterolateral corner reconstruction [55]. Surgical treatment of knee dislocations provided satisfactory subjective and objective outcomes at two to six years postoperatively [56]. A systematic approach to chronic posterolateral instability of the knee combining bony axial correction, collateral and central ligament reconstruction can result in significant amelioration of function and positive outcomes for ADL and low level athletic activities [48]. The results demonstrate the effectiveness of the procedure for the correction of chronic posterolateral rotatory instability [124]. The technique of arthroscopic reconstruction of the popliteus complex could be clinically relevant for future arthroscopic posterolateral corner reconstructions [6]. Anatomic reconstruction of the posterolateral corner restores lateral stability clinically at 2 years' follow-up [35]. Both fibular-based and tibiofibular-based constructs for posterolateral corner reconstruction had comparable clinical outcomes and were equally effective in restoring varus and rotational stability [130].

Complications

Instability: Missed posterolateral corner injuries increase failure rates for cruciate ligament reconstructions [1] and lead to chronic disability [1]. Anatomic posterolateral corner reconstruction restores external rotation stability in the majority of patients [27], though it could not restore varus laxity in all patients [27]. In a study of 53 patients with combined cruciate ligament and posterolateral corner tears, posterolateral laxity was corrected in all but two cases [53].

Functional Outcomes: Long-term functional results for surgical treatment of injured posterolateral structures have been only moderately successful [14]. In a series of 39 patients with multiligament knee injuries, no significant difference was found for functional scores between acute posteromedial corner and posterolateral corner subgroups [13]. Subjective outcomes tended to be better in the acute than in the chronic reconstruction subgroup for posterolateral corner injuries [13]. In a study of 53 patients with combined cruciate ligament and posterolateral corner tears, the job had to be changed in 10% of cases overall [53], and in 25% of cases for laborers [53].

Other Considerations: In a study of knee dislocations with lateral side injury, patients who had delayed surgery (greater than 4 weeks from time of injury) to repair the lateral side had much less predictable outcomes than those who had early surgery [140]. These patients frequently had lower subjective and objective scores than those who had early surgery [140]. Three of four patients who experienced residual ligamentous laxity were in the group that had delayed surgery [140]. Patients who underwent delayed surgery and subsequently had ligamentous laxity had lower subjective scores when compared with patients who underwent early surgery [140]. MRI does not reliably diagnose injury to the posterolateral corner [21] or to the meniscus in the setting of acute knee dislocation [21].

Recovery

Light activity (weeks): The provided evidence does not specify a typical week range for the resumption of 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, or final functional outcomes.

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

Functional milestones: Subjective outcomes tend to be better in the acute reconstruction subgroup than in the chronic reconstruction subgroup [13]. In an arthroscopically assisted reconstruction series, 80% of patients achieved good subjective results and functional stability [17]. According to the IKDC scale in that same series, 45% of knees were nearly normal, 45% were abnormal, and 10% were severely abnormal [17]. Patients who underwent staged cruciate reconstruction(s) recorded higher subjective outcome scores than those with untreated cruciate injuries [153]. At two years post-operatively, patients undergoing subacute reconstruction demonstrated significantly better outcomes in terms of the Lysholm score and Tegner activity level compared to those undergoing delayed reconstruction [156].

Other Considerations: Full reconstruction is the best strategy for patients with combined ACL and posterolateral corner injuries [2]. Reconstruction is used rather than repair in the majority of patients sustaining posterolateral corner tears after high-energy injuries [3]. Recent studies suggest no advantage of double-bundle posterior cruciate ligament reconstruction in the setting of concomitant posterolateral corner repair [10], while suggesting a possible advantage in the setting of subtle posterolateral corner injury [10]. Long-term functional results for repair and reconstruction of injured posterolateral structures have been only moderately successful [14]. Anatomical reconstruction of the posterolateral corner restores external rotation stability in the majority of patients [27], although varus laxity could not be restored in all patients [27]. The technique for anatomic posterolateral corner reconstruction restores lateral stability clinically at two years' follow-up [35]. Following anatomic reconstruction after multiligament knee injuries, all patients had a stable posterior cruciate ligament at most recent clinical follow-up [59], and 77% of patients had no laxity at all at most recent clinical follow-up following anatomic posterior cruciate ligament reconstruction [59]. Patients with a previous history of knee ligament surgery had a significantly worse quality of life relative to those with no history of knee ligament surgery [60]. This study shows good functional results after reconstruction for isolated rupture of the posterior cruciate ligament [144]. A longer interval from injury to surgical reconstruction is associated with higher rates of articular cartilage lesions, with an increase in compartments affected [154]. The presence of a frank dislocation, delay in surgery, and duration of follow-up were found to influence outcomes in KD3 multiligamentous knee injuries [155].

Key Evidence

  • [L5] Prompt recognition of posterolateral corner injuries is critical because missed injuries increase failure rates for cruciate ligament reconstructions and lead to chronic disability. [1] (10.5435/00124635-200808000-00012)
  • [L3] Full reconstruction seems the best strategy in patients with combined ACL/posterolateral corner injuries. [2] (10.1016/j.otsr.2014.09.010)
  • [L2] The authors now use reconstruction rather than repair in the majority of patients who sustain posterolateral corner tears after high-energy injuries. [3] (10.1177/0363546504271208)
  • [L5] A combined posterior cruciate ligament and posterolateral corner reconstruction can restore intact knee kinematics at time zero. [4] (10.1177/0363546504268039)
  • [L4] Injury to the posterolateral corner, whether isolated or combined, is best treated by reconstructing the posterolateral corner along with the coexisting cruciate ligament injury if combined. [5] (10.1016/j.otsr.2014.07.032)
  • [L5] The technique could be clinically relevant for future arthroscopic posterolateral corner reconstructions. [6] (10.1007/s00167-014-3000-y)
  • [L2] Repair of the posterolateral corner may yield higher revision rates compared with reconstruction. [7] (10.1016/j.arthro.2009.01.008)
  • [L3] Anatomic posterolateral corner reconstruction with autografts provided superior stability compared to non-anatomic reconstruction in the setting of combined grade 3 posterolateral corner injuries and single bundle posterior cruciate ligament reconstruction. [8] (10.1016/j.jisako.2025.100646)
  • [L3] Anatomic posterolateral corner reconstruction with autografts provided superior stability compared to non-anatomic reconstruction in the setting of combined grade 3 posterolateral corner injuries and single bundle posterior cruciate ligament reconstruction. [9] (10.1177/2325967124s00443)
  • [L1] Recent studies of rotational stability suggest no advantage of double-bundle reconstruction in the setting of concomitant posterolateral corner repair but suggest a possible advantage in the setting of subtle posterolateral corner injury. [10] (10.1016/j.arthro.2008.11.006)
  • [L5] Both surgical techniques for anatomical posterolateral corner reconstruction showed good results in the static laxity tests. [11] (10.1177/0363546505278302)
  • [L4] Injuries to the posteromedial corner are common in the setting of traumatic knee dislocations. [12] (10.1007/s00167-009-1011-x)
  • [L4] [13] (10.1007/s00167-016-4067-4)
  • [L5] Numerous surgical techniques have been described for both repair and reconstruction of the injured posterolateral structures; however, long-term functional results have been only moderately successful. [14] (10.5435/00124635-200003000-00004)
  • [L5] The posterior oblique ligament (POL) is the predominant structure in the posteromedial corner of the knee joint, and surgical reconstruction should be considered the gold standard treatment in case of injury. [15] (10.1302/2058-5241.6.200127)
  • [L5] Injured posterolateral structures should be repaired before fixation of anterior cruciate ligament grafts. [16] (10.1177/03635465020300060701)
  • [L4] By using the described method of arthroscopically assisted reconstruction of the cruciate ligaments and the posterolateral corner, 80% of the patients had good subjective results and functional stability, and according to the IKDC scale, 45% of knees were nearly normal, 45% were abnormal, and 10% were severely abnormal. [17] (10.1016/j.arthro.2012.11.021)
  • [L4] [18] (10.2106/00004623-198365050-00005)
  • [L5] Most isolated medial collateral ligament injuries are treated nonsurgically, while concomitant damage to the anterior or posterior cruciate ligaments is a common indication for surgical management of high-grade injuries. [19] (10.5435/00124635-200903000-00004)
  • [L4] This study presents mid-term outcomes of one of the largest series of consecutive multi-ligament knee injuries reported to date. [20] (10.1016/j.arthro.2013.07.137)
  • [L2] MRI is a sensitive measure of cruciate and collateral ligament injury in acute knee dislocation; however, it does not reliably diagnose injury to the posterolateral corner or meniscus, and therefore, a higher index of suspicion is required during arthroscopy to prevent misdiagnosis which could affect long-term clinical outcome. [21] (10.1007/s00167-015-3857-4)
  • [L5] Whenever suspecting a posterolateral complex injury, one has to carefully perform a valgus stress test in 0 and 30 degrees. [22] (10.1016/j.injury.2006.03.009)
  • [L5] [23] (10.5435/jaaos-d-23-00278)
  • [L3] No effect of popliteal tendon reconstruction was found in anatomic posterolateral corner reconstruction on the stability and clinical results. [24] (10.1177/0363546511415656)
  • [L5] The study suggests progressive damage to translational and rotational knee soft-tissue restraints with increasing knee hyperextension. [25] (10.1177/0363546507308189)
  • [L4] The anatomical reconstruction of the posterolateral corner provides restoration of external rotation stability in the majority of patients, but varus laxity could not be restored in all patients. [27] (10.1007/s00167-014-3369-7)
  • [Paper] [28] (10.1016/j.eats.2014.01.008)
  • [L4] [29] (10.1007/s00167-023-07582-x)
  • [L5] The article summarizes the epidemiology, anatomy, biomechanics, and diagnosis of posterolateral corner (PLC) injuries, noting that PLC injuries are frequently part of multiligament patterns and that anatomical structures like the popliteofibular ligament and arcuate ligament exhibit significant variability. [30] (10.1016/j.injury.2017.10.008)
  • [L4] The authors bring attention to the clinical, radiographic, and MRI findings associated with chronic irreducible posterolateral knee dislocation, noting that the classic dimple sign may be absent in chronic cases. [31] (10.1016/j.arthro.2005.12.046)
  • [L5] However, posterolateral instability with injuries to only 1 or 2 posterolateral structures may not be clinically detected by the dial test. [32] (10.1016/j.arthro.2007.12.003)
  • [L5] [33] (10.1016/j.arthro.2025.05.011)
  • [L4] The technique restores lateral stability clinically at 2 years' follow-up. [35] (10.1016/j.arthro.2009.11.019)
  • [L4] [42] (10.1007/s00402-020-03607-z)
  • [L4] MRI findings, including direct signs like fiber discontinuity and indirect signs like bone contusions, correlate well with arthroscopic findings for ACL, PCL, and posterolateral corner injuries, aiding in the diagnosis and surgical planning of knee pathologies. [43] (10.1016/j.csm.2013.03.004)
  • [L5] Stress radiographs support accurate diagnosis of complex knee injuries and provide an objective measure of knee stability following ligament reconstruction. [45] (10.1016/j.arthro.2020.11.001)
  • [L4] Instabilities due to tears of the lateral-compartment ligaments are less common but more easily overlooked and more disabling than medial-compartment instabilities. [47] (10.2106/00004623-197658020-00002)
  • [L4] A systematic approach to chronic posterolateral instability of the knee combining bony axial correction, collateral and central ligament reconstruction can result in significant amelioration of function and positive outcomes for ADL and low level athletic activities. [48] (10.1016/j.arthro.2013.07.136)
  • [L4] [53] (10.1016/j.otsr.2014.10.003)
  • [L3] Outcomes of MLKI might be negatively influenced by bicruciate ligament, meniscal, and cartilage injuries; treatment characteristics such as need for posterolateral corner or bicruciate ligament reconstruction, use of allografts, or need for meniscal repair may similarly diminish outcomes. [55] (10.1007/s00167-018-5053-9)
  • [L3] Surgical treatment of the knee dislocations in our series provided satisfactory subjective and objective outcomes at two to six years postoperatively. [56] (10.2106/jbjs.d.02711)
  • [Paper] Extra-articular anterolateral procedures have undergone a renaissance in combination with anterior cruciate ligament reconstruction in selected cases, but there is a clear need for more high-level clinical evidence to support their routine use. [57] (10.1016/j.csm.2017.07.008)
  • [L4] All patients had a stable posterior cruciate ligament at most recent clinical follow-up, and 77% had no laxity at all. [59] (10.1177/03635465030310020701)
  • [L4] Patients with a previous history of knee ligament surgery had a significantly worse quality of life relative to those with no history of knee ligament surgery. [60] (10.1177/2325967115s00073)
  • [L5] A graft that restores knee kinematics for an isolated posterior cruciate ligament deficiency is rendered ineffective and may be overloaded if the posterolateral structures are deficient. [100] (10.1177/03635465000280011801)
  • [L4] [102] (10.1016/j.arthro.2011.02.021)
  • [L1] Isolated PCL reconstruction, whether single-bundle or double-bundle, could not restore normal knee kinematics in the PCL/PLC-deficient knee. [123] (10.1007/s00167-017-4672-x)
  • [L4] The results demonstrate the effectiveness of the procedure for the correction of chronic posterolateral rotatory instability. [124] (10.2106/00004623-198567030-00001)
  • [L2] Isolated PCL injuries are common, although the injury is most commonly associated with other ligament injuries. [127] (10.1007/s00167-015-3786-2)
  • [L4] The PFL reconstruction is a good method to treat type A posterolateral knee instability. [129] (10.1007/s00167-009-0794-0)
  • [L4] Both constructs had comparable clinical outcomes and were equally effective in restoring varus and rotational stability for PLC knee injuries. [130] (10.1177/03635465221138548)
  • [Paper] The current MLKI classification system is now more than 20 years old and certainly represents an improvement over previous classification systems; however, it is our hope that by creating a classification system that includes each specific structure injured, modifiers for fractures, extensor mechanism injuries, nerve injuries, or vascular injuries, as well as specific anatomic location of structures injured meniscus and articular cartilage injuries, and injury timing (acute, chronic) that we can use this information to guide further research in this field and to ultimately improve patient care. [132] (10.1016/j.csm.2018.11.006)
  • [Paper] Despite limitations in validation, the Schenck classification serves as a useful communication, planning, and prognostic tool for evaluating potential associated neurovascular injuries in knee dislocations. [138] (10.1097/corr.0000000000001186)
  • [L4] [140] (10.1177/0363546507299444)
  • [L4] This study shows good functional results after reconstruction for isolated rupture of the posterior cruciate ligament. [144] (10.1007/s00167-010-1176-3)
  • [L4] Patients who underwent a staged cruciate reconstruction(s) had higher subjective outcome scores than those who had cruciate injuries left untreated. [153] (10.1177/23259671221131817)
  • [L4] A longer interval from injury to surgical reconstruction is associated with higher rates of articular cartilage lesions, with an increase in compartments affected. [154] (10.1007/s00167-015-3540-9)
  • [L3] The presence of a frank dislocation, delay in surgery, and duration of follow-up were found to influence outcomes. [155] (10.1177/2325967118794367)
  • [L3] At 2 years post-operatively, patients who underwent subacute reconstruction had a significantly better outcome in terms of the Lysholm score and Tegner activity level than patients who underwent delayed reconstruction. [156] (10.1007/s00167-010-1312-0)

See Also

References

[1] Posterolateral Corner Injury of the Knee: Evaluation and Management. Journal of the American Academy of Orthopaedic Surgeons. 2008. DOI: 10.5435/00124635-200808000-00012

[2] Management of combined anterior or posterior cruciate ligament and posterolateral corner injuries: A systematic review. Orthopaedics & Traumatology: Surgery & Research. 2014. DOI: 10.1016/j.otsr.2014.09.010

[3] The Posterolateral Corner of the Knee. The American Journal of Sports Medicine. 2005. DOI: 10.1177/0363546504271208

[4] Biomechanical Analysis of a Combined Double-Bundle Posterior Cruciate Ligament and Posterolateral Corner Reconstruction. The American Journal of Sports Medicine. 2005. DOI: 10.1177/0363546504268039

[5] Posterolateral knee reconstruction. Orthopaedics & Traumatology: Surgery & Research. 2015. DOI: 10.1016/j.otsr.2014.07.032

[6] Arthroscopic reconstruction of the popliteus complex: accuracy and reproducibility of a new surgical technique. Knee Surgery, Sports Traumatology, Arthroscopy. 2014. DOI: 10.1007/s00167-014-3000-y

[7] Decision Making in the Multiligament‐Injured Knee: An Evidence‐Based Systematic Review. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2009.01.008

[8] Anatomic Posterolateral Corner Reconstruction With Autografts Provides Superior Stability Compared to Non-Anatomic Reconstruction in the Setting of Combined Grade 3 Posterolateral Corner Injury and Single Bundle Posterior Cruciate Ligament Reconstruction. Journal of ISAKOS. 2025. DOI: 10.1016/j.jisako.2025.100646

[9] Anatomic posterolateral corner reconstruction with autografts provides superior stability compared to non-anatomic reconstruction in the setting of combined grade 3 posterolateral corner injury and single bundle posterior cruciate ligament reconstruction. Orthopaedic Journal of Sports Medicine. 2024. DOI: 10.1177/2325967124s00443

[10] Single‐Bundle Versus Double‐Bundle Posterior Cruciate Ligament Reconstruction. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2008.11.006

[11] Comparison of 2 Surgical Techniques of Posterolateral Corner Reconstruction of the Knee. The American Journal of Sports Medicine. 2005. DOI: 10.1177/0363546505278302

[12] Injury patterns to the posteromedial corner of the knee in high‐grade multiligament knee injuries: a MRI study. Knee Surgery, Sports Traumatology, Arthroscopy. 2009. DOI: 10.1007/s00167-009-1011-x

[13] Clinical outcomes after multiligament injured knees: medial versus lateral reconstructions. Knee Surgery, Sports Traumatology, Arthroscopy. 2016. DOI: 10.1007/s00167-016-4067-4

[14] Acute and Chronic Posterolateral Rotatory Instability of the Knee. Journal of the American Academy of Orthopaedic Surgeons. 2000. DOI: 10.5435/00124635-200003000-00004

[15] Posterior oblique ligament of the knee: state of the art. EFORT Open Reviews. 2021. DOI: 10.1302/2058-5241.6.200127

[16] The Influence of the Integrity of Posterolateral Structures on Tibiofemoral Orientation When an Anterior Cruciate Ligament Graft is Tensioned. The American Journal of Sports Medicine. 2002. DOI: 10.1177/03635465020300060701

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