您的感受¶
后交叉韧带损伤是指膝关节后方的韧带发生拉伸或撕裂。这种情况通常由胫骨前部受到撞击引起,例如膝盖撞击汽车仪表盘,或在脚尖朝下的情况下跌倒时膝盖弯曲着地。该韧带的运动损伤源于直接撞击或外部力量,而非导致其他膝关节韧带损伤的扭转和减速动作。
大多数此类损伤患者会感到膝关节疼痛、肿胀和僵硬。与某些其他膝关节韧带损伤不同,您在受伤当时可能没有听到“啪”的响声,且膝关节可能完全没有不稳定感。疼痛通常位于膝盖前方髌骨周围,或沿膝关节内侧或后方。这种疼痛往往在上下坡行走时显现。对膝关节前方施加负荷的日常活动,如上下楼梯或从低矮的椅子上起身,可能会引起不适。一些人在受伤后不久会注意到关节内出血,这会导致膝关节肿胀并产生紧绷感。
如果您的损伤时间较久或涉及膝关节的其他部位,情况可能会发生变化。有些人几乎感觉不到任何症状,而另一些人则感觉膝关节不稳,尤其是当膝关节外侧也受伤或您的双腿自然向外弯曲时。随着时间的推移,髌骨关节和膝关节内侧可能会发展出退行性关节炎,这就是为什么这些区域的持续疼痛值得关注。
实际发生了什么¶
在您的膝关节内部,两条强韧的韧带在关节中央相互交叉。位于后方的一条称为后交叉韧带,即PCL。您可以将其想象成一根粗绳,防止您的胫骨(小腿骨)在股骨(大腿骨)下方向后滑动。它在膝关节的每个角度下都发挥作用,无论是伸直还是弯曲状态,它还有助于稳定膝关节以抵抗侧向和扭转力。
PCL实际上由协同工作的两部分组成。当您的膝关节弯曲时,其中一部分会收紧;当您的膝关节伸直时,另一部分会收紧。当韧带被拉伸或撕裂时,其中一部分或两部分都会停止发挥作用,导致胫骨向后移位超过正常范围。这种松弛,加上它对膝关节前部和内侧施加的额外负荷,正是导致您上文读到的疼痛和僵硬的原因。
医生通过分级来描述韧带受损的严重程度。轻度分级意味着韧带被拉伸但仍保持连接,就像一根有几股纤维磨损的绳子。中度分级意味着韧带部分撕裂且比正常状态更松弛。重度分级意味着韧带完全撕裂,因此不再能固定胫骨的位置。轻度和中度损伤通常无需手术即可恢复,特别是如果膝关节其余部分完好无损的话。完全撕裂,或者伴有其他韧带或膝关节外侧角损伤的情况,更可能需要手术。
值得了解的是,这条韧带比膝关节前方更为人熟知的韧带更厚、更强壮,因此损伤它通常需要较大的外力。这也是为什么这些损伤往往伴随膝关节其他部位的损伤,以及为什么您的外科医生在决定您需要何种治疗之前,会仔细检查整个关节。
我们如何处理¶
大多数轻度和中度损伤无需手术即可恢复。我们首先进行理疗,以强化大腿前侧的肌肉,即股四头肌。该肌肉将胫骨向前固定,防止其向后塌陷,这是该韧带松弛时的主要问题。特殊的支具也有助于固定骨骼。对于轻度或中度损伤,大多数人可在 2 至 4 周内恢复运动。对于未进行手术的完全撕裂,通常需要在支具或石膏中将膝盖保持伸直状态 4 周,然后开始强化训练。通过持续的股四头肌锻炼,80% 的此类损伤无需手术即可达到良好效果。
当韧带完全断裂且膝盖持续疼痛或不稳定,或其他韧带同时受损时,需要考虑手术。如果多条韧带撕裂,我们通常建议尽早手术,而不是等待。手术会用一块新的组织(称为移植物)替换撕裂的韧带,从而再次固定胫骨。如果韧带撕裂时带下了一块骨片,则可以直接将该骨片复位固定。我们将在单独的页面详细介绍手术内容,并由您与我们共同决定是否适合您。
预期情况¶
对于轻度或中度损伤,预后通常较为稳定。通过强化锻炼,并在必要时使用支具,疼痛和肿胀通常在数周内而非数月内消退,许多人能迅速重返运动。非手术治疗的长期结果显示,患者能保持活跃状态,膝关节具有良好力量和完整活动范围。即使存在一定程度的松弛,也未必总是引起问题。部分存在持续性松弛的患者报告完全没有功能性困难。
完全撕裂则是另一回事。若不予处理,完全撕裂的韧带不会自行重新连接,且松弛倾向持续存在。多年来,这种额外的活动会对膝关节前部和内侧部分施加负荷,导致磨损性关节炎,因此该部位的持续疼痛具有重要意义。在儿童中,手术前等待时间过长会增加膝关节缓冲软骨受损的风险,这可能导致不良的长期预后。
如果确实需要手术,了解其能修复和不能修复的内容是值得的。韧带置换可改善膝关节感觉,并增加重返运动的可能性。在涉及多条韧带撕裂的损伤中,所有患者在最近一次复查时均拥有稳定的韧带,且 77% 的患者完全没有松弛。对于单独的完全撕裂,结果良好但并非完美:约半数膝关节的韧带完全恢复稳定,而部分患者保留轻度或中度松弛。涉及膝关节外侧角的联合损伤,其效果往往不如单一韧带损伤,且总体结果未达到膝关节前部韧带修复后的水平。在手术后的前 2 年内,无论重建一条还是多条韧带,失败率相似。大多数人保留了膝关节在空间中的自然本体感觉,且膝关节评分和松弛度在术后均有改善。
何时就医¶
如果您在胫骨前部受到撞击或跌倒时膝盖弯曲着地后出现膝关节疼痛、肿胀或僵硬,尤其是当膝关节迅速肿胀并因关节内出血而感到紧绷时,请咨询您的全科医生。如果膝盖前部、内侧或后部的疼痛在上下坡或楼梯时持续困扰您,或者您的膝盖开始感觉松动或打软腿(当膝盖其他部位也受伤时这种情况更有可能发生),请要求专科医生评估。如果您的膝盖脱位,或在跌倒或事故中多条韧带撕裂,请立即前往急诊科,因为膝盖后部的血管和神经可能受损,需要当天进行检查。如果您已经接受过该韧带的重建手术,且膝盖变得发热、发红、肿胀并伴有发热,也需要紧急评估。
Evidence & references
This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.
Anatomy & Pathophysiology¶
Bony Anatomy & Ligament Structure¶
- The PCL is stronger than the ACL [6].
- The PCL has a broader femoral attachment than the ACL [6].
- The PCL is an intrasynovial but extraarticular structure [7].
- The PCL has an extrasynovial location, which provides better healing potential [6].
- The PCL is composed of two major parts: a large anterolateral bundle (ALB) and a smaller posteromedial bundle (PMB) [7].
- The ALB forms the bulk of the ligament [7].
- The PMB runs obliquely to the back of the tibia [7].
- The PCL cross-sectional area increases from tibia to femur [7].
- The PCL is approximately 50% larger than the ACL at the femur [7].
- The PCL is approximately 20% larger than the ACL at the tibia [7].
- The meniscofemoral ligaments average approximately 22% of the entire cross-sectional area of the PCL [7].
- The PCL insertion sites are 300% to 500% larger than the cross section of the midsubstance [7].
- The femoral insertion of the PCL extends more than 20 mm from anterior to posterior [6].
- The ALB is more vertical than the PMB and inserts on the anterior roof of the intercondylar notch [6].
- The PMB is more oblique and inserts posteriorly on the lateral wall of the medial femoral condyle [6].
- The PCL and meniscofemoral ligaments cover almost all of the medial aspect of the intercondylar notch anterior to the medial intercondylar ridge [6].
- The anterior margin of the PCL is 2 mm from the articular cartilage [6].
- The bundle centers of the PCL are an average of 12 mm apart on the femur [6].
- The tibial insertion of the PCL is narrower than the femoral insertion [6].
- The tibial insertion is located in the posterior intercondylar fossa of the proximal tibia [6].
- The PCL tibial footprint extends from the medial meniscus root and the edge of the lateral plateau articular cartilage to a point 1 to 1.5 cm below the joint line [6].
- The most posterior distal fibers of the PCL consist of the thicker PMB [6].
- The PMB blends with the periosteum and posterior capsule to insert distal to the osseous ridge cradling the anterior proximal fibers of the ALB [6].
- The centers of the PCL bundles on the tibia are an average of 9 mm apart [6].
- The tibial attachment is in a depression 1.0 to 1.5 cm behind and below the intraarticular portion of the tibia [7].
- The tibial attachment slips usually blend with the posterior horn of the lateral meniscus, the meniscofemoral ligaments of Humphrey and Wrisberg [7].
- The center of the femoral insertion of the ALB is 7.4 mm from the trochlear point [7].
- The center of the femoral insertion of the ALB is 11.0 mm from the medial arch point [7].
- The center of the femoral insertion of the ALB is 7.9 mm from the distal articular cartilage [7].
- The center of the tibial attachment site is 6.1 mm from the shiny white fibers of the posterior medial meniscus root [7].
- The center of the tibial attachment site is 4.9 mm from the bundle ridge [7].
- The center of the tibial attachment site is 10.7 mm from the “champagne glass” drop-off [7].
- The bundle ridge is horizontal and separates the ALB from the PMB [7].
- The ALB is bordered medially and posteriorly by the PMB [7].
- At its femoral insertion, the PMB is bordered by the medial intercondylar ridge proximally, the ALB anteriorly, and the anterior meniscofemoral ligament distally [7].
- The center of the PMB femoral attachment is 11.1 mm from the medial arch point [7].
- The center of the PMB femoral attachment is 10.8 mm from the posterior point of the articular cartilage margin [7].
- The tibial attachment of the PMB is more compact than the ALB [7].
- The PMB fans out in its attachment border along the posteromedial aspect of the ALB [7].
- The thickest portion of the PMB, including the functional center of the bundle, is located posteromedial to the ALB [7].
- The functional center of the PMB is 3.1 mm lateral from the medial groove of the medial tibial plateau articular surface [7].
- The functional center of the PMB is 4.4 mm anterior to the champagne glass drop-off [7].
- The PCL originates on the posteromedial aspect of the intercondylar notch and inserts into the posterior sulcus of the tibia between the medial and lateral joint surfaces [9].
Biomechanics & Function¶
- The primary function of the PCL is to resist posterior displacement of the tibia in all knee flexion angles [6].
- The PCL is a secondary varus, valgus, and rotational stabilizer [6].
- The PCL facilitates internal rotation of the tibia at higher flexion angles [6].
- The ALB carries more load in flexion [6].
- The PMB carries more load in extension [6].
- The anterolateral fibers are taut in flexion [9].
- The posteromedial fibers are taut in extension [9].
- With flexion, there is tightening of the bulk of the ligament (ALB) but less tension on the small band (PMB) [7].
- The PCL is associated with the meniscofemoral ligaments of Humphrey (anterior) and Wrisberg (posterior) [6].
- The PCL is the primary restraint to posterior tibial translation in the intact knee [1].
Mechanism of Injury¶
- A direct blow to the proximal aspect of the tibia is the most common cause of PCL injury [1].
- In athletes, the mechanism of injury is usually a fall onto the flexed knee with the foot plantarflexed [1].
- This athletic mechanism places a posterior force on the tibia and subsequently causes rupture of the PCL [1].
- In high-energy trauma such as motor vehicle accidents, the PCL is often injured with other capsuloligamentous structures [1].
- The most common mechanisms of injury are a direct blow to the anterior tibia with the knee flexed or a fall into the ground with the foot plantar flexed [3].
- The “dashboard” injury involves the anterior tibia sustaining a posteriorly directed force from the dashboard with the knee in 90 degrees of flexion [3].
- Sports injuries to the PCL result from an outside force or blow, in contrast to the typical deceleration twisting mechanism of ACL injuries [3].
- The most common mechanism for isolated PCL injury in the athlete is a partial tear associated with hyperflexion of the knee [3].
- Significant multiligamentous knee injuries with PCL tears can occur after a varus or valgus stress is applied to the hyperextended knee [3].
- PCL injury usually occurs from a motor vehicle accident (dashboard injury) or during athletic activities [9].
- In athletic injuries, the typical mechanism is a fall onto a flexed knee while the foot is in a plantar flexed position [9].
- A direct blow to the anterior aspect of the tibia while the knee is flexed may result in a tear of the PCL [9].
- PCL injuries are associated with more severe traumas that cause a knee dislocation or a multi-ligamentous injury including a posterolateral corner injury [9].
Associated Injuries & Pathology¶
- Injuries to the PCL may be isolated or combined with other capsuloligamentous injuries in the knee [1].
- When three or more ligamentous structures are injured, the injury should be viewed as a dislocated knee and the vascular status of the injured limb should be assessed [1].
- Injury to the posterolateral structures has been reported to occur in up to 60% of PCL injuries [3].
- Concomitant injuries are common with PCL injury, including posterolateral corner and meniscus injuries [3].
- The natural history of certain PCL injuries, especially combined ones, will progress to instability, pain, and osteoarthritis of the knee [1].
- This progression to osteoarthritis is especially noted in the patellofemoral and medial tibiofemoral compartments [1].
- Patients with significant varus alignment or injury to the lateral structures of the knee will often complain of feelings of instability and giving way [3].
- In contrast to an ACL tear, it is rare for patients with PCL injuries to report hearing a “pop” or report any feelings of subjective instability [3].
- Patients with PCL injuries more commonly complain of knee pain, swelling, and stiffness [3].
- The presentation of a subacute or chronically injured PCL can range from asymptomatic to significant instability and pain [3].
- Specific cues to PCL injury on initial inspection include abrasions or ecchymosis around the proximal anterior tibia and ecchymosis in the popliteal fossa [3].
- Subtle posterior subluxation on the lateral radiograph may indicate PCL injury [3].
- In the chronic setting of PCL injury, radiographs are useful to assess for patellofemoral and medial compartment degenerative changes [3].
Classification¶
- PCL injuries occur in isolation or in combination with other injuries [1].
- The grades of PCL injuries are based on physical examination and MRI findings [1].
- A partial PCL injury is characterized by posterior tibial translation of less than 10 mm on the posterior drawer test with the knee in neutral rotation [1].
- A partial PCL injury is characterized by the presence of an end point on the posterior drawer test [1].
- A complete isolated PCL injury is characterized by posterior tibial translation of 8–10 mm on the posterior drawer test with the knee in neutral rotation [1].
- In a complete isolated PCL injury, posterior tibial translation is diminished with the knee in internal rotation [1].
- A combined PCL and capsuloligamentous injury is characterized by posterior tibial translation greater than 10 mm on the posterior drawer test with the knee in neutral rotation [1].
- In a combined PCL and capsuloligamentous injury, the PCL is injured in conjunction with other structures such as the ACL, posterolateral corner, or medial side [1].
- A grade I PCL injury is defined by a step-off of less than 1 cm between the tibial plateau and femoral condyle at 90° of flexion, with the tibial plateau remaining anterior to the femoral condyle [1].
- A grade II PCL injury is defined by the tibial plateau being flush with the femoral condyle at 90° of flexion [1].
- A grade III PCL injury is defined by the tibial plateau being posterior to the femoral condyle at 90° of flexion [1].
- A grade I PCL injury on the posterior drawer test is defined by 3 to 5 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- A grade II PCL injury on the posterior drawer test is defined by 6 to 10 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- A grade III PCL injury on the posterior drawer test is defined by greater than 10 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- The degree of posterior tibial translation may decrease with internal tibial rotation in partial tears [1].
- A combined PCL and capsuloligamentous injury is indicated by more than 15 mm of posterior translation with the knee at 90° and in neutral rotation [1].
- A combined PCL and capsuloligamentous injury is indicated by more than 10 mm of posterior translation with the knee in internal rotation [1].
Clinical Presentation¶
History and Mechanism of Injury¶
- In athletes, the mechanism of injury is usually a fall onto the flexed knee with the foot plantarflexed, which places a posterior force on the tibia [1].
- The "dashboard" injury involves a posteriorly directed force to the anterior tibia with the knee in 90 degrees of flexion [3].
- Sports injuries to the PCL result from an outside force or blow, contrasting with the typical deceleration twisting mechanism of ACL injuries [3].
- Significant multiligamentous knee injuries with PCL tears can occur after varus or valgus stress is applied to the hyperextended knee [3].
- It is rare for patients with PCL injuries to report hearing a “pop” or report feelings of subjective instability [3].
- Patients with PCL injuries commonly complain of knee pain, swelling, and stiffness [3].
- Patients with significant varus alignment or injury to the lateral structures of the knee often complain of feelings of instability and giving way [3].
- An isolated PCL injury may be less obvious than a combined injury because instability is often subtle or even asymptomatic [1].
Physical Examination¶
- The posterior drawer test is the primary dynamic test to diagnose a PCL injury [1].
- The posterior drawer test is performed with the knee flexed to 90 degrees and a posteriorly directed force applied to the anterior tibia [3].
- In a grade I PCL injury, the step-off between the tibial plateau and femoral condyle is < 1 cm but the tibial plateau remains anterior to the femoral condyle [1].
- In a grade II PCL injury, the tibial plateau is flush with the femoral condyle [1].
- In a grade III PCL injury, the tibial plateau is posterior to the femoral condyle [1].
- A grade I injury on posterior drawer test is defined as 3 to 5 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- A grade II injury on posterior drawer test is defined as 6 to 10 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- A grade III injury on posterior drawer test is defined as >10 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- The quadriceps-active test is positive when the tibia translates anteriorly at 90° of flexion with resisted knee extension [1].
- The posterior sag or Godfrey test involves flexing the knee and hip and noting the posterior pull of gravity creating posterior “sag” of the tibia on the femur [3].
- An adjunct to the posterior sag test involves watching for a reduction of subluxation with active quadriceps contraction [3].
- The reverse pivot shift test is performed by placing a valgus stress on the knee with the foot externally rotated and extending from 90 degrees of flexion [3].
- A palpable reduction of the posterolateral tibial plateau is noted between 20 and 30 degrees of flexion during the reverse pivot shift test [3].
- Evaluation of ACL laxity in the presence of an acute PCL injury is challenging due to the lack of a stable reference point for Lachman or anterior drawer tests [3].
Imaging¶
- Plain radiographs are important initially to rule out fractures and avulsions [1].
- Plain radiographs are essential to evaluate for bony injuries, dislocation, or evidence of other associated injuries given the magnitude of forces required to injure the PCL [3].
- Stress posterior drawer radiographs and contralateral comparisons may increase the sensitivity for detecting PCL injuries with plain radiographs [3].
- MRI has been shown to have a very high sensitivity and specificity in diagnosing a PCL injury [1].
- MRI has been reported to be 96–100% sensitive at diagnosing PCL tears [3].
- MRI helps determine the site and degree of injury by assessing the continuity of the PCL [1].
- MRI may indicate the presence of other meniscal, chondral, or ligamentous injuries which may influence treatment strategies [1].
- MRI is valuable in detecting associated injuries, particularly posterolateral corner injuries that can be missed on initial clinical examination [3].
- In multiligamentous knee injuries, MRI can be used to assess the ACL as clinical examination of the ACL is challenging in the setting of a complete PCL tear [3].
Investigations¶
History and Mechanism¶
- The history of injury helps differentiate between high- and low-energy traumas [1].
- Concurrent injuries such as knee dislocation, neurovascular injury, and additional ligamentous or skeletal injuries assist in the evaluation [1].
- Patients with PCL injuries rarely report hearing a "pop" or feelings of subjective instability, unlike ACL tears [3].
- Sports injuries to the PCL result from an outside force or blow, contrasting with the deceleration twisting mechanism of ACL injuries [3].
Physical Examination¶
- The physical examination is specific for PCL injury and is classified based on the degree of injury [1].
- At 90° of flexion, there is normally a 1-cm step-off between the tibial plateau and femoral condyle [1].
- In a grade I injury, the step-off is < 1 cm but the tibial plateau remains anterior to the femoral condyle [1].
- In a grade II injury, the tibial plateau is flush with the femoral condyle [1].
- In a grade III injury, the tibial plateau is posterior to the femoral condyle [1].
- The posterior drawer test is the primary dynamic test to diagnose PCL injury [1].
- Grade I PCL injury on posterior drawer test is defined as 3 to 5 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- Grade II PCL injury on posterior drawer test is defined as 6 to 10 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- Grade III PCL injury on posterior drawer test is defined as >10 mm of increased posterior tibial translation compared with the uninvolved knee at 90° of flexion [1].
- The Lachman test for ACL injury, varus and valgus laxity testing, and assessment of external and internal tibial rotation differences are critical in differentiating between isolated and combined injuries [1].
- An adjunct to the posterior sag test involves watching for a reduction of this subluxation with active quadriceps contraction [3].
- The reverse pivot shift is performed by placing a valgus stress on the knee with the foot externally rotated and extending from 90 degrees of flexion, noting a palpable reduction of the posterolateral tibial plateau between 20 and 30 degrees of flexion [3].
- The accuracy, sensitivity, and specificity of clinical examination findings for PCL injury are greater than 90% [14].
- In a simplified grading system, a grade A injury presents with a slight loss of anterior tibial offset at 90° of flexion [14].
- In a simplified grading system, a grade B injury presents with the tibia flush with the femoral condyles at 90° of flexion [14].
- In a simplified grading system, a grade C injury presents with tibial displacement posterior to the femoral condyles at 90° of flexion [14].
- Grades A, B, and C injuries correlate with grades I, II, and III injuries when considering treatment options and outcomes [14].
Imaging¶
- Radiographs can reveal PCL tibial avulsion injury, capsular avulsion, or associated fracture as well as posterior resting position and subluxation of the tibia [14].
- Stress radiographs can be used to assess PCL disruption [14].
- MRI complements the history and physical examination and helps determine the site and degree of injury by assessing the continuity of the PCL [1].
- MRI is extremely valuable in its ability to detect associated injuries, particularly posterolateral corner injuries which can often be missed on initial clinical examination [3].
- MRI is used to determine the location and severity of PCL disruption and shows concomitant meniscal, osteochondral, chondral, and ligament injuries [14].
- If grade III posterior tibial laxity is present and radiographs show more than 10 mm of posterior subluxation, a combined PCL and posterolateral corner injury should be suspected [14].
Treatment¶
Nonsurgical¶
- Nonsurgical treatment is reserved for isolated partial PCL injuries with <10 mm of increased posterior tibial translation [1].
- Conservative management for PCL injuries focuses on quadriceps strengthening to prevent posterior tibial sag [17].
- Return to sports is usually achieved in 2 to 4 weeks for grade I–II PCL injuries [17].
- Treatment for grade III PCL injuries includes relative immobilization in extension for 4 weeks [17].
- Special braces have been designed to prevent posterior sag in PCL injuries [17].
- Chronic PCL deficiency can lead to increased contact pressures in the patellofemoral and medial compartment of the knee [17].
- Nonsurgical treatment is recommended for patients with an isolated grade I or II PCL injury [19].
- The nonsurgical program for isolated grade I or II PCL injuries includes extension bracing treatment, protected weight bearing, and quadriceps strengthening rehabilitation [19].
- Two natural history studies of nonsurgically treated isolated grade I or II PCL injuries found good subjective and objective outcomes with no functional deterioration [19].
- Two natural history studies of nonsurgically treated isolated grade I or II PCL injuries found 97% quadriceps and 93% hamstring strength [19].
- A 7-year follow-up study reported that 92% of patients with grade I or II PCL injuries had a good to excellent result after nonsurgical management based on the Tegner Activity Level Scale and Lysholm-II Knee Questionnaire scores [19].
- Shelbourne and Muthukaruppan reported good clinical outcomes when partial PCL injuries with 1+ to 2+ posterior laxity were treated conservatively initially [18].
- Conservative treatment for partial PCL injuries consists of knee extension and a protective rehabilitation program with no active hamstring strengthening [18].
- Long-term results for conservatively treated isolated PCL injuries did not correlate with the initial degree of instability [18].
- Subjective scores for conservatively treated isolated PCL injuries did not deteriorate with time [18].
Surgical Indications¶
- Surgical treatment is indicated in patients with symptomatic isolated PCL tears [17].
- Surgical treatment is indicated in patients with PCL avulsion fractures [17].
- Surgical treatment is indicated in the setting of a multiligament injured knee [17].
- Surgical treatment is recommended for a chronic grade III PCL lesion if the patient is symptomatic [19].
- PCL injuries with 3+ laxity (≥ 8 mm on stress radiographs) are reconstructed [18].
- Symptomatic PCL injuries are reconstructed [18].
Surgical Techniques¶
- Primary repair or open reduction and internal fixation is performed for PCL avulsion injuries [17].
- Reconstruction is performed for PCL injuries other than avulsion injuries [17].
- Options for PCL reconstruction include tibial inlay versus transtibial, single-bundle versus double-bundle, and autograft versus allograft [17].
- The tibial inlay technique theoretically reduces the “killer turn” between the posterior border of the tibial plateau and the graft [17].
- The reduction of the “killer turn” by the tibial inlay technique may decrease failure rates [17].
- Double-bundle PCL reconstruction is theoretically stronger than single-bundle reconstruction [17].
- Double-bundle PCL reconstruction may be beneficial in the revision setting or with multiple ligament reconstruction [17].
- There has been no evidence to suggest one PCL reconstruction technique is superior over another [17].
- The results of PCL reconstruction are less favorable than primary repair of avulsion fractures as residual posterior laxity often exists [17].
- An osteotomy should be considered in the setting of malalignment for PCL injuries [17].
- A high tibial osteotomy can treat varus malalignment as well as increase tibial slope to help reduce posterior tibial sag [17].
- Avulsion of the PCL usually occurs at the femoral attachment and can be repaired using suture anchors or femoral bone tunnels [19].
- Large osseous avulsion fragments from the tibial attachment can be repaired with open reduction and screw-and-washer fixation [19].
- The tibial inlay technique is usually performed through an open posterior approach [19].
- In the tibial inlay technique, the bone block is recessed and fixed with an interference screw at the posterior tibia, ensuring to avoid graft protrusion [19].
- Advantages of the tibial inlay technique include osseous graft healing, avoidance of so-called killer turn stresses, decreased graft wear, and improved graft biomechanics [19].
- An arthroscopic inlay technique using suture button fixation over the tibial-side bone block has been described as combining the advantages of arthroscopic and inlay techniques [19].
- In the transtibial technique, the tibial tunnel is reamed from anterior to posterior through the tibia under direct arthroscopic and fluoroscopic visualization [19].
- The tibial footprint for the transtibial technique is approximately 7 mm anterior to the posterior tibial cortex as seen on a perfect lateral image [19].
- Cadaver biomechanical data revealed no difference between transtibial and tibial inlay techniques when grafts were appropriately pretensioned before insertion [19].
- Multiple studies report no difference in functional, radiographic, or clinical outcomes between transtibial and tibial inlay techniques [19].
- Multiple studies report no difference in functional, radiographic, or clinical outcomes between arthroscopic and open PCL reconstruction techniques [19].
- Biomechanical comparison studies concluded that double-bundle PCL reconstruction is preferable for decreasing posterior tibial translation and improving rotational restraint [19].
- Biomechanical advantages of double-bundle PCL reconstruction were not correlated with superior clinical outcomes [19].
- Isolated single-bundle PCL reconstruction yields good long-term results without functional differences in comparison with double-bundle reconstruction [19].
- Double-bundle reconstructions have gained favor with many surgeons, but anatomic single-bundle techniques have good results similar to those for transtibial and inlay techniques [18].
- The two-tunnel technique has been shown in clinical studies to have increased stability and to better fill the large PCL footprint [18].
- The single-tunnel technique is used mostly for reconstruction of multiple knee ligaments in knee dislocations [18].
- The two-tunnel technique is used primarily in isolated PCL reconstruction [18].
- An Achilles tendon allograft is the preferred graft source for PCL reconstruction in the described protocol [18].
- Comparable results have been reported with allografts and autografts for PCL reconstruction [18].
- An all-arthroscopic inlay procedure using a retrocutting reamer and a closed-ended tibial tunnel with suture fixation anteriorly produces a shorter, stiffer graft construct [18].
- The all-arthroscopic inlay procedure removes the “killer curve” that sometimes occurs in the transtibial technique, although a killer curve still remains on the femoral side [18].
- Comparative studies show that anatomic single-tunnel and inlay procedures produce equal function and stability [18].
- Double-bundle PCL techniques have been shown to be slightly better than single-bundle techniques with 2.5 mm of posterior displacement compared with 3.2 mm [18].
- Double-bundle PCL techniques have been shown to have better IKDC scores in most studies [18].
- The most important factors for long-term success in PCL reconstruction are correction of associated instabilities and meniscal preservation [18].
- Slow, protected rehabilitation increases the likelihood of knee stability and should emphasize early maintenance of knee extension, delayed weight bearing, and delayed return to sports [18].
- LaPrade et al. showed that a decreased posterior tibial slope puts athletes at some increased risk of PCL injuries [18].
- With double-bundle PCL reconstruction, there is no increased failure rate based on tibial slope [18].
Postoperative Rehabilitation¶
- Postoperative rehabilitation for PCL surgery consists of early immobilization in extension and protection against gravity [17].
- Early range of motion should be performed in the prone position [17].
- The focus of postoperative rehabilitation is on quadriceps strengthening [17].
- Resisted hamstring strengthening should be avoided early in rehabilitation because the posterior pull increases stress on the graft [17].
Complications¶
- Posterior laxity increases over time after PCL reconstruction [2].
- Tibial slope strongly influences knee stability after posterior cruciate ligament reconstruction [2].
- Consequences of tibial tunnel reaming on the meniscal roots during cruciate ligament reconstruction were evaluated in a cadaveric model for the posterior cruciate ligament [2].
- Septic arthritis after arthroscopic posterior cruciate ligament and multi-ligament reconstructions is rare [4].
- Septic arthritis after arthroscopic posterior cruciate ligament and multi-ligament reconstructions can be successfully treated with arthroscopic irrigation and debridement [4].
References¶
[1] Aaos Comprehensive Orthopaedic Review 3. Ligamentous Injuries of the Knee > II. Posterior Cruciate Ligament Injuries.
[2] Campbell S Operative Orthopaedics 4 Volume Set. ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION WITH BONE-PATELLAR TENDON-BONE GRAFT > POSTERIOR CRUCIATE LIGAMENT.
[3] A Lange Medical Book Current Diagnosis Treatment In Orthopedics Fifth Edition. 3Sports Medicine > 4. Posterior Cruciate Ligament Injuries.
[4] Campbell S Operative Orthopaedics 4 Volume Set. ANTERIOR CRUCIATE AND ANTROLATERAL LIGAMENT RECONSTRUCTION (BOX 51.8) > POSTERIOR CRUCIATE LIGAMENT.
[6] Orthopaedic Knowledge Update Sports Medicine 6. Cruciate Ligament Injuries > Posterior Cruciate Ligament Injury > Anatomy and Biomechanics.
[7] Campbell S Operative Orthopaedics 4 Volume Set. ANTERIOR CRUCIATE LIGAMENT RECONSTRUCTION WITH BONE-PATELLAR TENDON-BONE GRAFT > POSTERIOR CRUCIATE LIGAMENT ANATOMY.
[9] Tachdjian S Pediatric Orthopaedics From The Texas Scottish Rite Hospital For Children E Book. Plate 35.2 Scapulocostal Stabilization for Scapular Winging (Ketenjian Technique) > Pediatric Posterior Cruciate Ligament Injuries.
[14] Orthopaedic Knowledge Update Sports Medicine 6. Cruciate Ligament Injuries > Posterior Cruciate Ligament Injury > Diagnosis.
[17] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Soft-Tissue Injuries About the Knee > Posterior Cruciate Ligament > Treatment.
[18] Campbell S Operative Orthopaedics 4 Volume Set. ANTERIOR CRUCIATE AND ANTROLATERAL LIGAMENT RECONSTRUCTION (BOX 51.8) > POSTERIOR CRUCIATE LIGAMENT RECONSTRUCTION.
[19] Orthopaedic Knowledge Update Sports Medicine 6. Cruciate Ligament Injuries > Posterior Cruciate Ligament Injury > Treatment and Outcomes.
