Ang iyong nararamdaman¶
Ang pinsala sa posterior cruciate ligament ay nangyayari kapag ang ligament sa likod ng iyong tuhod ay naunat o napunit. Karaniwan itong sanhi ng impact sa harap ng iyong shin, gaya ng pagtama ng iyong tuhod sa dashboard ng kotse, o pagkahulog sa isang nakabaluktot na tuhod habang ang iyong mga daliri sa paa ay nakaturo pababa. Ang mga sports injury sa ligament na ito ay nagmumula sa direktang tama o panlabas na puwersa, hindi mula sa mga pag-ikot at pagbagal na paggalaw na nakapipinsala sa ibang mga ligament ng tuhod.
Karamihan sa mga taong may ganitong pinsala ay nakararamdam ng sakit, pamamaga, at paninigas sa tuhod. Hindi tulad ng ibang pinsala sa ligament ng tuhod, maaaring wala kang narinig na "pop" sa oras ng pangyayari, at maaaring hindi mo maramdamang unstable ang iyong tuhod kahit kaunti. Ang sakit ay madalas na nasa harap ng tuhod sa paligid ng kneecap, o sa inner side o likod ng tuhod. Karaniwan itong lumalabas kapag naglalakad ka paakyat o pababa ng burol. Ang mga pang-araw-araw na gawain na nagbibigay ng load sa harap ng tuhod, gaya ng pag-akyat at pagbaba ng hagdan o pagbangon mula sa isang mababang upuan, ay maaaring maging hindi komportable. Ang ilang tao ay nakapapansin ng pagdurugo sa loob ng joint agad pagkatapos ng pinsala, na nagiging sanhi ng pamamaga at pakiramdam na masikip ang tuhod.
Kung ang iyong pinsala ay matagal na o may kasamang ibang bahagi ng tuhod, maaaring magbago ang sitwasyon. Ang ilang tao ay halos walang nararamdaman, habang ang iba naman ay nararamdamang bumibigay ang tuhod, lalo na kung ang outer side ng tuhod ay napinsala rin o kung ang iyong mga binti ay natural na bowed outwards. Sa paglipas ng panahon, ang kneecap joint at ang inner part ng tuhod ay maaaring magkaroon ng wear-and-tear arthritis, kaya mahalaga ang patuloy na sakit sa mga bahaging iyon.
Ano ang aktwal na nangyayari¶
Sa loob ng iyong tuhod, may dalawang matitibay na tali na nagkakrus sa gitna ng joint. Ang nasa likod ay tinatawag na posterior cruciate ligament, o PCL. Isipin ito bilang isang makapal na lubid na pumipigil sa iyong shin bone (buto sa binti) na dumulas pabalik sa ilalim ng iyong thigh bone (buto sa hita). Gumagana ito sa bawat anggulo ng tuhod, nakatuwid man o nakabaluktot, at tumutulong din itong panatilihing matatag ang tuhod laban sa mga puwersang patagilid at pag-ikot.
Ang PCL ay binubuo talaga ng dalawang bahagi na nagtutulungan. Ang isang bahagi ay humihigpit kapag nakabaluktot ang iyong tuhod, at ang isa naman ay humihigpit kapag nakatuwid ang iyong tuhod. Kapag ang ligament ay na-stretch o napunit, ang isa o parehong bahaging ito ay hindi na nakakagawa ng kanilang tungkulin, kaya ang shin bone ay maaaring gumalaw pabalik nang higit sa dapat. Ang kaluwagang iyon, kasama ang dagdag na load na ibinibigay nito sa harap at panloob na bahagi ng tuhod, ang nagdudulot ng sakit at paninigas na nabasa mo sa itaas.
Inilalarawan ng mga doktor kung gaano kalala ang pinsala sa ligament sa pamamagitan ng grading. Ang mild grade ay nangangahulugang ang ligament ay na-stretch ngunit konektado pa rin, tulad ng isang lubid na may ilang himaymay na naputol. Ang middle grade ay nangangahulugang ito ay bahagyang napunit at mas maluwag kaysa sa normal. Ang severe grade ay nangangahulugang ang ligament ay napunit nang tuluyan, kaya hindi na nito nahahawakan ang shin bone sa tamang posisyon. Ang mga mild at moderate na pinsala ay madalas na gumagaling nang walang surgery, lalo na kung maayos ang ibang bahagi ng tuhod. Ang isang complete tear, o iyong may kasamang pinsala sa ibang mga ligament o sa outer corner ng tuhod, ay mas malamang na mangailangan ng operasyon.
Mahalagang malaman na ang ligament na ito ay mas makapal at mas matibay kaysa sa mas kilalang ligament sa harap ng tuhod, kaya ang pagkapinsala nito ay karaniwang nangangailangan ng malakas na puwersa. Iyon din ang dahilan kung bakit ang mga pinsalang ito ay madalas na may kasamang pinsala sa ibang bahagi ng tuhod, at kung bakit susuriing mabuti ng iyong surgeon ang buong joint bago magpasya kung anong gamutan ang kailangan mo.
Ano ang maaari naming gawin tungkol dito¶
Karamihan sa mga mild at moderate na pinsala ay gumagaling nang walang operasyon. Nagsisimula kami sa physiotherapy na nagpapalakas sa kalamnan ng hita sa harap ng iyong binti, na tinatawag na quadriceps. Ang kalamnang iyon ang humahawak sa iyong shin bone pasulong at pinipigilan itong lumundo pabalik, na siyang pangunahing problema kapag maluwag ang ligament na ito. Ang isang espesyal na brace ay maaari ring makatulong sa pagpapanatili ng buto sa tamang posisyon. Para sa mild o moderate na pinsala, karamihan sa mga tao ay nakakabalik sa sports sa loob ng 2 hanggang 4 na linggo. Ang isang complete tear na ginamot nang walang surgery ay karaniwang nangangahulugan ng pagpapanatiling diretso ng tuhod sa isang brace o cast sa loob ng 4 na linggo, bago lumipat sa strengthening work. Sa tuloy-tuloy na quadriceps exercises, 80% ng mga pinsalang ito ay nakakamit ang magandang resulta nang walang surgery.
Nagiging opsyon ang surgery kapag ang ligament ay napunit nang tuluyan at ang iyong tuhod ay nananatiling masakit o unstable, o kapag may iba pang mga ligament na napinsala sa parehong pagkakataon. Kung maraming ligament ang napunit, karaniwan naming inirerekomenda ang maagang operasyon kaysa maghintay. Pinapalitan ng operasyon ang napunit na ligament ng isang bagong piraso ng tissue, na tinatawag na graft, upang ang shin bone ay mahawakan muli sa tamang posisyon. Kung may piraso ng buto na nahila kasama ng ligament, maaari itong ibalik at i-fix sa posisyon nito. Pag-uusapan namin ang mga detalye ng operasyon sa sarili nitong pahina, at magdedesisyon ka kasama namin kung ito ang tama para sa iyo.
Ano ang dapat asahan¶
Para sa banayad o katamtamang pinsala, ang outlook ay madalas na stable. Sa pamamagitan ng mga strengthening exercise at, kung kinakailangan, isang brace, ang sakit at pamamaga ay karaniwang humuhupa sa loob ng ilang linggo sa halip na mga buwan, at maraming tao ang mabilis na nakakabalik sa sports. Ang mga long-term result nang walang operasyon ay nagpapakita na ang mga tao ay nananatiling aktibo, na may mabuting lakas at full range of motion sa tuhod. Kahit na may natitirang kaunting looseness, hindi ito laging nagdudulot ng problema. Ang ilang mga tao na may lasting looseness ay nag-uulat na wala silang anumang functional difficulties.
Ang complete tear ay ibang usapan. Kung hahayaan, ang isang fully torn ligament ay hindi kusang nagdidikit muli, at ang looseness ay may tendensiyang manatili. Sa paglipas ng mga taon, ang sobrang paggalaw na iyon ay maaaring magbigay ng load sa harap at panloob na bahagi ng tuhod at humantong sa wear-and-tear arthritis, kaya mahalaga ang patuloy na sakit doon. Sa mga bata, ang masyadong matagal na paghihintay bago operahan ay nagpapataas ng panganib ng pinsala sa cushioning cartilage sa tuhod, na maaaring humantong sa mahinang long-term outcomes.
Kung kailangan mo ng operasyon, mahalagang malaman kung ano ang kaya at hindi kayang ayusin nito. Ang pagpapalit ng ligament ay nagpapabuti sa pakiramdam ng iyong tuhod at ginagawang mas posible ang pagbabalik sa sports. Sa mga pinsala kung saan maraming ligament ang napunit, lahat ng pasyente ay may stable na ligament sa kanilang pinakabagong check-up, at 77% ay walang looseness kahit kaunti. Para sa isang complete tear lamang, ang mga resulta ay mabuti ngunit hindi perpekto: ang ligament ay fully stable muli sa halos kalahati ng mga tuhod, habang ang iba ay nananatiling may mild o moderate looseness. Ang mga combined injuries na kinasasangkutan ng outer corner ng tuhod ay may tendensiyang hindi gaanong gumaling kumpara sa mga pinsala sa iisang ligament, at ang mga resulta sa pangkalahatan ay hindi nakakaabot sa antas na nakikita pagkatapos ng mga front-of-knee ligament repair. Sa loob ng unang 2 taon pagkatapos ng operasyon, ang failure rates ay magkakatulad kahit isa o ilang ligament ang muling binuo. Karamihan sa mga tao ay napananatili ang natural na sense ng kung nasaan ang kanilang tuhod sa space, at ang knee scores at looseness ay parehong bumubuti pagkatapos ng operasyon.
Kailan dapat magpatingin¶
Magpatingin sa iyong GP kung mayroon kang pananakit, pamamaga, o paninigas ng tuhod pagkatapos ng isang impact sa harap ng iyong shin o pagkahulog nang nakabaluktot ang tuhod, lalo na kung mabilis na namamaga ang tuhod at pakiramdam ay banat dahil sa pagdurugo sa loob ng joint. Humingi ng review mula sa isang espesyalista kung ang pananakit sa harap, panloob na bahagi, o likod ng tuhod ay patuloy na nagbibigay-abala sa iyo sa mga ahon o hagdan, o kung ang iyong tuhod ay nagsisimulang lumuwag o bumibigay, na mas malamang na mangyari kapag ang ibang bahagi ng tuhod ay napinsala rin. Pumunta agad sa emergency department kung ang iyong tuhod ay na-dislocate o kung ilang ligaments ang napunit sa isang pagkahulog o crash, dahil ang mga blood vessel at nerve sa likod ng tuhod ay maaaring mapinsala at kailangang masuri sa mismong araw na iyon. Kung naoperahan na ang ligament na ito at ang tuhod ay naging mainit, mapula, namamaga, at nilalagnat, kailangan din nito ng urgent assessment.
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.
