Summary PCL injuries are traumatic knee injuries that may lead to posterior knee instability and often present in combination with other ipsilateral ligamentous knee injuries (i.e PLC, ACL). Diagnosis can be suspected clinically with a traumatic knee effusion and increased laxity on a posterior drawer test but requires an MRI for confirmation. Treatment can be nonoperative or operative depending on the severity of injury to the PCL, as well concomitant injuries to surrounding structures and ligaments in the knee. Epidemiology Incidence 5-20% of all knee ligamentous injuries Etiology Pathophysiology mechanism login to view 3 more bullets pathoanatomy login to view 3 more bullets Associated conditions combined PCL and posterolateral corner (PLC) injuries multiligamentous knee injuries knee dislocation Anatomy PCL anatomy origin login to view 2 more bullets insertion login to view 1 more bullet dimensions login to view 2 more bullets PCL has two bundles login to view 7 more bullets lies between the meniscofemoral ligaments login to view 2 more bullets Blood supply supplied by branches of the middle geniculate artery and fat pad Biomechanics strength is 2500 to 3000 N (posterior) minimizes posterior tibial displacement (95%) Classification PCL injury classification (based on posterior subluxation of tibia relative to femoral condyles with knee in 90° of flexion) Grade I a partial tear exam shows 1-5 mm posterior tibial translation Tibia remains anterior to the femoral condyles Grade II a complete isolate tear exam shows 6-10 mm posterior tibial translation complete injury in which the anterior tibia is flush with the femoral condyles Grade III a combined PCL + capsuloligamentous injury exam shows >10mm posterior tibial translation tibia is posterior to the femoral condyles and often indicates an associated ACL and/or PLC injury Presentation History differentiate between high- and low-energy trauma login to view 2 more bullets ascertain a history of dislocation or neurologic injury Symptoms posterior knee pain instability login to view 1 more bullet Physical exam varus/valgus stress login to view 2 more bullets posterior sag sign login to view 3 more bullets posterior drawer test (at 90° flexion) login to view 4 more bullets quadriceps active test login to view 2 more bullets dial test login to view 2 more bullets KT-1000 and KT-2000 knee ligament arthrometers login to view 1 more bullet Imaging Radiographs recommended views login to view 10 more bullets MRI confirmatory study for the diagnosis of PCL injury Treatment Nonoperative protected weight bearing & rehab login to view 6 more bullets relative immobilization in extension for 4 weeks login to view 6 more bullets Operative PCL repair of bony avulsion fractures or reconstruction login to view 20 more bullets high tibial osteotomy login to view 6 more bullets Surgical Techniques Arthroscopic transtibial technique approach login to view 4 more bullets technique login to view 3 more bullets pros & cons login to view 1 more bullet Open (tibial inlay) approach login to view 1 more bullet technique login to view 1 more bullet pros & cons login to view 2 more bullets Single-bundle technique approach login to view 1 more bullet technique login to view 2 more bullets Double-bundle technique approach login to view 1 more bullet technique login to view 2 more bullets pros & cons login to view 3 more bullets Rehabilitation Postoperative care immobilize in extension early and protect against gravity early motion should be in prone position Rehabilitation focus on quadriceps rehabilitation avoid resisted hamstring strengthening exercises (ex. hamstring curls) in early rehab login to view 1 more bullet Complications Popliteal artery injury at risk when drilling the tibial tunnel (increases with knee extension) lies just posterior to PCL insertion on the tibia, separated only by posterior capsule Patellofemoral and medial sided pain/arthritis due to chronic PCL deficiency Prognosis Chronic PCL deficiency PCL deficiency leads to increased contact pressures in the patellofemoral and medial compartments of the knee due to varus alignment controversial whether late patellar and MFC chondrosis will develop