Posterior Cruciate Liagment (PCL)
Grade III (severe) The PCL is either completely torn or is separated at its end from the bone that it normally anchors, and the knee is more unstabile. Because it usually takes a large amount of force to cause a severe PCL injury, patients with Grade III PCL sprains often also have sprains of the ACL or collateral ligaments or other significant knee injuries.
A variety of graft choices are available to surgeons that include autogenous patellar or quadriceps tendon with bone blocks, or hamstring tendons. In addition, patellar tendon or achilles tendon allografts (from donors) may be used. The main portion of the PCL which needs to be reconstructed is the anterolateral bundles. Arthroscopic assisted or open PCL reconstructions involve removing the remaining native PCL, with care to preserve the ligament of Wrisberg if it is intact. A tunnel is drilled at the anatomic attachment site of the anterolateral bundle at the anteromedial wall of the itercondylar notch, in line with the roof of the notch and about 6-8 mm from the articular surface of the medial femoral condyle. The tibial attachment site is then prepared by identifying the normal attachment site of the PCL at the bottom of the PCL facet. A tibial tunnel is then drilled, at approximately a 75º angle and about 6 cm from the joint line, from anteriorly to posteriorly. Once the tunnels are drilled, sharp edges and soft tissues around the tunnel exit site are smoothed off with the use of a rasp. The graft is then passed into the joint and fixed in its femoral tunnel (usually with a cannulated interference screw). The graft is then tensioned distally while the knee is cycled several times to remove any slack in the graft. The graft is then fixed to the tibia, usually with staples, while the knee is flexed to 90º, distal traction is placed on the graft, and an anterior force is applied to the tibia. After fixation, the posterior drawer is assessed to verify a return of normal posterior stability to the knee, and the surgical incisions are closed.
Postoperatively, it is recommended that the patient remain in full extension for a period of 2 to 4 weeks for isolated PCL reconstructions. In multiligament reconstructions, the patient is often placed into a continuous passive motion (CPM) machine for range of motion. Patients are non weight bearing with quad sets and straight leg raises in the immobilizer only started the 1st postoperative day. It is especially important for PCL reconstruction patients to not have any posterior sag of their tibia which would stretch out the graft. Pillows or other support under the tibia is required for the first two months after surgery. After 8 weeks, weight bearing is initiated and more active rehabilitation is started.