Treatment of posterior cruciate ligament injuries and knee dislocations

The combined anterior and posterior cruciate ligament (ACL PCL) injured (dislocated) knee is a severe injury that can result from high or low energy trauma. Both cruciates are torn plus one or both collateral ligament complexes. The frequency of popliteal artery injuries occurs with the same frequency in bicruciate knee ligament injuries, and frank tibio-femoral dislocations. Nerve injuries, associated fractures, functional instability, and post traumatic arthrosis may all occur with this injury complex. Surgical treatment offers good functional results documented in the literature by physical examination, arthrometer testing, stress radiography, and knee ligament rating scales. Mechanical tensioning devices are helpful with cruciate ligament tensioning. Some low grade medial collateral ligament (MCL) complex injuries may be amenable to brace treatment, while high grade medial side injuries require repair-reconstruction. Lateral posterolateral injuries are most often successfully treated with surgical repair-reconstruction. Surgical timing in acute multiple ligament injured knee cases depends upon the ligaments injured, injured extremity vascular status, skin condition of the extremity, degree of instability, and the patients overall health. The author's preference is allograft tissue for these complex surgical procedures. Delayed reconstruction of 2 to 3 weeks may decrease the incidence of arthrofibrosis, and it is important to address all components of the instability. Currently, there is no conclusive evidence that double bundle PCL reconstruction provides superior results to single bundle PCL reconstruction in the multiple ligament injured knee.