Posterolateral dislocation of the knee joints:analysis of 9 cases

Objective: To analyze the traumatic pathological characteristics of posterolateral dislocation of knee joints and its treatment.Methods: Nine cases of posterolateral dislocation of knee joint ,5 cases of fresh injuries (the fresh injury group) and 4 cases of old injuries ( the old injury group) were reviewed and analyzed. In the fresh injury group 4 cases failed in close reduction due to "buttonholing" through the medial jo int,among them 3 cases underwent repair of the damaged ligaments. In the old in jury group 2 cases underwent ACL and MCL repair only in acute stage,but re-dis located. Of the rest 2 cases 1 was associated with peroneal nerve injury and the other was not treated in acute stage. One case was associated with comminuted f racture of the tibial condyle and popliteal artery injury. Open reduction was pe rformed in 3 cases. One case was fixed with 2-crossed pin and another was fixe d with one pin through the tibial and femoral condyle and second pin with olecra nization fixation. Plaster immobilization for 6-8 weeks respectively was requir ed. In the old injury group in 1 case ACL and PCL repair (Augustine method) and posterolateral structure were performed and olecranization fixation and plaster immobilization for 6 weeks was needed. Arthrodesis of the knee was done for the patient with comminuted fracture of the tibial condyle and popliteal artery inj ury. Results: All the cases were followed up for 1-23 years (averag e 6 years). Knee stability in 4 cases with repair of the ligaments was improved,although PDT showed (+) with different degrees. The results of the patients tre ated with ligamentous reconstruction were much better than those of the patients without any repair. Conclusions: Well understanding of the traumatic pathological c haracteristics,repair of the damaged ligaments,augmentation of olecranization fixation and postoperative immobilization for 6 weeks are the key points of succ essful treatment.