To evaluate the functional results, activity status after surgical treatment in combined PCL and PL instability of the knee.

Fifteen patients with combined PCL and PL injury were diagnosed and treated. PCL injury was treated by using tibial inlay method with arthroscopy and PL injury was treated by using repair (acute 4 cases) and reconstruction (chronic 11 cases, Warren method) and followed more than 2 years with average follow-up period of 27.3 months (24-38). Mean age was 39 years (17-67) at operation. Radiologic evaluation was done by simple X-ray, stress view and MRI. Functional evaluation of Lysholm score and Tegner activity score was used.

Average Lysholm and Tegner activity score was 43 and 1.5 preoperatively and was improved to 85 and 4.0 postoperatively. Varus laxity was improved from 9.3 mm to 4.0 mm and posterior translation was improved from 18.4 mm to 5.6 mm in stress view. The PCL and PL instability of the knee were improved in all cases. Postoperative improvement of functional and activity score were determined by absence of combined injury not by age or delayed time for operation. Complications were limitation of motion (3 cases), lateral instability (4 cases), osteoarthritic change (4 cases) and quadriceps atrophy (15 cases, severe 4 cases).

PCL reconstruction using tibial inlay method and PL reconstruction using warren method (chronic cases) and repair (acute cases) improved function, activity and stability in PCL and posterolateral instability.