Correction of ligament and bone defects in total arthroplasty of the severely valgus knee.

One hundred thirty-five knees with valgus deformity were treated with a minimally constrained, cementless total knee replacement using intramedullary alignment for the femur and tibia. Mean valgus angle before surgery was 16 degrees; mean valgus angle after surgery was 7 degrees. Neither alignment nor varus-valgus stability deteriorated during the six-year follow-up period, but the knees with greater than 25 degrees deformity had a tendency to increase posterior laxity. Severely deformed knees required bone grafting of the medial femoral and tibial surfaces. A technique was developed to resect the distal femur measured from the medial femoral condyle and to maintain joint line position. Patellar subluxation and dislocation occurred in fewer than 1% of the cases. Despite the absence of rotational constraint at the articular surface, there was no tendency for patellar stability to deteriorate over time.