Total knee arthroplasty for profound varus deformity: technique and radiological results in 173 knees with varus of more than 20 degrees.

Abstract

One hundred seventy-three knees in 117 patients with varus deformity exceeding 20 degrees were prospectively evaluated. Using selective posteromedial release, reduction osteotomy of posteromedial tibial flare, and extra-articular tibial osteotomy, with the preservation of medial collateral ligament integrity, mean tibiofemoral angle of 22.7 degrees varus preoperatively (range, 15 degrees-62 degrees) was corrected to 5.3 degrees valgus (range, 2 degrees-9 degrees) postoperatively. Eighty-six percent of the knees were in 4 degrees to 10 degrees valgus postoperatively. Mean Knee Society score improved from 22.8 (range, 0-64) to 91.1 (range, 52-99), and function score from 22.8 (range, 0-64) to 72.1 (range, 5-100) at 2.6 years (range, 2-9 years). Mean femoral component valgus was 95.5 degrees (range, 92 degrees-98 degrees), and mean tibial component valgus was 89.8 degrees (range, 86 degrees-94 degrees). Of 30 grafts for posteromedial tibial defects, 28 were successfully incorporated. No patient reported significant instability. Three knees (1.7%) showed tibial component loosening with recurrence of deformity. Correction of severe varus deformity by the technique reported can successfully restore alignment, pain-free motion, and stability.