Biplanar Open-Wedge High Tibial Osteotomy with Locking Plate for Treatment of Osteoarthritic Varus Knee

Abstract

Aim: To introduce and characterize the modified biplanar opening high tibial osteotomy with rigid fixation to treat unicompartmental knee arthritis with varus deformity in active lifestyle patients. Patients and Method: 48 patients (19 females) with monocompartmental gonarthrosis of the knee combined with varus malalignment, 41 with bilateral affection and 7 cases with unilateral gonarthritis (total 89 knees). Mean age: 53 years (range from 42 to 61 years). They were treated and followed from June 2010 to May 2014 (35 months). Biplanar opening high tibial osteotomy technique was used and fixed by low profile locked T-plate (21 cases) and low profile anatomical proximal tibial plate (27cases). Pre-operative mean varus deformity was 16.5° (9° - 19°). We utilized Lysholm score and Knee Society Score for evaluation of preoperative and follow-up data. Results: The average correction angle was 11.50 ± 2.50° (7° - 19°). Preoperative posterior tibial slope was 8.04° ± 1.30° and at last follow-up 9.15° ± 1.60°, respectively (p = 0.437). The joint space distance increased from 4.05 ± 1.30 mm to 4.83 ± 1.33 mm (p < 0.001). The average time to complete bone union was 14.69 ± 1.5 weeks. There were no cases of delayed union or non-union. No major complications like broken plate, nerve injury, or blood vessel injury occurred. No progression of degenerations developed in the three compartments of the knee at final follow-up. The mean score on the Lysholm-Gillquist knee functional scoring scale was 45.5 ± 21.7 preoperatively, and it improved to 77.0 ± 23.9 (p < 0.001). There was no obvious difference in the range of motion before and after operation. The average knee score improved from 51.19 ± 11.82 to 93.49 ± 5.10. Conclusion: Biplanar opening high tibial osteotomy fixed with locking compression plate gives good results for symptomatic unicompartmental gonarthrosis with genu varum. Also this technique can be applied for medial compartment degeneration of the knee without deformity with good functional outcomes.