Efficacy of Tibial Proximal Osteotomy in Correction of Lower Limb Alignment Indexes in Patients with Osteoarthritis in Medial Compartment of Knee

Abstract

I ntroduction: Tibial proximal osteotomy is one of the treatments for patients with knee compartment osteoarthritis. Studies showed 80 % good prognosis in five years follow up after osteotomy. Almost always this method is used for pure medial knee compartment osteoarthritis that has a varus deformity. The aim of all methods is reforming varus deformity and lower limb alignment to gain 3 to 5 degree extra reformation and take knee in 10 degree valgus. One of the main etiologies for patients inconvenience and no decreasing in their pain is overcorrection or undercorrection, but unfortunately these can't be noticed. Therefore we must make sure that additional stress on the medial joint line was eliminated and regeneration of cartilage was facilitated or at least occurrence of osteochondritis was decreased. So we aimed to determine the efficacy of tibial proximal osteotomy in lower limb alignment indexes in patients with osteoarthritis in medial compartment of knee. Material and methods: This study is a clinical trial study that has done in Alzahra University Hospital of Isfahan Medical Science University in Iran since June 2010 till February in 2011. Patients had pain, pure medial knee compartment osteoarthritis and varus deformities were determined for study. Patients who wouldn't come for control, those who had no convenience for giving their data or osteoarthritis of all three compartments were excluded from study. Number of patients has determined 40 persons according to previous studies. Sampling occurred convenient. Before any surgical processes, the AP x-ray radiography was applied for alignment view. The demographic and radiographic data was registered. Six months later we applied AP x-ray radiography again and obtained data and analysis them with SPSS software and T-Paired statistical method. Results: The mean of anatomical limb angle before and after surgical process were 5.1 ± 3.4 varus and 11.9 ± 3.4 degree valgus , respectively ,so with T-test there was a significant difference between them (P<0.001).The mean of mechanical limb angle before and after surgical process were 12.6 ± 3.4 varus and 4.75±3.5 degree valgus, respectively. Therefor with T-test, there was significant difference between them (P<0.001). Conclusion: Results were achieved from this study showed that Tibial proximal osteotomy is appropriate treatment for young and middle age patients with progressive deformity, symptomatic varus knee.