Medial compartment Osteoarthritis is an age related chronic disturbance of weight distribution over the articular surface of the knee joint. The compensatory Varus deformity which develops leads to “bowing” of the legs. Traditionally, treatment involved conservative regimen of analgesics, physiotherapy and lifestyle modifications. Before the advent of Arthroplasty, Osteotomies were the mode the treatment. The treatment modality is divided into two phases. The first phase involves in correcting the mechanical axis deviation, through a high Tibial Osteotomy. The second phase involves stabilizing this accomplishment with an Ilizarov external fixator and achieving the co-linearity of the Mechanical axis of the lower extremity through angular correction using distraction Osteosynthesis.
Aim: The aim of present study was to evaluate the results of High Tibial osteotomy using Ilizarov technique in medial compartment osteoarthritis of the knee.
Materials and Methods: In this prospective study, thirty cases of medial compartment osteoarthritis of the Knee with genu Varus deformity were treated using monofocal corticotomy and ring fixator. Bone and functional results were evaluated clinically using the Knee Society score (knee score and functional score) and radiologically using the mechanical tibiofemoral angle and the Mechanical axis deviation from the Fujisawa point.
Results and Discussion: In the present series of thirty cases, there were 20 females and 2 males with a maximum age of 52 years and minimum of 32 years. There was a predominance of Varus deformity seen on the right knee. The mean follow up was 30 months. The results observed were 60% excellent, 33% fair and 6.7% poor by knee society score. The mean knee society score (Knee score) at 12 months was 71.27 ± 5.32 (p<0.001) and at 24 months was 78± 6.42(p<0.001). The mean Tibio femoral angle was 3.40 ± 1.07º of valgus (p˂0.001) at 12 months postoperatively and at 24 months was 3.7 ± 1.35º of valgus (p˂0.001). The mean Mechanical axis deviation from Fujisawa point was 0.76± 0.42 millimetres (p˂0.001) at 12 months postoperatively and 0.75 ± 0.45 millimetres (p˂0.001) at 24 months postoperatively. The correlation between Knee society score and the Tibiofemoral angle was significant at 12 months (r= 0.368) compared to the correlation between Knee society score and the deviation from Fujisawa point which was non significant at 12 months(r= -0.340) and was significant at the end of 24 months (r= -0.552).At the end of 24 months, 93.7% of the cases showed excellent to good results after the intervention and only 6.7% of the cases showed poor result.
Conclusion: In the light of these results, it was concluded that high Tibial osteotomy by Ilizarov technique, despite few unfavourable results and complications, can be used to treat angular deformity correction about the knee.