Primary knee osteoarthritis (OA) is one of the degenerative diseases that destroy auricular cartilage within knee joint and cause pain, varies deformity, decrease knee function. Total knee arthroplasty (TKA) is an effective intervention in order to relieve pain, improve function and QOL (quality of life) in patients with severe osteoarthritis of the knees that have different degrees of varus deformity. However, we are not aware of any study to shows if medial side defect in tibia has any association with outcome. We conceive this study of finding out if medial side defect of tibia affects the outcome. 124 patients (143 knees) with primary knee OA with different stages of defects participated in this study. Patients classified into two groups based on Rand classification of knee defects (patients with Rand I and II in group 1 and patients with Rand III and IV in group 2). Pain and knee alignment have been measured by Visual analog scale (VAS) and 3-joint X-ray and quality of life, knee function and radiographic have been measured by questionnaires of SF 36, WOMAC and KSS score. The mean follow-up was 18. 2 mounts (range 12 to 23 months). The results showed that all of the parameters improved significantly within groups (P≤0.001). Comparison TKA between two groups in the postoperative analysis shows that there was a significant difference between groups in pain, radiographic and functional KSS and WOMAC score (P≤0.05). So group 1 had better results in these parameters than group 2 after surgery. TKA is an effective intervention for all patients with severe osteoarthritis and varus deformity. However, the severity of medial tibial defects is an important determinant of outcome. Patients with a more severe deformity have less favorable outcome.
Keywords: Medial tibial defect; Osteoarthritis; Pain; Quality of life; Total knee arthroplasty; Varus deformity.