The MidTerm Outcome of Total Knee Arthroplasty in Patients With Prior High Tibial Osteotomy: A Prospective Study

Background It is generally accepted that total knee arthroplasty (TKA) after high tibial osteotomy (HTO) is technically more difficult; however, there is still disagreement whether the subsequent arthroplasty is compromised. Objectives The current case series study aimed to assess patients treated by knee arthroplasty after a previous high tibial osteotomy and to determine the influence of this osteotomy on the clinical and radiologic outcomes of subsequent arthroplasty. Methods Up to April 2013, twentythree patients with a history of twentyfive proximal tibial osteotomies prior to TKA were identified and compared with a matched group who underwent primary TKA in Shafa Orthopedic Hospital, Tehran, Iran. Demographic parameters of patients, surgical details, the knee range of motion (ROM), and American functional knee society (AKS) scores before and after TKA were recorded in the HTO and control groups. Weight bearing alignment radiographs were taken preoperatively and at the last followup. At the latest visit, patients’ satisfaction was recorded. Results After an average of 49 months followup, all patients in the HTO and control groups were satisfied with their current level of function. In the HTO group, the rectus snip had to be used for better exposure in eight cases. There was no statistically significant difference between the two groups in postoperative knee ROM, mechanical leg alignment and mean functional knee society score, but the mean of operation time in the HTO group was significantly longer than that of the TKA time in the control group. Conclusion Although knee arthroplasty after HTO is technically more challenging than a primary procedure, the results of clinical scores, postoperative ROM and radiological evaluation in the study subjects were comparable with those of the primary TKA in midterm followup. Rectus snip is a safe procedure in such difficult cases for better exposure.