Success of High Tibial Osteotomy in the United States Military

BACKGROUND: Historically, high tibial osteotomy (HTO) has been performed to treat isolated medial gonarthrosis with varus deformity. PURPOSE: To evaluate the occupational outcomes of HTO in a high-demand military cohort. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A retrospective analysis of active duty service members undergoing HTO for coronal plane malalignment and/or intra-articular pathology was performed using the Military Health System between 2003 and 2011. Demographic parameters and surgical variables, including rates of perioperative complications, secondary surgery, activity limitations, and medical discharge, were extracted from electronic medical records. For the current study, cumulative failure was defined as conversion to knee arthroplasty or postoperative medical discharge for persistent knee dysfunction. Univariate and multivariate analyses were performed to identify statistical associations with cumulative failure after HTO. RESULTS: A total of 181 service members (202 HTOs) were identified at an average follow-up of 47.5 months (range, 24-96 months). Mean age was 35.7 years (range, 19-55 years), and the majority were men (93%) and of enlisted rank (78%). All index procedures utilized a valgus-producing, opening wedge technique. Concomitant or staged procedures were performed in 87 patients (48%), including 40 ligamentous, 48 meniscal, and 48 chondral procedures. Complications occurred in 19.3% of knees (n = 39), with unplanned reoperation in 26 knees (12.8%). Fifty-three patients (40.7%) had minor activity limitations during military duty postoperatively. Eleven knees (5.4%) underwent conversion to total knee arthroplasty. The cumulative failure rate was 28.2% (n = 51) at 2- to 8-year follow-up. Patient age younger than 30 years at the time of surgery was associated with an independently higher risk of failure, whereas sex, concomitant/staged procedures, and perioperative complications were not significantly associated with subsequent failure. CONCLUSION: At short- to midterm follow-up, nearly 72% of all service members undergoing HTO returned to military duty and were free from conversion knee arthroplasty.