Tibial Tubercle Osteotomy for Patellar Chondral Pathology in an Active United States Military Population

Abstract

To quantify rates of perioperative complications, secondary surgery, subjective pain relief, and knee-related medical separation in an active military population after a tibial tubercle osteotomy (TTO) for the primary indication of chondral pathology. All active-duty service members undergoing TTO with a minimum of 2years' follow-up were isolated from the Military Health System database. The exclusion criteria were patients with patellar instability, other periarticular osteotomy, and insufficient follow-up. Demographic information and surgical characteristics were abstracted from the electronic health record and correlated with improvement in pain and medical discharge from the military. A total of 76 patients (86 knees) who underwent TTO for patellofemoral chondromalacia were identified with a mean age of 32.3years. Major and minor complications occurred in four patients (4.7%) and three patients (3.5%), respectively, and the overall improvement in the visual analog scale score after TTO was 1.5 (P < .0001). At a mean follow-up of 3.4years (range, 2.0 to 7.3years), 37% of patients were unable to return to modified military activity because of knee-related limitations. Junior military rank group (P= .0084), age younger than 35years (P= .0031), bilateral TTO procedures (P= .0294), and tobacco use (P= .0218; odds ratio, 3.29; 95% confidence interval, 1.19 to 9.12) were risk factors for medical separation, whereas absence of concomitant chondral repair (P= .5408), previous knee procedures (P= .9674), and greater occupational demands (P= .7062) were not. At short-term to midterm follow-up, 63% of patients successfully returned to military function with a low rate of perioperative complications (8%). The postoperative decrease in pain after TTO is of unknown clinical significance. Age younger than 35years, junior military rank, bilateral TTO procedures, and tobacco use were significant risk factors for medical separation, whereas absence of concomitant cartilage repair, previous knee procedures, and lower occupational demands were not associated with improved visual analog scale scores or prevention of knee-related medical discharge. Level IV, therapeutic case series.