Purpose: To evaluate the safety and efficacy of the novel iBalance Medial Opening Wedge High Tibial Osteotomy (HTO) system in executing lower limb realignment in patients with symptomatic varus gonarthrosis.
Methods: A multicentre case series of iBalance medial opening wedge HTO was compared to an historic case-matched control series of HTO's performed using another implant. Subjects were prospectively observed at 3, 6 and 12 months after surgery. Primary endpoints included the reporting of adverse events, weight-bearing status without pain and radiographic evidence of bony union. Secondary endpoints included maintenance of osteotomy correction angle, patient reported outcome (KOOS and SF-36) and gait analysis.
Results: Thirty-two consecutive patients were included in the iBalance group (mean age 49.7, 30-67; M:F, 20:12), paired with 32 control subjects (49.8, 35-66; 21:11). Three patients (9.4%) in the iBalance group experienced a complication requiring intervention versus one patient (3.1%) in the control group. No statistically significant differences were seen between groups in terms of time to weight bearing, radiographic union, implant stability or patient reported outcome. Gait analysis revealed a statistically significant reduction in knee external adduction moment (P < 0.001).
Conclusions: The iBalance medial opening wedge HTO system has been shown to be a safe, novel implant for use in proximal tibial osteotomy. This study shows that the iBalance medial opening wedge HTO system has an equivalent short-term safety and efficacy profile to the 2nd generation Puddu system.