Auxiliary medial small locking plate fixation enhances bone healing and minimizes delayed union in inverted V-shaped high tibial osteotomy: A comparative study of 154 knees.

PURPOSE: To determine whether auxiliary fixation with a T-shaped small locking plate (SLP) placed on the medial tibial cortex can enhance bone healing and reduce delayed union compared with the conventional inverted V-shaped high tibial osteotomy (iVHTO) fixed with a locking compression plate (LCP).

METHODS

This retrospective cohort study included 154 knees (135 patients) that underwent iVHTO. The knees were allocated to Group S (n = 72), treated with conventional single LCP fixation, and Group D (n = 82), treated with auxiliary medial SLP fixation in addition to the conventional procedure. Radiological and clinical evaluations were performed with a minimum follow-up of 2 years. Bone healing was assessed using radiographs and computed tomography scans, and the time to complete union was quantitatively evaluated with an established scoring system.

RESULTS

The time to union was significantly shorter in Group D than in Group S (median, 8 vs. 12 weeks; p < 0.001; 95% confidence interval [CI] for the difference, 0.0-4.0 weeks). The incidences of delayed union and non-union were both significantly lower in Group D than in Group S (2.4% vs. 20.8% and 0% vs. 5.6%, respectively; p < 0.001 and p = 0.046; 95% CIs, 8.6%-29.3% and 0.0%-13.4%). The rate of other complications, including transient anterior compartment syndrome and superficial infection, did not differ significantly between the groups (4.9% vs. 4.2%; p = 0.98; 95% CI, -7.2% to 8.2%). The Lysholm score was slightly but significantly higher in Group D than in Group S (p = 0.043; 95% CI, 0.0-5.0), whereas no significant differences were observed in the other clinical scores.

CONCLUSION

Auxiliary medial fixation using an SLP enhanced bone healing and minimized the incidence of delayed union or non-union following conventional iVHTO with single lateral LCP fixation, without increasing other complications or compromising clinical outcomes.

LEVEL OF EVIDENCE: Level III, prospective cohort study.