Factors Contributing to the Need for Non-Elective Explant following Surgical Repair of Tibial Tuberosity Avulsion Fracture.

Objective:  The aim of this study was to evaluate factors contributing to the need for non-elective explant following surgical repair of tibial tuberosity avulsion fractures.

Study Design:  Retrospective multicentre case-control study. Over a 5-year period, dogs ( = 63) that underwent surgical repair of tibial tuberosity avulsion fractures ( = 64) were considered. Dogs that underwent a non-elective explant were compared with those that did not. Continuous variables were compared with the Mann-Whitney U test. Categorical variables were compared with the Fisher's exact test. Variables which were significant on univariate analysis were entered into a multiple logistic regression model. Significance was set at  < 0.05.

Results:  Non-elective explant was performed in 20/64 fractures and elective explant was performed in 2/64 fractures. Neutered dogs were found to be 19 times (95% confidence interval: 2.1-172) more likely to require explant compared with intact dogs ( = 0.009). Every 0.25 mm increase in average pin size was found to make it 2.5 times (95% confidence interval: 1.3-4.9) more likely to require explant ( = 0.006).

Conclusion:  The findings suggest that use of the smallest appropriate pin should be considered for standard surgical repair of tibial tuberosity avulsion fractures to minimize the risk of requiring non-elective explant.