Tibial plateau levelling osteotomy implant removal: A retrospective analysis of 129 cases.

Objective: To evaluate a cohort of dogs undergoing tibial plateau levelling osteotomy (TPLO) implant removal to determine key clinical features, prevalence, and indications for implant removal. Methods: Medical records of dogs undergoing TPLO implant removal at a private referral practice (Dallas Veterinary Surgical Center) between 2004-2008 were reviewed. Patient signalment, implant type, presence of concurrent medical disease, surgeon, antibiotic use, aerobic bacterial culture result, and operative findings were recorded. Data were analyzed using paired t-test, Fisher's exact test, and Wilcoxon-rank sum test. Statistical significance was set at p <0.05. Results: The TPLO implants were removed from 126 dogs (n = 129, 4.8% of TPLO procedures) during the study period. Average time interval from TPLO to implant removal was 16.0 ± 17.8 months. The most common clinical signs were the presence of an open wound (n = 80), draining tract (n = 64), and lameness (n = 59). Culture of tissue or fluid from the implant bed or implants was positive for bacterial growth in 95/115 cases. A significantly greater proportion of the implants removed were Slocum TPLO plates (n = 109; 6.1%) when compared to other TPLO plate types (n = 20; 2.3%) (p <0.0001). No association was identified between a positive bacterial culture and measured variables. Clinical significance: Local bacterial infection and clinical signs of inflammation were the most common reasons for TPLO implant removal. There may be an increased implant-associated complication rate for Slocum TPLO plates in the study population.