Racing performance after surgical repair of medial condylar fracture of the third metacarpal/metatarsal bone in thoroughbred racehorses.

OBJECTIVE: To report the performance of thoroughbred racehorses after surgical repair of a medial condylar fracture of the third metacarpal/metatarsal bone. STUDY DESIGN: Retrospective cohort study. SAMPLE POPULATION: Forty-three horses surgically treated for medial condylar fractures, 30 with previous racing experience, 13 without previous racing experience (nonexperienced). METHODS: Medical records (2009-2017) were reviewed for signalment, radiographic fracture characteristics, repair technique, and postoperative morbidity and mortality. Each experienced horse was matched with two horses randomly selected from its most recent race to serve as healthy controls. Racing performance parameters (race rating, competitive level, speed rating, performance index) and career racing statistics were compared with multiple regression models between injured experienced horses and controls. The career racing statistics for nonexperienced horses were evaluated. Reasons for nonreturn to racing were obtained. RESULTS: The median duration of follow-up was 6 years (minimum 2, maximum 10). Twenty-one of 43 (49%) horses raced again as well as 18 of 30 (60%) experienced horses and three of 13 (23%) nonexperienced horses. Experienced horses were five times more likely than nonexperienced horses to return to racing (95% confidence interval = 0.07-0.58, P = .003). Higher preoperative racing performance parameters were associated with return to racing. Racing performance parameters were lower after the date of fracture in injured horses compared with controls. CONCLUSION: Experienced horses were more likely to return to racing after medial condylar fracture repair, although their performance was generally lower than that of comparably uninjured horses. CLINICAL SIGNIFICANCE: Owners should be aware that horses with medial condylar fractures likely will race at a lower level than their uninjured peers.

Surgical repair of mid-body proximal sesamoid bone fractures in 25 horses.

OBJECTIVE: To describe the characteristics of unilateral mid-body proximal sesamoid bone (PSB) fractures, to determine factors associated with the outcome of horses after surgical repair, and to describe a technique for arthroscopically assisted screw fixation in lag fashion. STUDY DESIGN: Retrospective case series. ANIMALS: Horses (n=25) with unilateral mid-body PSB fracture. METHODS: Medical records (1996-2006), radiographs, and arthroscopic videos of horses with surgically repaired unilateral mid-body PSB fractures were reviewed. Retrieved data included signalment, affected limb and PSB, fracture characteristics, and surgical technique. Outcome was established by radiographic assessment of healing and race records; categorical data were analyzed using Fisher's Exact test. RESULTS: Medial forelimb PSBs were most commonly affected (80%). Surgical technique and degree of reduction were significantly associated with outcome; 44% of horses with screw repair and none of the horses with wire fixation raced (P=.047). Factors that may have influenced this outcome were differences in fracture reduction (improved reduction in 22% wire repairs and 88% screw repairs, P=.002) and use of external coaptation (22% wire repair and 88% lag screw repair, P=.002). None of the horses with unimproved reduction raced after surgery. CONCLUSIONS: Only 28% of horses with mid-body PSB fractures raced after surgery. Compared with wire fixation, screw fixation in lag fashion resulted in good reduction and is seemingly a superior repair technique. CLINICAL RELEVANCE: For mid-body PSB fractures, arthroscopically assisted screw fixation in lag fashion and external coaptation for anesthesia recovery and initial support provides the best likelihood of return to athletic use.