COMPARISON OF RACING PERFORMANCE BEFORE AND AFTER TREATMENT OF INCOMPLETE, MIDSAGITTAL FRACTURES OF THE PROXIMAL PHALANX IN STANDARDBREDS -49 CASES (1986-1992)

Objective-To assess the effect of incomplete, midsagittal fractures of the proximal phalanx (P1) on racing performance in Standardbreds. Des ign-Retrospective cohort study. Animals-49 Standardbred horses admitte d to the George D. Widener Hospital for Large Animals between July 198 6 and December 1992 with a definitive radiographic diagnosis of an inc omplete, midsagittal fracture of P1 and a known method of treatment. P rocedure-Performance index and racing time were compared before and af ter diagnosis and treatment of fracture, using ANOVA that controlled f or the effects of horse, gender, age, track length, and track conditio n. Results-Expected racing time increased by 0.7 seconds and performan ce index decreased by 0.7 points, although controlling for factors kno wn to affect racing performance had a substantial impact on these resu lts. Clinical Implications-Standardbreds with incomplete, midsagittal fractures of P1 have a favorable prognosis for return to racing; recov ered horses will likely have slower racing times and decreased perform ance indices.