Comparison of racing performance before and after treatment of incomplete, midsagittal fractures of the proximal phalanx in Standardbreds: 49 cases (1986-1992)

Abstract

Objective - To assess the effect of incomplete, midsagittal fractures of the proximal phalanx (P1) on racing performance in Standardbreds. Design - Retrospective cohort study. Animals - 49 Standardbred horses admitted to the George D. Widener Hospital for Large Animals between July 1986 and December 1992 with a definitive radiographic diagnosis of an incomplete, midsagittal fracture of P1 and a known method of treatment. Procedure - Performance index and racing time were compared before and after diagnosis and treatment of fracture, using ANOVA that controlled for the effects of horse, gender, age, track length, and track condition. Results - Expected racing time increased by 0.7 seconds and performance index decreased by 0.7 points, although controlling for factors known to affect racing performance had a substantial impact on these results. Clinical Implications - Standardbreds with incomplete, midsagittal fractures of P1 have a favorable prognosis for return to racing; recovered horses will likely have slower racing times and decreased performance indices.