LAG SCREW FIXATION OF NONCOMMINUTED SAGITTAL FRACTURES OF THE PROXIMAL PHALANX IN RACEHORSES - 59 CASES (1973-1991)

Medical records of 59 racehorses with noncomminuted midsagittal proxim al phalanx fractures repaired by means of lag screw fixation between 1 973 and 1991 were reviewed. Fractures were classified as short incompl ete fractures (7), long incomplete fractures (32), complete fractures extending into the proximal interphalangeal joint (13), and complete f ractures extending through the lateral cortex of the proximal phalanx (7). Time from fracture repair to first race following fracture repair , number of racing starts, and fastest race times before and after sur gery were obtained from race records and compared among houses grouped by fracture type and between horses that returned to racing and those that did not race. Five horses with shore incomplete fractures, 21 ho rses with long incomplete fractures, 6 horses with complete fractures extending into the proximal interphalangeal joint, and 5 horses with c omplete fractures extending fo the lateral cortex returned to racing. A significantly lower percentage qi horses returned to racing followin g repair of complete fractures extending into the proximal interphalan geal joint (46%), than following repair of short incomplete fractures (71%), long incomplete fractures (66%), ou complete fractures extendin g to the lateral cortex (71%). Time from fracture to repair for houses that returned to racing (mean, 14.7 days; range, 1 to 60 days) was no t significantly different from that for horses thai did not race (mean , 5.8 days; range, 1 to 21 days). For all fracture groups, median numb er of races before injury was not significantly different from median number of races after repair, and median fastest race time before frac ture was not significantly different from median fastest race time aft er fracture repair.