Racing performance after arthroscopic removal of apical sesamoid fracture fragments in Thoroughbred horses age ≥ 2 years: 84 cases (1989-2002)

Abstract

Summary Reasons for performing study: Studies have shown that surgical removal of apical fracture fragments in Standardbred racehorses carries the best prognosis for return to racing performance, but there are no reports involving mature Thoroughbred (TB) racehorses. Objectives: To describe the incidence of apical proximal sesamoid fractures in TB racehorses and determine probability and quality of racing performance after arthroscopic removal of such fractures in TB racehorses age ≥2 years. Methods: Medical records and pre‐ and post operative race records of TB racehorses age ≥2 years that underwent arthroscopic surgery for removal of apical proximal sesamoid fracture fragments were reviewed. Results: Sixty‐four percent of fractures occurred in the hindlimbs and 36% in the forelimbs. Horses with forelimb fractures had a reduced probability of return to racing (67%) compared to those with hindlimb fractures (83%), but the majority (77%) of treated horses recovered to return to race post operatively. Horses with medial forelimb fractures raced at only a 47% rate; those with suspensory desmitis at 63%. Unlike Standardbreds, there was no difference in probability of racing post operatively between horses that had, and had not, raced preoperatively. Conclusions: Data show that arthroscopic removal of apical proximal sesamoid fracture fragments is successful at restoring ability to race in skeletally mature TB horses without evidence of severe suspensory ligament damage. Prognosis for return to racing is excellent (83%) in horses with hindlimb fractures and good (67%) in those with forelimb fractures. Medial fractures of the forelimb have the worst prognosis. Potential relevance: The determination of prognosis for differing sites in TB racehorses should increase knowledge of apical proximal sesamoid bone fractures and improve communication from veterinarian to owner, and trainer, on the potential for arthroscopic restoration of the ability to race.

Relationship between Brazilian Thoroughbred race horses performance and lay-up period after osseous thoracic limb diseases

“…Such evidence contrasts with the results of GOMES & ALVARENGA (1998) who showed that even with a mean of 161 lay-up days (considered extensive in the present study), later athletic performance of the evaluated horses was inferior to previous performance. Similar results were reported by SCHINABEL et al (2006) who found that even with a mean of 368 rehabilitation days, the majority of the evaluated animals did not show improvement in their later performances. One important reason for the discrepancy in the results could have been that the above cited authors evaluated the recovery from arthroscopic removal of fracture fragments whose challenge was perhaps greater than that faced by the animals of the present study.…”

“…On the other hand, GOMES & ALVARENGA (1998) and SCHINABEL et al (2006) assessed rehabilitation time following arthroscopic surgery using the number of days until the fi rst race without a temporal scale of categories. Regarding performance evaluation, GOMES & ALVARENGA (1998) determined only the percentage of classifi cations and total number of previous and later races, and did not make clear the categorization of the type of race on which the evaluation was based.…”

Diagnostic and Surgical Arthroscopy of the Metacarpophalangeal and Metatarsophalangeal Joints

“…Subsequently, Schnabel et al (2006Schnabel et al ( & 2007 reported the results of arthroscopic removal of apical sesamoid fracture fragments in Thoroughbred racehorses. Of Thoroughbreds 31 out of 38 (82%) ran at the same or at an improved level (Schnabel et al, 2006).…”

“…Of Thoroughbreds 31 out of 38 (82%) ran at the same or at an improved level (Schnabel et al, 2006). Horses with medial proximal sesamoid bone fractures were less likely (26 out of 40; 65%) to race postoperatively than those with lateral fractures (35 out of 39; 90%).…”

“…The presence of suspensory desmitis in the affected limb also has a negative association with postoperative performance; 63% of horses with identified suspensory desmitis raced postsurgery compared with 77% without. In a second paper (Schnabel et al, 2007) these authors assessed the racing performance of 151 Thoroughbreds that had apical sesamoid fragments removed arthroscopically when younger than 2 years of age. Among these horses, 123 out of 147 (84%) raced postoperatively and there was no difference between their performance and maternal siblings.…”