title: Racing performance of Swedish Standardbred trotting horses with proximal palmar/plantar first phalangeal (Birkeland) fragments compared to fragment free controls.
abstract: The aim of this study was to determine whether horses with a proximal palmar/plantar first phalangeal osteochondral fragment (POF) had comparable racing careers (prior to and following surgery) to horses without this fracture. A retrospective cohort study included 174 Swedish Standardbred trotters with osteochondral fragmentation in the palmar/plantar fetlock joint and 613 radiographically negative control horses presented for prepurchase examinations. Medical records and radiographs were examined for each horse. Racing data were retrieved from online Swedish Standardbred harness racing records. The effect of having a POF on race speed compared to radiographically negative control horses was examined using generalised estimating equations. Multivariable regression was used to examine differences in money earned and career longevity. The horses raced a total of 16,448 races. Horses gained speed as a function of race number. There was no difference in racing speed between horses with POF fractures that raced before surgery and control horses. Horses did not slow before, nor speed up after, surgery. There was no difference in the number of days between the last race prior to, or the first race after, the hospital visit between POF and control horses. Career earnings and lifetime starts were not significantly different between groups. The results of this study suggest the need to reevaluate the previously reported benefits of surgical intervention for POF.
authors.affiliation: Hallands Djursjukhus, Björkgatan 19, 31168 Slöinge, Sweden; Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada. Electronic address: james.carmalt@usask.ca.
authors.forename: James L
authors.initials: JL
authors.lastname: Carmalt
authors.affiliation: Hallands Djursjukhus, Björkgatan 19, 31168 Slöinge, Sweden.
authors.forename: Hanna
authors.initials: H
authors.lastname: Borg
authors.affiliation: Hallands Djursjukhus, Björkgatan 19, 31168 Slöinge, Sweden.
authors.forename: Hans
authors.initials: H
authors.lastname: Näslund
authors.affiliation: Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada.
authors.forename: Cheryl
authors.initials: C
authors.lastname: Waldner
mesh_terms: D000818:Animals; D015331:Cohort Studies; D005260:Female; D005552:Forelimb / Q000473:pathology; D050723:Fractures, Bone / Q000662:veterinary*; D006614:Hindlimb / Q000473:pathology; D006734:Horse Diseases / Q000175:diagnosis* / Q000473:pathology; D006736:Horses / Q000293:injuries*; D008297:Male; D012189:Retrospective Studies; D013177:Sports; D013548:Sweden
keywords: Birkeland; Equine; First phalanx; Fractures; Racing; Surgery