Distribution of Pelvic Fractures in Racing and Non-racing Sport Horses: A Retrospective Study of 86 Cases Examined in a Referral Centre.

Abstract

The aim of this study was to analyse the pelvic fracture distribution and location in a referral centre caseload. Medical records of 6,717 horses examined in a referral centre over a 7-year period were reviewed to identify all horses diagnosed with a pelvic fracture. Eighty-six horses were identified and divided into three disciplines, namely Thoroughbred racehorses (TBR), Standardbred trotter racehorses (STR) and non-racing sport horses (NRSH). A pelvic fracture was diagnosed in 1.3% of the cases examined during the study period. Prevalence was significantly higher in TBR (4.2%) and, regardless of the discipline, in horses under the age of 6 years (2.2%) (p < 0.01). STR were significantly younger than TBR and NRSH at the time of fracture (median ages = 1, 3 and 4 years old, respectively; p < 0.01). The fractures occurred most frequently in the ilium (44/86). No ilial wing fractures were diagnosed in STR and isolated acetabular fractures were only diagnosed in foals and yearlings. Fatigue fractures were diagnosed in TBR alone, affecting 9/22 TBR (foals and yearlings excluded) and most often located in the ilial wing (7 fatigue fractures out of the 12 ilial wing fractures) (p < 0.01). The median age of horses suffering from a pelvic fatigue fracture was 4 years. This study confirms that young horses (under the age of 6 years) as well as TBR are likely to be at higher risk of a pelvic fracture. Fatigue fractures of the ilial wing seem to be a rare condition in STR while they are more frequent in young TBR in training.