ABSTRACT
BACKGROUND: Repair of sagittal proximal phalanx (P1) and parasagittal metacarpal/metatarsal III (MC/MTIII) fractures has evolved over recent decades from a procedure carried out solely under general anaesthesia, to one commonly performed under standing sedation. To date, standing fracture repair has not been evaluated for large cohorts. OBJECTIVES: To determine short-term (survival to discharge) and long-term (return to racing) outcomes of horses undergoing standing repair of MC/MTIII and P1 fractures, and to compare pre-surgical and post-surgical racing performance. STUDY DESIGN: Single-centre retrospective cohort study. METHODS: Retrospective clinical record review of 245 cases undergoing standing repair of MC/MTIII or P1 fractures, 1 January 2007-30 June 2021. Data on signalment, fracture configuration and complications were collected and full race records were retrieved from the Racing Post Database (wwww.racingpost.com). Chi-squared and Mann-Whitney U tests were used to determine any difference in variables between horses that raced after surgery compared to those that did not. McNemar change and Wilcoxon signed-rank tests were used to compare pre- and post-surgical racing performance, p ≤ 0.05. RESULTS: Ninety-eight percent [95% confidence interval (CI): 96.2%-99.7%] of horses survived hospital discharge, and 75.1% (95% CI: 68.9%-81.4%) raced after surgery, a median of 241 days later. Horses that raced post-surgery were significantly less likely to have suffered from complications during hospitalisation than those that did not race again [17.3% (95% CI: 11%-24%) vs. 36.5% (95% CI: 23%-50%), p = 0.005]. Comparing pre- and post-operative racing performance, there was no significant difference in earnings per start [median £628.00, interquartile range (IQR) 115.90-1934.80 vs. £653.20, 51.00-1886.40, p = 0.7] or proportion of horses winning [51% (95% CI: 41%-61%) vs. 54% (95% CI: 44%-64%), p = 0.8] or being placed first-third [77% (95% CI: 68%-85%) vs. 71% (95% CI: 62%-80%, p = 0.5] in at least one race. MAIN LIMITATIONS: Retrospective nature of study with reliance on clinical records and public databases, limiting data available for analysis. CONCLUSIONS: Standing fracture repair is a viable treatment option for MC/MTIII or P1 fractures that returns horses to the racetrack within an acceptable time frame and is capable of restoring pre-surgical athletic ability.
ABSTRACT
Reasons for performing study: To investigate the racing performance of Thoroughbred horses with osseous cyst-like lesions (OCLLs) in the distal phalanx causing lameness and treated conservatively. Objectives: To assess horses' ability to race and perform after radiographic identification of OCLL in the distal phalanx of Thoroughbred horses with lameness at the time of detection and undergoing conservative treatment. Study Design: Retrospective case control study. Methods: The clinical database of one equine clinic was reviewed in a 10-year period for Thoroughbreds showing lameness localized to the foot and a radiographic diagnosis of OCLL in the distal phalanx. Sex, age at time of detection of the OCLL, degree of lameness, affected limb, and treatment were recorded. Successful performance of horses was assessed by racing at least once after detection of the OCLL and maximum racing performance rating (RPR). Radiographic features such as size, location, sclerotic rim of the OCLL and irregularity of the articular surface of the distal phalanx were compared to successful performance using univariable statistical analysis. Successful performance of horses with OCLL was compared to a control group of maternal siblings by parametric testing. Results: Twenty-two horses met the inclusion criteria. Thirteen horses raced after the detection of OCLLs. Eight did not race, one case had not yet reached racing age, resulting in 62% (13/21) of racing age racing at least once. The number of successfully performing horses with an OCCL was significantly lower compared to their maternal siblings [p = 0.03, Odds ratio (OR) = 0.30]. If horses with OCLL in the distal phalanx raced, their RPR was similar to their maternal siblings. No significant association was found between radiographic features of OCLLs and successful performance, but OCLLs in the left forelimb carried a more favorable outcome for racing (p = 0.02, OR = 2.33 95%CI 1.27, 4.27) compared to OCLLs in any other limb. Conclusions: Horses with lameness and an OCLL in the distal phalanx managed conservatively are less likely to race when compared to their maternal siblings. If horses with OCLLs in the distal phalanx are able to race, their performance, measured as RPR, was comparable to their maternal siblings. Due to the small numbers in this study the results should be interpreted carefully.
ABSTRACT
OBJECTIVE: To describe a lateral approach for screw fixation in lag fashion of simple spiral medial condylar fractures of the third metacarpus/metatarsus (MC3/MT3). STUDY DESIGN: Case series. ANIMALS: Thoroughbred racehorses (n=9). METHODS: Nondisplaced medial MC3/MT3 condylar fractures (3 thoracic, 6 pelvic limbs), with mean length 126 mm (range, 91-151 mm) were repaired by internal fixation, under general anesthesia, using multiple 4.5 mm cortical screws inserted in lag fashion from the lateral aspect of the limb, using radiographic or fluoroscopic guidance. Horses were recovered from anesthesia in half-limb casts; 7 unassisted and 2 using a rope-recovery system. Horses had 2 months box rest, 1 month in-hand walking, and follow-up radiographic examination at 3 months. RESULTS: Horses recovered uneventfully from anesthesia. Five horses raced; 1 returned to training, was persistently lame, and was retired to stud; 2 were retired directly to stud; and 1 horse was lost to follow-up. CONCLUSIONS: MC3/MT3 medial condylar fractures were successfully repaired by screws inserted n lag fashion form the lateral aspect. CLINICAL RELEVANCE: Use of a lateral approach to medial condylar MC3/MT3 fractures allows screw insertion perpendicular to the fracture plane without interference with palmar/plantar soft tissue structures or from the splint bones. Although repair was performed under general anesthesia, the technique should be adaptable to application in standing horses.
