Retrospective analysis of lameness localisation in Western Performance Horses: A ten-year review.

BACKGROUND: Similar to other high-level athletic disciplines, the western performance horse experiences a variety of orthopaedic conditions as a result of rigorous sport-specific physical demands. While musculoskeletal injury rates have been quantified in other equine disciplines, these data are lacking for the western performance athlete. OBJECTIVES: To identify the most common anatomical regions of lameness in western performance horses being evaluated at the nation's largest sanctioned shows over a 10-year study period. STUDY DESIGN: Retrospective review of clinical records. METHODS: Records of diagnostic analgesia of western performance horses competing at nationally sanctioned shows were retrospectively reviewed over a 10-year period to identify affected limb(s) and lameness localisation patterns. RESULTS: A total of 2267 lameness examinations on 2512 horses were included. The average lameness grade was 2.21/5 with 1504/2267 (56%) cases being primarily forelimb in origin while 1173/2267 (44%) were hindlimb related. Forelimb lameness localised to the distal limb in 40% of cases. The proximal metatarsus/distal tarsus was an identified source of lameness in 16% of cases, followed by the stifle in 9% of cases. All-around western performance horses most commonly presented with a single hindlimb lameness (315/1188, 26.5%) in contrast to reining horses that presented with a single forelimb lameness (135/616, 22%). DISCUSSION: Determining the source of lameness through diagnostic analgesia remains challenging, but the continued assessment of response to diagnostic analgesia may help characterise discipline-specific injuries in western performance horses. MAIN LIMITATIONS: Retrospective review of subjective responses to diagnostic analgesia. CONCLUSIONS: The distal forelimb and distal tarsus/proximal metatarsus were the two most common anatomical regions of lameness based on response to diagnostic analgesia.

Prospective randomized comparison of platelet rich plasma to extracorporeal shockwave therapy for treatment of proximal suspensory pain in western performance horses.

Proximal suspensory desmitis (PSD) is a frequent cause of lameness in the performance horse. Extracorporeal shockwave therapy (EST) and platelet rich plasma (PRP) have become common treatments for PSD yet clinical data on efficacy is limited. The main objective of this randomized, prospective clinical study was to compare long-term effectiveness of EST and PRP in Western performance horses. One hundred horses with lameness localized to the proximal suspensory ligament received treatment with either PRP or EST following baseline ultrasonographic evaluation. A veterinarian and agent evaluated the horses for lameness independently four days following the first treatment and long-term follow up was obtained from the agent at six and twelve months. Four days post treatment, horses treated with EST had significantly greater lameness improvement compared to PRP. At one-year horses with less severe baseline ultrasound changes (grades 0-1) appeared to respond better (degree of lameness) with EST treatment whereas horses with more severe ultrasound changes (grade 2) responded better to PRP. Horses with baseline lameness graded 1 or 2 were 5.1 times more likely to be back in work at 1 year compared to those presenting with grade 3 or 4. EST treatment was associated with going back to work 3.8 times more at one year compared to PRP independent of baseline ultrasound score. Both PRP and EST can be expected to yield favorable therapeutic responses in Western performance horses with lameness localized to the proximal suspensory region. Baseline ultrasound may guide treatment selection.