ABSTRACT
REASONS FOR PERFORMING STUDY: Intra-articular (IA) injection of corticosteroids with or without hyaluronate (HA) has been used for decades in equine practice for treatment of noninfectious synovitis and osteoarthritis. However, to date, no large-scale randomised equine field trials have been reported that address the supposed superior clinical efficacy of the combination of corticosteroid + HA compared with IA injection of corticosteroid alone. OBJECTIVES: To compare the clinical efficacy of IA triamcinolone acetonide (TA, 12 mg) compared with IA TA (12 mg) + high molecular weight HA (20 mg) in horses with clinical joint disease. STUDY DESIGN: Prospective, randomised, parallel, open label, multicentre clinical trial. METHODS: Eighty client-owned horses from 13 clinics were included. Lameness and effusion scores were assessed at baseline and 3 weeks after IA treatment. A standardised telephone questionnaire was completed between the owner and consulting veterinarian at 3 months. The primary outcome parameter was clinical success rate, defined as ≥2 grades lameness reduction (on a 0-5 scale) at 3 weeks. Chi-square statistics and binary logistic regression were used to analyse data on an intention-to-treat basis for the 3 week outcome. RESULTS: The success rate of IA TA 3 weeks after treatment was 87.8%, while that of TA+HA was 64.1% (P = 0.01). Age >13 years was associated with a reduced success rate for the combination treatment (P = 0.004) at 3 weeks. At 3 months, half the horses in each group had returned to their previous level of performance. CONCLUSIONS: The combination of TA with HA was associated with a lower short-term clinical success rate and a similar medium-term outcome compared with IA TA, with only half of the horses performing at their previous level of exercise after 3 months regardless of treatment group allocation.
