Tendon Volume Determination on Magnetic Resonance Imaging of Supraspinatus Tendinopathy

Abstract

Objective: To determine the supraspinatus tendon volume using magnetic resonance imaging (MRI) in dogs with non-calcified supraspinatus tendinopathy (NCST), in dogs with orthopedic disease other than NCST, and in healthy dogs. Study Design: Case series. Animals: Twenty-two dogs (18 client-owned dogs; 4 purpose-bred dogs). Methods: Dogs undergoing shoulder MRI were categorized as NCST if they were diagnosed with NCST only, had histologic confirmed diagnosis, underwent surgical treatment, and were available for follow-up longer than 4 months. Dogs with MRI performed for a forelimb lameness because of a diagnosis other than NCST were categorized as orthopedic control (OC). Healthy dogs from an unrelated study were categorized as healthy controls (HC). Tendon volume was determined from MRI using public domain software and compared across categories. Results: The study included 9 NCST dogs, 9 OC dogs, and 4 HC dogs. The median tendon volume for NCST was 1,323mm3, OC was 630mm3, and HC was 512mm3. The volume was significantly higher in the NCST than OC (P=.0012) and HC (P=.003). There was no difference between OC and HC (P=.76). Conclusion: Dogs diagnosed with NCST had higher supraspinatus tendon volumes compared to dogs with other orthopedic disorders and healthy dogs.