Longitudinal Study of Cartilage Degeneration Patterns in Canine Elbow Dysplasia Using Advanced Imaging and Synovial Biomarker Analysis in South West Nigeria

Elbow dysplasia represents the most common cause of forelimb lameness and early osteoarthritis in large breed dogs, yet the longitudinal progression of cartilage degeneration and its correlation with synovial biomarker dynamics has not been characterized in a Nigerian population. This doctoral study undertakes a two-year prospective longitudinal investigation of cartilage degeneration patterns in dogs with confirmed elbow dysplasia using high-field MRI, computed tomography, and biochemical synovial fluid biomarker analysis at a veterinary referral center in Lagos, South West Nigeria, between 2022 and 2024. Forty-two large breed dogs with arthroscopically confirmed elbow dysplasia were enrolled and followed at six-monthly intervals. Cartilage T2 mapping MRI sequences were used to assess compositional cartilage changes. Synovial fluid was collected at each assessment for analysis of cartilage oligomeric matrix protein, collagen type II degradation biomarkers, and matrix metalloproteinase activity. MRI cartilage T2 values demonstrated progressive deterioration in all enrolled dogs over 24 months, with the medial coronoid process articular cartilage showing the earliest and most severe degeneration. Synovial cartilage oligomeric matrix protein concentrations correlated significantly with MRI cartilage T2 change at 12 and 24 months. Dogs with bilateral disease progressed faster than unilateral cases. Arthroscopic intervention within six months of diagnosis significantly attenuated biomarker progression trajectories. This longitudinal dataset provides original mechanistic insights into canine elbow dysplasia progression in a tropical African population and identifies biomarker-imaging correlates useful for monitoring disease-modifying treatment efficacy. Keywords: elbow dysplasia, cartilage degeneration, MRI biomarker, longitudinal study, canine orthopedics.