Investigation of the Role of Matrix Metalloproteinases in Degenerative Joint Disease Progression in Nigerian Canine Patients: Implications for Surgical Timing

Degenerative joint disease in dogs is a progressive condition driven by complex enzymatic cascades including matrix metalloproteinase-mediated cartilage degradation, and understanding these mechanisms in the Nigerian canine population has direct implications for optimizing surgical intervention timing. This doctoral study investigates the role of matrix metalloproteinases, specifically MMP-1, MMP-3, and MMP-13, in the progression of degenerative joint disease in canine patients presenting with primary joint pathologies at teaching hospitals in Lagos, Ibadan, and Enugu States between 2022 and 2024. Synovial fluid and serum samples from 96 dogs were analyzed at enrollment and at six-monthly intervals for two years using enzyme-linked immunosorbent assay for matrix metalloproteinase quantification. Radiographic joint scoring and force plate gait analysis were performed concurrently. Synovial MMP-3 and MMP-13 concentrations were significantly elevated in dogs with moderate to severe radiographic osteoarthritis compared to mild disease and healthy controls. Longitudinal analysis demonstrated that MMP-13 surge preceded radiographic deterioration by a mean of four months, identifying a potential biochemical window for pre-radiographic surgical intervention. Dogs undergoing joint-stabilizing surgery at this biochemical window stage demonstrated significantly slower MMP-13 progression trajectories at 12-month follow-up compared to dogs operated at later radiographic stages. These mechanistic findings provide the first longitudinal matrix metalloproteinase characterization of canine degenerative joint disease progression in Nigeria, offering a biochemical rationale for earlier surgical timing criteria that may substantially delay disease progression and improve long-term functional outcomes. Keywords: matrix metalloproteinases, degenerative joint disease, canine, cartilage degradation, surgical timing.