Destabilization of the medial meniscus in geriatric mice captures functional decline in age-associated osteoarthritis

Abstract

Osteoarthritis (OA) disproportionately affects older adults, yet most preclinical models rely on young animals and fail to incorporate biological aging. Here, we establish a geriatric murine model of OA using destabilization of the medial meniscus (DMM) in 18–19-month-old C57BL/6J mice. Surgical induction produced joint pathology consistent with OA, including loss of cartilage integrity and osteophytic remodeling. Functionally, OA mice exhibited increased composite ethogram scores and reduced rearing behavior, indicating impaired mobility and weight-bearing capacity. These findings demonstrate that DMM surgery in aged mice induces both structural and functional features of OA. This model provides a practical and physiologically relevant platform for studying age-associated joint degeneration and evaluating therapeutics in an aging context.

Keywords: Osteoarthritis, aging, destabilization of the medial meniscus, C57BL/6J mouse model, knee joint degeneration, functional impairment