Impairment of osteophyte formation in hyperglycemic patients with type II diabetes mellitus and knee osteoarthritis

Objective. Since insulin is a potent growth factor for connective tissue, the present study was designed to investigate whether radiographic features of knee osteoarthritis (OA) in patients with poorly controlled, insulin‐resistant type II diabetes mellitus differ from those in nondiabetic controls with knee OA. Methods. Radiographs from 25 female patients with diabetes and knee OA were compared with those from 48 female controls who were similar with respect to age, weight, and duration of OA symptoms. Results. Although the 2 groups were similar with respect to the frequency and severity of joint space narrowing, subchondral sclerosis, and geodes, osteophytes were less common in the patients with diabetes (P = 0.044), and spurring, when present, tended to be ‘marked’ less often in the diabetic patients than in the controls. Conclusion. The data suggest that diminished availability of insulin at the cellular level or diabetic microvascular disease attenuates the chondro‐ and osteogenesis required for osteophyte formation in the joints of patients with OA.