New research shows that spraining the ankle can boost the risk of developing osteoarthritis (OA) in that joint. The finding indicates that intensive rehabilitation after such injury is needed to help ward off OA. Experts have known for years that OA in the ankle often occurs after a fracture, but it has long been debated whether recurrent sprains or instability alone without fracture can also lead to OA. The new research supports this idea. The findings were presented at the American Orthopaedic Foot and Ankle Society annual winter meeting in Washington, DC.
Swiss researchers evaluated 268 patients with OA of the ankle. Of these patients, 221 had had a fracture, and 47 experienced chronic ankle instability with recurrent sprains but no fractures. It took about 22.5 years for OA to develop in the sprain group, compared with 21 years for the fracture group. Researchers said that OA could develop after an ankle sprain, due to lingering instability and increased forces at the surface of the joint. Up to 40% of patients with ankle injuries experience chronic instability in the joint, the researchers noted, and up to 80% of these people develop OA in the ankle.