Often experience tells us that we can’t go wrong with pasture rest, when it comes to healing our horses. But could pasture rest alone be the ideal treatment for stress remodeling in horses’ cannon bones? According to the results of a recent study by a team from Rood & Riddle Equine Hospital, in Lexington, Ky., turning a horse diagnosed with stress remodeling–a relatively common cause of lameness–out to pasture could allow him the best chance to return to his previous level of work.

Described by lead researcher Travis M. Tull, DVM, Dipl. ACVS, a "cumulative stress-induced bone injury" throughout the study, stress remodeling is a process in which a bone tries to adapt its structure when exercise demands exceed what it can handle. Such remodeling likely predisposes the horse to injury: "If the bone cannot adapt fast enough to the stress of training and racing, horses can develop microstructural or microscopic pathology, leading to lameness, condylar fracture, and fetlock arthritis," Tull explained.

Stress remodeling is often to blame for lameness and poor performance in Thoroughbred and Standardbred racehorses. Stress remodeling can affect other types of performance horses, however Tull noted that cannon bone involvement is not as common in disciplines besides racing.

Previous studies indicated that stress remodeling in the lower cannon bones yielded a poor prognosis, and only 40%-54% of case horses were able to return to their previous levels of work. These horses were treated with stall rest, and intra-articular (within the joint) and systemic medications (including hyaluronic acid and polysulfated glycosaminoglycan injections)