The first step to treating a horse's wound is knowing what structures may be involved. | Photo: Anne M. Eberhardt/The Horse

Wounds are one of the more common injuries veterinarians assess in the field. And, when wounds occur near a joint or tendon sheath, there is always a risk the synovial structure is involved. If so, that becomes an even more serious problem.

Synovial structures include joints, tendon sheaths, and bursas (cushioning, fluid-filled sacs) contain synovial fluid that protects and lubricates the surrounding anatomy. When a wound involves a synovial structure, synovial fluid and, therefore, lubrication is lost, and infection can occur. Because wounds involving synovial structures are serious and can be life-threatening, veterinarians need to quickly assess whether a wound does, in fact, involve one of these structures.

The challenge becomes how best to do this in the field. The gold standards—synovial fluid cultures and cytology (examining cells under a microscope)—are either challenging on the farm, take days to get results, or are only helpful about 50% of the time, said Jacqueline Hill, DVM, Dipl. ACVS-LA, of Littleton Equine Medical Center, in Colorado. This leaves field veterinarians needing other tools with which to conduct an accurate assessment when treating a horse in the