Septic Arthritis and Tenosynovitis: Diagnosis and Treatment

Bacterial infection of synovial structures, most commonly septic arthritis and septic tenosynovitis, represent potentially devastating musculoskeletal conditions for horses of any type. Bacterial infection of joints and sheathes results in profound inflammation of the synovial membrane and surrounding tissues and may result in rapid, permanent damage to tissues within the joint or sheath.

The cause of infection is most commonly perforating injury, intra-articular injection, or post-operative infection of the joint or surrounding tissues that ultimately accesses the joint. Idiopathic infections occur but are rare. Elucidating the cause of infection is often of use; enteric bacteria are frequently implicated in traumatic injuries, while Staphyloccocus aureus is the predominant isolate from iatrogenic lesions.

Table 1. Comparison of local antimicrobial delivery methods

Clinical Findings and Diagnosis

As is the case in man, septic arthritis/tenosynovitis constitutes a medical emergency. Clinical experience and most reports indicate that delays in therapy are often associated with progressive tissue destruction and morbidity and a decidedly less favorable prognosis.

Although uncertain, the diagnosis of septic arthritis can often be made on clinical grounds, once fractures or soft tissue infection (subsolar abscess) is eliminated. Indeed, there are few other reasons for profound lameness and effusion in a joint in an adult horse. In addition to pronounced lameness, there is typically demonstrable heat, swelling (both ...