Equine Nonseptic Synovitis and Bursitis Study Guide

Overview and Clinical Importance

Nonseptic synovitis and bursitis represent common causes of joint effusion and lameness in equine practice. These conditions involve inflammation of synovial structures without bacterial infection, distinguishing them from the more serious septic counterparts. Understanding the pathophysiology, clinical presentation, and management of these conditions is essential for the NAVLE examination and clinical practice.

Synovial structures in horses include joints, tendon sheaths, and bursae. When inflammation occurs without infection, it is termed nonseptic or aseptic synovitis or bursitis. These conditions can range from mild, cosmetic concerns to performance-limiting lameness, depending on the underlying cause and severity.

Anatomy of Equine Synovial Structures

Synovial structures are lined by a synovial membrane composed of specialized synoviocytes that produce synovial fluid. This fluid contains hyaluronic acid and lubricin, which provide joint lubrication and nutrition to avascular articular cartilage. The synovial membrane is highly vascularized and innervated, making it responsive to injury and inflammation.