Equine Suspensory Ligament Disruption – NAVLE Study Guide

Overview and Clinical Importance

Suspensory ligament desmitis represents one of the most common causes of lameness in athletic horses across all disciplines. The suspensory ligament (also known as the interosseous muscle or musculus interosseus medius) is a critical component of the equine suspensory apparatus, serving to prevent hyperextension of the metacarpophalangeal (fetlock) joint during weight bearing. Understanding the anatomy, pathophysiology, diagnosis, and treatment of suspensory ligament injuries is essential for NAVLE success and clinical practice.

Injuries to this structure can affect any region of the ligament and occur in both forelimbs and hindlimbs. The clinical presentation, treatment approach, and prognosis differ significantly based on lesion location and severity, making accurate diagnosis critical for appropriate case management.

Functional Anatomy of the Suspensory Ligament

The suspensory ligament is an evolutionary derivative of the interosseous muscle found in other species. In horses, this structure has become predominantly tendinous (ligamentous), though it retains some muscle fibers, particularly in the proximal region. This mixed composition is clinically important and can complicate ultrasonographic interpretation.