Traumatic elbow luxation in cats: A cadaveric study on the role of collateral and olecranon ligaments in joint stability.

Objective: To determine the role of each part of the collateral ligaments and the olecranon ligament in traumatic elbow luxation pathophysiology in cats.

Study design: Feline cadaveric study.

Sample population: A total of 15 cats and 30 thoracic limbs tested.

Methods: Attempts were made to manually luxate (laterally, medially, and caudally) each elbow after sequential section of each part of the medial collateral ligament, the lateral collateral ligament, and the olecranon ligament by direct and indirect forces applied to the antebrachium.

Results: No elbow luxation occurred with indirectly applied rotational forces. Luxation was only possible with direct forces applied to the antebrachium (axial compression and varus/valgus/caudal forces). Lateral elbow luxation was possible after transection of medial and lateral collateral ligaments or after transection of olecranon and medial collateral ligaments. Medial luxation was possible after transection of olecranon and lateral collateral ligaments. Caudal luxation was possible with transection of olecranon and lateral collateral ligaments.

Conclusion: Various combinations of ruptured ligaments can account for lateral, medial, and caudal luxations of the elbow. The olecranon ligament plays a major role in elbow stability.

Clinical significance: Traumatic elbow luxation in cats can happen with only one collateral ligament rupture, if the olecranon is concurrently severed. The integrity of each ligament should be assessed before any repair.