The Canine Elbow Anatomy

By Anna Lloyd and Kirsten Straszacker

Anatomy forms the very foundation of everything we do as Vetrehabbers, and (un)fortunately, it’s an area we should be constantly reviewing and studying!

This month, we dive into the canine elbow. We’ll discuss it’s classification, stabilisation, mobility and, of course, the anatomical structures that allow each component of movement.

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Joint classification

The elbow is a composite joint that includes the humerus, radius and ulna. The humeroulnar and humeroradial joints are both hinge joints, while the proximal radioulnar joint is a pivot joint and the mid-radioulnar joint is a syndesmosis joint.

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Physiological movement available

Within the humeroradioulnar joints, flexion and extension occur in the sagittal plane through the transverse axis of movement. This flexion and extension is an essential component of the functional movement of the dog, allowing the forelimb to protract and retract during a normal gait cycle. Flexion of the elbow is essential during functional movements such as jumping, climbing stairs, and lying down.

Within the radioulnar joint, pronation and supination occur in the transverse plane through the ventrodorsal axis of movement. Pronation and supination allow the dog to turn and pivot, and to adjust to changes in the surface of the terrain. It is also essential during self-grooming activities.

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Stabilisation of the elbow

The elbow joint is stabilised by a series of structures. The shape of the humeroulnar portion provides stability to the joint and restricts movement to the sagittal plane. Lateral movement of the joint is restricted by the medial and lateral collateral ligaments, as well as the anconeal process that extends into the olecranon fossa of the humerus.

The annular ligament runs transversely around the radius from the lateral to the medial coronoid processes of the ulna. Other ligaments of the elbow include the olecranon ligament and the oblique ligament.

The joint capsule surrounds the entire humeroradioulnar joint, and communicates with the proximal radioulnar joint.?

The radius and ulna are primarily united by the strong interosseus ligament (Hermanson et al., 2020).

Read the full article with anatomical illustrations, here