Movements of the Horses Back

The back is anatomically described as the thoracolumbar spine, the part of the spine between the highest point of withers (T3 / T4) and the beginning of the quarters. The head, neck and tail are not a part of the thoracolumbar spine and it does not include the scapulas or the pelvis, which support the back at either end.

The horses back is designed for support, stability and protection rather than for movement. The range of movement betweens the horse’s thoracic vertebrae is strictly limited due to the dense fibrous intervertebral discs. Designed for strength, shock absorption and minor movement.

The horses back is only capable of very minor movement in both dorsal-and-ventral and side-to-side directions, sometimes as a result of forces transmitted from the pelvic limbs. Three areas of the horses spine should be highlighted that are capable of a reasonable range of movement:

_ The junction between the last cervical vertebrae C7 and the first thoracic vertebrae T1 _ At the lumbar sacral junction L6 S1. This joint allows for local flexion as the pelvic limb moves into protraction under the body, followed by extension as the pelvic limb thrusts the body mass forward. _ The junction between the last thoracic vertebrae T18 and the first lumber vertebrae L1, allowing for a limited range of flexion and extension.

In some instances movements in one part of the spine are related to movements in another region i.e. when the head and neck are lowered the back appears rounded (moves dorsally) and when the head and neck are raised the back appears hollowed (moves ventrally). The thoracolumbar spine remains stable during any activity with the musculature being designed for support.