Kinematics of the cervical spine of the adult horse.

This research study investigates the movement patterns of each intervertebral joint in the neck of adult horses. It uncovers that at least three types of movement — dorsoventral flexion and extension, axial rotation and lateral bending — occur at each joint. Specific patterns, variations, and limitations in these movements are thoroughly analysed and presented.

Objectives of the Study

• The main objective of this study was to examine the movement patterns of the cervical spine (neck) of a horse. This was conducted through the exploration of dorsoventral flexion and extension, axial rotation, and lateral bending at each of the intervertebral joints.

Key Findings

• At the joint between the first two cervical vertebrae, the mean axial rotation was identified as 107.5 degrees. This accounts for 73% of the total axial rotation in the cervical spine.
• The atlantooccipital joint (between the skull and the first vertebra) has a mean rotation of 27 degrees, while the other cervical joints demonstrated less than 3 degrees of rotatory movement.
• Most dorsoventral flexion (forward and backward bending) and extension are located at the atlantooccipital joint, with an amplitude of 86.4 degrees, representing 32% of the total dorsoventral movement of the cervical spine.
• Lateral bending (side-to-side movement) is more uniform along the neck, with mean values ranging between 25 to 45 degrees at each joint, except the first two cervical vertebrae, which had a mean of only 3.9 degrees of lateral bending.

Significance of the Research

• This profound examination of the kinematics of the equine cervical spine provides a structured understanding of the physiological limits and variances in movement. This can contribute to the better management of horse health, particularly in terms of preventing or mitigating spinal injuries.
• The findings could also pave the way for further research on related matters. For example, detailing how these movement patterns differ across various equine breeds, ages, or activity levels.