Musculus scalenus ventralis
The ventral scalene is the ventral component of the scalene muscles. It originates from the transverse processes of the lower cervical vertebrae and inserts on the ventral surface of the first rib. Its actions are to elevate the first rib, assist inspiration, and produce lateral flexion of the neck. It is innervated by ventral branches of lower cervical spinal nerves (roughly C6-C7). It is located deep in the ventrolateral neck.
Origin: Transverse processes of lower cervical vertebrae
Insertion: Ventral surface of the first rib
Action: Elevates the first rib; assists inspiration; lateral flexion of the neck
Innervation: Ventral branches of lower cervical spinal nerves (C6-C7)
Isolated injury is uncommon. Relevant in evaluations of respiratory function and neck mobility.
## Overview Thoracic inlet syndrome occurs when tension in the scalene muscles compresses the brachial plexus or vessels passing through the thoracic inlet. It can cause forelimb coldness or swelling
Not a structure of primary practical concern for owners under normal circumstances.
## Overview Thoracic inlet syndrome occurs when tension in the scalene muscles compresses the brachial plexus or vessels passing through the thoracic inlet. It can cause forelimb coldness or swelling, subtle lameness, and sensitivity at the base of the neck. Poorly fitting breast collars or harnesses may contribute. ## Causes Muscle tension or external compression from tack. ## Diagnosis Clinical signs and exclusion of other causes of forelimb lameness or vascular compromise. ## Treatment Correct tack fit, physiotherapy for the scalene muscles, and rest from aggravating work. ## Recovery and Prognosis Good when the compression is relieved. ## Prevention Proper harness and breast-collar fit. Signs include: forelimb coldness or swelling; subtle forelimb lameness; sensitivity at the base of the neck; associated with poorly fitting breast collars or harnesses
Isolated injury is uncommon. Relevant in evaluations of respiratory function and neck mobility.
Not a structure of primary practical concern for owners under normal circumstances.
See the Ventral Scalene on our interactive 3D horse model. Open 3D Model