The rectus capitis lateralis muscle is a small muscle located in the neck region. It is one of the extrinsic muscles of the head, meaning that it originates from a location outside the head and neck and acts on the head.
Structure
The rectus capitis lateralis muscle is a long, slender muscle with a tendinous origin and an aponeurotic insertion. It arises from the posterior border of the transverse process of the atlas, the first cervical vertebrae, and runs upwards and medially towards the base of the skull. The muscle then passes through the superior nuchal line of the occipital bone and inserts onto the occipital bone just below the superior nuchal line.
The rectus capitis lateralis muscle is innervated by the suboccipital nerve, which is a branch of the posterior primary rami of the spinal nerves C1-C3. It receives blood supply from the occipital artery.
Location
The rectus capitis lateralis muscle is located in the posterior neck region, just below the base of the skull. It lies deep to the semispinalis capitis muscle and the splenius capitis muscle, and is superficial to the suboccipital muscles.
Function
The main function of the rectus capitis lateralis muscle is to extend and laterally flex the head. It works in conjunction with the other extrinsic muscles of the head, such as the sternocleidomastoid and the splenius capitis, to move the head in different directions.
Clinical Significance
The rectus capitis lateralis muscle can be strained or damaged through activities that involve repeated head movement or sustained awkward head positions. This can lead to muscle spasms, headaches, and neck pain. Treatment may involve rest, ice, physical therapy, and pain management.
In rare cases, the rectus capitis lateralis muscle may be affected by a congenital anomaly, such as a duplication or absence of the muscle. This can lead to abnormalities in head and neck movement and may require surgical intervention.
