Interactive anatomy viewer for the cervical spine and neck — explore C1–C7 vertebrae, brachial plexus, scalene muscles, SCM, suboccipital triangle, and upper trapezius with guided tracing by Aurelia RMT.
Anatomical Regions
Cervical Vertebrae C1–C7 — Atlas (C1), axis (C2), and C3–C7 forming the cervical column; C1–C2 permit the majority of head rotation
Suboccipital Triangle — Rectus capitis posterior major and minor, obliquus capitis superior and inferior; contains vertebral artery and C1 nerve; source of cervicogenic headaches
Scalene Muscles — Anterior, middle, and posterior scalenes; lateral flexors and accessory respiratory muscles; brachial plexus and subclavian artery pass between anterior and middle scalenes
Sternocleidomastoid (SCM) — Major neck flexor and rotator; unilateral action rotates head contralaterally; palpable from mastoid process to sternum and clavicle
Brachial Plexus — Ventral rami of C5–T1; passes through interscalene triangle; provides all motor and sensory innervation to the upper limb
Upper Trapezius — Extends from occiput and C1–C7 spinous processes to clavicle and scapular spine; elevates and upwardly rotates scapula
Levator Scapulae — Connects C1–C4 transverse processes to superior angle of scapula; elevates and downwardly rotates scapula
Frequently Asked Questions
What is the brachial plexus?
The brachial plexus is a network of nerves formed by the ventral rami of spinal nerves C5–T1. It passes between the anterior and middle scalene muscles and provides motor and sensory innervation to the entire upper limb.
What causes neck pain and stiffness?
Neck pain commonly results from muscle strain in the upper trapezius, levator scapulae, or SCM, poor posture, cervical disc degeneration, or facet joint dysfunction. Prolonged forward-head posture is one of the most frequent contributing factors.
What is the suboccipital triangle and why is it clinically important?
The suboccipital triangle is formed by three small muscles at the base of the skull. It contains the vertebral artery and C1 nerve. Tension in these muscles is a common source of cervicogenic headaches.