Neurovasculature of the back
After completing this study unit you will be able to:
- Identify the main arteries of the back and neck and their branches.
- Describe the venous drainage of the back and neck.
- Name the main nerves of the back and neck.
The back is a region on the posterior surface of the trunk which extends from the inferior border of the neck to the gluteal region. The layers of the back comprise the skin, subcutaneous tissue, superficial and deep back muscles, the posterior portion of the ribs, and the vertebral column housing the spinal cord and surrounding meninges. The back plays an important role in stabilizing and enabling movements of the trunk, upper limbs and head.
The structures of the back are supplied by several important arteries, veins, and nerves. The arterial supply arises from several main sources: directly from the aorta for much of the posterior thorax and abdomen, or via the subclavian arteries in the neck and scapular regions. The veins of the back and neck mainly drain into the brachiocephalic veins, azygos venous system, and inferior vena cava. The nervous supply mainly arises from the cervical, thoracic and lumbar spinal nerves.
Learn more about the neurovascular supply of the back and posterior neck in the video below.
Take a quiz
Solidify your knowledge by taking the following quiz.
For a broader topic focus, try out this fully customizable quiz:
Explore each of the structures you learned about today in the gallery below.
Occipital artery: Origin: External carotid artery, supplies back of scalp,sternocleidomastoid muscles, and deep muscles of back and neck
Deep cervical artery: Origin: Costocervical trunk, supplies deep muscles of neck
Transverse cervical artery: Origin: Thyrocervical, trunk, supplies trapezius and sternocleidomastoid muscles
Posterior intercostal arteries: Origin: Thoracic aorta, supply muscles and skin of the thoracic region
Subcostal artery: Origin: Thoracic aorta, supplies subcostal region
Lumbar arteries: Origin: Abdominal aorta, supply muscles and skin in lumbar region, contents of vertebral canal, and abdominal wall
Occipital vein: Drains to suboccipital venous plexus
Deep cervical vein: Drains to vertebral vein
Vertebral veins: Drains to brachiocephalic vein
Posterior intercostal veins: Drains to azygos venous system
Subcostal vein: Drains to ascending lumbar vein
Lumbar veins: Drain to azygos venous system (via ascending lumbar vein), or inferior vena cava
|Nerves: Muscular innervation||
Superficial (extrinsic) muscles of back: All muscles innervated by branches of cervical/brachial plexus or intercostal nerves except for the trapezius muscle (accessory nerve (CN XI))
Deep (intrinsic) muscles of back: Almost all muscles innervated by posterior rami of cervical/thoracic/lumbar spinal nerves
Suboccipital muscles: Suboccipital nerve (C1)
Cervical region: Posterior rami of spinal nerves C2-C4/5, greater/lesser/third occipital nerves (C2-C3)
Thoracic region: Posterior rami of spinal nerves T2-T12, lateral cutaneous branches of 2nd-11th intercostal nerves/subcostal nerve
Lumbar region: Posterior rami of spinal nerves L1-L2/3