C7 nerve root !

The C7 nerve root leaves the spine at C6-C7; it powers the triceps and wrist flexors and gives feeling to the middle finger.

Official name: C7

See in 3D →

Opens in the Durgical app, no sign-up needed.

What it is

The C7 nerve root, leaving the spine at C6-C7, the most commonly pinched neck root.

What it does

Supplies the triceps and wrist flexors, the triceps reflex, and feeling in the middle finger.

Key facts

Roots: C7 dorsal and ventral roots; exits the C6–C7 intervertebral foramen; most often compressed cervical root (C6–C7 disc)
Moves: Triceps, wrist flexors, finger extensors; triceps reflex (C7; some texts: C7–C8)
Feeling from: Middle finger (varies: index and ring sides)

Relations

Course: Leaves the C6–C7 foramen behind the vertebral artery and continues on its own as the middle trunk of the brachial plexus, between the scalenes
In front: The C6–C7 disc and uncovertebral joint
Behind: The C6–C7 facet joint

How to find it

It cannot be felt. It leaves through the C6–C7 foramen; on ultrasound the C7 transverse process has a posterior tubercle but little or no anterior one, which tells it from C6, and the vertebral artery is seen just in front of it before entering the C6 foramen.

Examination

Resisted elbow extension (ISNCSCI C7 key muscle); slight weakness shows better when the person pushes up from a chair or does push-ups
Triceps reflex, tapping the tendon above the olecranon with the arm hanging relaxed
Pinprick on the back of the middle finger's proximal phalanx (C7 key point)

On imaging

Leaves through the C6–C7 foramen; axial MRI at that level shows a disc or spur pressing on it, and CT myelography replaces MRI if needed. On ultrasound the C7 transverse process has only a posterior tubercle, with the vertebral artery just in front of the root; this tells C7 from C6 when scanning down the neck. Radiographs show narrowing and spurs at C6–C7.

Common problems

Cervical radiculopathy: a disc or bone spur pinches a root, causing pain, numbness or weakness down the arm in that root's pattern.

How it is diagnosed

Exam of strength, reflexes and feeling in the arm (each root has its own pattern); MRI; sometimes nerve tests (EMG).

Treatment

Most improve with time, physical therapy, medicine and sometimes an injection.
Lasting pain or weakness: surgery to free the root, such as ACDF or a foraminotomy.

Clinical notes

C7 vs radial nerve: a spiral-groove radial palsy gives wrist and finger drop but usually spares triceps, wrist flexion and forearm pronation; C7 weakens triceps, wrist flexion and pronation together
Pain over the inner border of the shoulder blade often comes before the arm symptoms of C7 radiculopathy
In severe brachial plexus avulsion, the healthy side's C7 root can be transferred across to restore some function (contralateral C7 transfer)

Test yourself

Think of the answer, then tap the question to see it.

Which disc herniation compresses the C7 nerve root, the most often affected cervical root?

A C6–C7 disc herniation; the C7 root exits through the C6–C7 foramen.

What are the ISNCSCI key muscle and key sensory point for the C7 nerve root?

Key muscle: elbow extensors (triceps). Key sensory point: back of the middle finger over the proximal phalanx.

Which reflex is reduced in a C7 radiculopathy?

The triceps reflex, along with a weak triceps and pain down the back of the arm to the middle finger.

How is a C7 radiculopathy told apart from a radial nerve palsy at the spiral groove?

C7 weakens triceps, wrist flexion and pronation together; a spiral-groove radial palsy gives wrist and finger drop but usually spares all three.

Add to my cards (4)

Educational information, not medical advice. For any symptom, see a health professional.

Its names

Official Latin (TA2): radix nervi spinalis C7 TA2 6363
Official Spanish (DeCS): Raíz C7 DeCS D013126
English (TA2): C7
Also called: spinal nerves C1-C8

Sources: Terminologia Anatomica (TA2); DeCS; Anatomy, Head and Neck: Cervical Nerves; Anatomy, Skin, Dermatomes.

Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake

Representative model, for educational purposes only.

C7 nerve root highlighted on the Durgical 3D model