[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Spine](https://durgical.com/en/anatomy/region/spine/) › C6 nerve root [Nervous system](https://durgical.com/en/anatomy/system/nervous-system/) · [Spine](https://durgical.com/en/anatomy/region/spine/) # C6 nerve root The C6 nerve root leaves the [spine](https://durgical.com/en/anatomy/region/spine/) at C5-C6, the second most often pinched neck root; it gives feeling to the thumb side of the forearm and hand. Official name: C6 [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=spine&select=c6_root&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The C6 nerve root, leaving the spine at C5-C6; after C7, the most commonly pinched neck root. ## What it does Supplies the biceps and wrist extensors, the biceps and brachioradialis reflexes, and feeling in the thumb side of the forearm and hand. ## Key points - ISNCSCI key muscle: wrist extensors; key sensory point: back of the thumb over the proximal phalanx - Compressed by a C5–C6 disc or foraminal spurs: neck pain spreading down the outer arm to the thumb and index finger - Inverted [brachioradialis](https://durgical.com/en/anatomy/brachioradialis/) reflex (tapping brachioradialis flexes the fingers instead) suggests cord compression at C5–C6 as well as root involvement ## Key facts **Roots** C6 dorsal and ventral roots; exits the C5–C6 intervertebral foramen; compressed by a C5–C6 disc herniation **Moves** Biceps, [brachialis](https://durgical.com/en/anatomy/brachialis/), brachioradialis, wrist extensors (extensor carpi radialis); biceps and brachioradialis reflexes (C5–C6) **Feeling from** Lateral forearm, thumb and index finger (varies) ## Relations **Course** Leaves the C5–C6 foramen behind the [vertebral artery](https://durgical.com/en/anatomy/vertebral-artery/) and joins C5 to form the upper trunk of the [brachial plexus](https://durgical.com/en/anatomy/roots-of-brachial-plexus/); it also sends fibres to the [long thoracic nerve](https://durgical.com/en/anatomy/long-thoracic-nerve/) **In front** The [C5–C6 disc](https://durgical.com/en/anatomy/c5-c6/) and uncovertebral joint **Behind** The C5–C6 facet joint ## How to find it It cannot be felt. It leaves through the C5–C6 foramen and lies in the gutter of the C6 transverse process, whose large anterior (carotid) tubercle can be felt deep at the level of the [cricoid cartilage](https://durgical.com/en/anatomy/cricoid-cartilage/); on ultrasound that tubercle identifies the C6 level. ## Examination - Resisted wrist extension ([extensor carpi radialis longus](https://durgical.com/en/anatomy/extensor-carpi-radialis-longus/) and brevis), the ISNCSCI C6 key muscle - Brachioradialis reflex: tapping the radial side of the forearm near the wrist; reduced in C6 radiculopathy - Spurling test reproducing pain into the thumb and index finger - Pinprick on the back of the thumb's proximal phalanx (C6 key point) ## On imaging Leaves through the C5–C6 foramen; axial MRI at that level shows the disc or spur pressing on it. On ultrasound the C6 transverse process has a large anterior tubercle (carotid tubercle) and a smaller posterior one, with the root lying between them; this shape names the level. On MRI a high-signal cord at C5–C6 with an inverted brachioradialis reflex points to myelopathy. ## 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 - C6 vs [carpal tunnel](https://durgical.com/en/anatomy/carpal-tunnel/) syndrome: both numb the thumb and index finger, but C6 brings neck and arm pain, a reduced biceps or brachioradialis reflex and weak elbow flexion or wrist extension; carpal tunnel spares the reflexes and weakens thumb abduction - Both can coexist (double crush); nerve conduction studies show slowing at the wrist in carpal tunnel and are normal in a pure root lesion - In tetraplegia at C6, keeping wrist extension allows a tenodesis grip: extending the wrist passively closes the fingers for useful hand function ## Related conditions - [Cervical radiculopathy](https://durgical.com/en/conditions/cervical-radiculopathy/) - [Cervical Spondylosis](https://durgical.com/en/conditions/cervical-spondylosis/) ## Test yourself Think of the answer, then tap the question to see it. ## Which disc herniation compresses the C6 nerve root, and where does the pain spread? A C5–C6 disc herniation (or foraminal spurs); pain spreads down the outer arm to the thumb and index finger. ## What are the ISNCSCI key muscle and key sensory point for the C6 nerve root? Key muscle: wrist extensors (extensor carpi radialis). Key sensory point: back of the thumb over the proximal phalanx. ## Which reflexes are reduced in a C6 radiculopathy? The biceps and brachioradialis reflexes (C5–C6). ## How is a C6 radiculopathy told apart from carpal tunnel syndrome? C6 adds neck and arm pain, a reduced biceps or brachioradialis reflex and weak elbow flexion or wrist extension; carpal tunnel spares reflexes and weakens thumb abduction. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/c6-spine-and-pelvis/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** radix nervi spinalis C6 TA2 6363 **Official Spanish (DeCS)** Raíz C6 DeCS D013126 **English (TA2)** C6 **Also called** spinal nerves C1-C8 ## Related - [C5–C6 disc](https://durgical.com/en/anatomy/c5-c6/) - [Neck nerve roots](https://durgical.com/en/anatomy/anterior-root-of-spinal-nerve/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=13510&filter=ths_termall&q=Ra%C3%ADces%20Nerviosas%20Espinales); [Anatomy, Head and Neck: Cervical Nerves](https://www.ncbi.nlm.nih.gov/books/NBK538136/); [Anatomy, Skin, Dermatomes](https://www.ncbi.nlm.nih.gov/books/NBK535401/). ## **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. --- Source: https://durgical.com/en/anatomy/c6-spine-and-pelvis/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/c6-spine-and-pelvis/