Intervertebral disk of fifth cervical vertebra: anatomy, location and function

What it is

The intervertebral disc between C5 and C6 (the C5–C6 disc), a fibrocartilage pad with a gel-like nucleus pulposus inside a ring-like anulus fibrosus.

Location

Between the bodies of C5 and C6, the disc directly below the named vertebra (the C5/C6 disc).

Function

Absorbs compressive loads, acts as a shock absorber and allows slight movement between vertebrae.

Body system

Skeletal · single, midline structure

FMA ID

FMA13898 (Foundational Model of Anatomy)

Key facts

• The C6 root exits here; C6 radiculopathy weakens elbow flexion and wrist extension, dulls the brachioradialis reflex and numbs the thumb.
• C5–C6 is the segment of greatest cervical flexion–extension and degenerates early.
• Cervical discs are thicker in front than behind, which helps create the cervical lordosis; uncovertebral joints (of Luschka) flank the cervical discs from C2–C3 to C6–C7.

Clinical relevance

Herniation occurs when the nucleus pulposus pushes through a tear in the annulus. A posterolateral herniation here usually compresses the C6 nerve root. This is one of the two most common cervical levels for herniation.

The nearest named structures in the 3D model, measured from the centre of each part:

• Vertical intermediate part of longus colli · muscular
• Posterior crico-arytenoid · muscular
• Oblique arytenoid · muscular
• Transverse arytenoid · muscular
• Intervertebral disk of sixth cervical vertebra · skeletal
• Intervertebral disk of fourth cervical vertebra · skeletal
• Cricoid cartilage · respiratory
• Arytenoid cartilage · respiratory
• Corniculate cartilage · respiratory
• Oblique part of cricothyroid · muscular