Upper limb

Anulus fibrosus of cervical intervertebral discs (C2–T1)

Anulus fibrosus disci intervertebralis (pars cervicalis)

Origin

Concentric lamellae of fibrocartilage and collagen type I anchored to superior vertebral endplate

Insertion

Anchored via Sharpey fibers to inferior vertebral endplate and rim

Function

Retains nucleus pulposus and resists tensile, compressive, and torsional stresses in the cervical spine

Innervation

Sinuvertebral nerves and gray rami communicantes (outer third)

Movement & chain

Elastic deformation during cervical flexion, extension, rotation, and lateral bending

Palpation

Not palpated directly; deep anterior neck structures

Clinical

Annular tears, cervical disc herniation (most common at C5-C6 and C6-C7) causing cervical radiculopathy; treated conservatively or via ACDF surgery.

Segmental innervation

C2–C8

In clinical practice

Cervical traction, postural re-education, and ergonomics in neck pain management

Region in the model

Upper limb