Cervical Disc Disease

Cervical disc disorders encountered in physiatric practice include   (HNP),  (DDD), and internal disc disruption (IDD). HNP (seen in the image below) is defined as localized displacement of nucleus, cartilage, fragmented apophyseal bone, or fragmented anular tissue beyond the intervertebral disc space.^[1] Most of the herniation is made up of the annulus fibrosus. DDD involves degenerative annular tears, loss of disc height, and nuclear degradation. IDD describes annular fissuring of the disc without external disc deformation. can result from nerve root injury in the presence of disc herniation or stenosis, most commonly foraminal , leading to sensory, motor, or reflex abnormalities in the affected nerve root distribution.^{[2, 3]}
Sagittal magnetic resonance imaging (MRI) scan demonstrating cervical intervertebral disc protrusions at C3-C4 and C7-T1. Understanding  requires basic knowledge of anatomy and biomechanics. The intervertebral disc is a functional unit connecting 2 vertebral bodies of the spine. The disc absorbs shock, accommodates movement, provides support, and separates vertebral bodies to lend height to intervertebral foramina. The disc consists of 3 structural components; an eccentrically located nucleus pulposus, a surrounding lamellar annulus fibrosus, and 2 cartilaginous endplates, separating each segmental level between the C2-T1 vertebrae. No disc exists between C1 and C2, and only ligaments and joint capsules resist excessive motion. Disc degeneration and/or herniation can injure the spinal cord or nerve roots and result in