Review Question - QID 219406

Intervertebral disc degeneration is characterized by increased matrix metalloproteinase (MMP) activity (Answer 2), which degrades cellular matrices in bone and cartilage. There is a marked uptake in immunopositivity for MMP in degenerative or herniated intervertebral discs.

This patient presents with symptoms of cervical myelopathy associated with severe degenerative cervical spine spondylosis. Histopathological changes at the cellular level characterize degenerative disc disease. Degenerative intervertebral discs have decreased water content, nutritional transport, viable cells, proteoglycans, and pH. They have increased degradative enzymatic activity, including MMP activity, and no change in the overall quantity of collagen content.

Roberts et al. performed a literature review of the histologic and pathologic changes found in the human intervertebral disc. They describe cellular processes in the developing, normal, degenerative, and deformed human spine. Degenerative intervertebral discs demonstrate thinning of the articular end plates and diminished water content within the cartilage and fibrocartilage of the annulus fibrosis. Intervertebral discs in patients with scoliosis often have ectopic calcifications of the cartilaginous end plate.

Haughton performed a literature review of various imaging modalities to characterize disc degeneration, including multiple types of MR sequences and dynamic MRI. T2 weighted imaging sequences demonstrate a loss of water content within intervertebral discs in the aging and degenerative spine.

Figure A presents a sagittal view on an MRI of a severely degenerative cervical spine with multilevel spondylosis with spinal stenosis and myelomalacia.

Incorrect Answers:
Answer 1, 3-5: Degenerative disc disease is characterized by decreased water content, decreased pH, decreased elasticity, and no change in overall collagen content.