What is Spondylosis?
Spondylosis is a chronic, degenerative disease of the spine caused by age-related deterioration of the intervertebral discs and facet joints, most commonly affecting the cervical and lumbar regions 1, 2.
Pathophysiology
Spondylosis develops through a multifactorial degenerative process that affects the functional units of the spine:
- Disc degeneration: Progressive breakdown of intervertebral disc structure leads to loss of disc height and altered biomechanics 2
- Facet joint arthritis: Degenerative changes in the posterior joints contribute to spinal instability
- Osteophyte formation: Bone spurs develop as a response to abnormal stress distribution, which can narrow the spinal canal and neural foramina 2
- Ligamentous changes: Thickening of spinal ligaments further compromises available space for neural structures
The disc and facets serve as connecting structures between vertebrae for force transmission and mobility facilitation. When these degenerate, mechanical pressure on the spinal cord or nerve roots can occur, producing direct neurological damage or ischemic changes 2.
Clinical Presentations
Spondylosis manifests in three distinct patterns 3:
1. Axial Pain
- Intermittent neck or low back discomfort
- Most common presentation in middle-aged and elderly patients 4
- Usually responds to conservative management
2. Radiculopathy
- Radiating leg or arm pain from nerve root compression
- Results from osteophyte formation narrowing neural foramina
- May include sensory and motor deficits in specific dermatomal distributions
3. Myelopathy
- Most serious and disabling manifestation 4
- Caused by spinal cord compression, typically in patients with congenital spinal stenosis 4
- Presents with decreased hand dexterity, gait instability, and progressive neurologic deficits 5
- Cervical spondylotic myelopathy is the most common form of spinal cord injury in adults 5
Important Clinical Caveat
Not all patients with radiographic evidence of spondylosis are symptomatic 3. Imaging findings of disc degeneration and osteophytes may be present in asymptomatic individuals, making correlation with clinical presentation essential. Neurologic consultation is advised when imaging shows neural structure involvement to rule out other neurologic diseases 4.
Regional Variations
- Cervical spondylosis: Most common progressive disorder in the aging cervical spine 2, often presents with neck pain and may progress to myelopathy
- Lumbar spondylosis: Presents with low back pain, neurogenic claudication (intermittent leg pain with walking), or radiculopathy 1
The condition may be associated with spondylolisthesis (vertebral slippage) or spinal stenosis (canal narrowing), which influence treatment decisions 6, 7.