Endplate Osteophytic Spurring: Definition and Clinical Significance
Endplate osteophytic spurring refers to the formation of bony outgrowths (osteophytes) at the vertebral endplates that develop as part of the degenerative process of the spine, commonly associated with disc degeneration and often visible on imaging studies.
Anatomy and Pathophysiology
Vertebral endplates are thin layers of cartilage and bone that separate the vertebral bodies from the intervertebral discs. They serve critical functions:
- Provide structural support to the intervertebral disc
- Allow nutrient exchange between the vertebral blood supply and the avascular disc
- Distribute mechanical loads across the spine
When degenerative changes occur, the following processes may develop:
- Formation of osteophytes (bone spurs) at the margins of the vertebral endplates
- Sclerosis (increased bone density) of the endplate
- Progressive narrowing of the disc space
Relationship to Disc Degeneration
Endplate osteophytic spurring is closely associated with other radiographic features of spinal degeneration:
- Research shows a strong association between the presence of osteophytes and endplate sclerosis (β coefficient = 2.7) 1
- A weaker but significant association exists between osteophytes and disc space narrowing (β coefficient = 1.2) 1
- These features typically progress together as part of the degenerative cascade
Types of Osteophytes
Two main morphological types of vertebral osteophytes have been described:
- Claw spurs: More common, hook-shaped projections extending from the vertebral rim
- Traction spurs: Horizontal bony outgrowths
Contrary to previous beliefs, these types frequently coexist on the same vertebral rim, suggesting they may result from the same degenerative process rather than distinct pathological mechanisms 2.
Imaging Findings
Endplate osteophytic spurring can be visualized on various imaging modalities:
- Radiographs: Show bony outgrowths at vertebral margins and endplate sclerosis
- CT: Provides better visualization of osseous structures, showing detailed osteophyte morphology 3
- MRI: Demonstrates associated changes in the disc and impact on neural structures
- Spine MRI findings should be interpreted with specific attention to identify associated morphologic findings such as disc degeneration or osteophytes 3
Clinical Significance
Endplate osteophytic spurring may have several clinical implications:
- Can contribute to spinal canal stenosis and neural foraminal narrowing
- May be associated with back pain, though correlation is variable
- In severe cases, can lead to neurological symptoms if nerve compression occurs
- May complicate surgical approaches to the spine
Relationship to Other Pathologies
Endplate changes can be seen in various conditions:
- Degenerative disc disease
- Spondylosis
- Inflammatory spondyloarthropathies
- Following trauma
- In infectious processes like spondylodiscitis 3
Interesting Research Findings
Contrary to traditional beliefs about endplate sclerosis in degeneration:
- Recent research suggests that vertebral endplate porosity actually increases (by 50-130%) with advancing disc degeneration 4
- Trabecular thickness decreases (by 20-50%) with progressive degeneration 4
- This suggests that endplate sclerosis may not be a fundamental factor contributing to disc degeneration as previously thought
Dynamic Process
Endplate osteophytic spurring represents a dynamic adaptive process:
- Animal studies show that annular injury leads to acute and progressive changes in adjacent vertebral bodies and endplates 5
- These changes include alterations in bone morphology and density
- Osteophyte formation and central physeal ossification can occur relatively early in the degenerative process
In conclusion, endplate osteophytic spurring represents a common radiographic finding in spinal degeneration that correlates with other degenerative changes and may contribute to clinical symptoms through mechanical and neurological effects.