Are There Muscles Between Vertebrae?
No, there are no muscles located directly between the vertebrae or within the intervertebral disc spaces themselves. The intervertebral discs are fibrocartilaginous structures composed of the nucleus pulposus, annulus fibrosus, and cartilaginous endplates—none of which contain muscle tissue 1, 2, 3.
Anatomical Structure of Intervertebral Spaces
The space between adjacent vertebrae is occupied exclusively by the intervertebral disc, which is an avascular structure after skeletal maturity 2. The disc components include:
- Nucleus pulposus: A gelatinous core that provides shock absorption 1, 2
- Annulus fibrosus: Concentric rings of collagen fibers surrounding the nucleus 2
- Cartilaginous endplates: Interface between disc and vertebral body 1, 2
These structures contain no muscle fibers whatsoever 1, 2, 3.
Muscles Adjacent to the Spine
While no muscles exist between vertebrae, multiple muscle groups attach to and surround the vertebral column:
- Paraspinal muscles: Run alongside the spine and attach to vertebral processes, providing support and movement 4
- Multijoint muscles: Connect across multiple vertebral levels to generate spinal motion 5
- Deep spinal muscles: Attach to spinous and transverse processes but do not penetrate the intervertebral disc space 6
These muscles create forces that load the spine and intervertebral discs during movement, but they remain external to the disc structure itself 5, 6.
Clinical Relevance
Understanding this anatomy is critical because:
- Disc degeneration involves breakdown of the disc's fibrocartilaginous components, not muscle tissue 1, 2
- Imaging interpretation of the spine must distinguish between paraspinal muscle pathology and disc pathology 4, 7
- Spinal loading occurs through compression and shear forces transmitted through the disc, with muscles acting as external force generators 5, 6
The intervertebral disc space remains a muscle-free zone throughout life, containing only specialized connective tissue structures designed for load-bearing and shock absorption 1, 2, 3.