Interspinous ligaments
Ligamenta interspinalia
Thin membranes filling the gaps between neighbouring spinous processes, from the base to the tip of each process.
At a glance
- English
- Interspinous ligaments
- Latin (TA2)
- Ligamenta interspinalia
- System
- Ligament
- Region
- Neck
- Side
- Single, on the midline
About the interspinous ligaments
The interspinous ligaments are thin sheets of fibrous tissue that join the spinous processes of adjacent vertebrae. Each one fills the space between two neighbouring processes, reaching from the root of the process, where it leaves the lamina, out to its apex. In front each ligament meets the ligamentum flavum, which links the laminae, and behind it merges with the supraspinous ligament running over the tips of the processes.
Their size follows the shape of the spinous processes. In the thoracic region the ligaments are narrow and long, matching the slender, overlapping processes. In the lumbar region they are broader, thicker and roughly four-sided, filling the wide gaps between the large, blade-like lumbar processes. In the neck they are poorly developed and are often counted as a component of the nuchal ligament, the fibrous septum running up the back of the neck.
With the supraspinous ligament and the ligamenta flava they form the posterior ligament complex of the spine. Their main role is to limit flexion: as the back bends forwards, the spinous processes separate and the interspinous fibres tighten. They also help to keep the vertebrae aligned under load.
These ligaments matter in several clinical settings. In a lumbar puncture or epidural injection by the midline approach, the needle passes through skin, the supraspinous ligament, an interspinous ligament and then the ligamentum flavum; bending the patient forwards opens the gaps and eases the way. In flexion-distraction injuries, such as those caused by a lap seat belt in a crash, the posterior ligaments can tear and leave the spine unstable. Interspinous spacers are sometimes placed between processes to relieve narrowing of the lumbar canal.
Attachments and function
- Attaches from
- The upper border and root of each spinous process.
- Attaches to
- The lower border of the spinous process above, from its root to its apex.
- Function
- Limits flexion of the vertebral column and helps keep adjacent vertebrae aligned.
Anthromica
See the interspinous ligaments where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
