| Multifidus muscle | |
|---|---|
 Deep muscles of the back. (Multifidus shaded in red.) | |
 Sacrum, dorsal surface. (Multifidus attachment outlined in red.) | |
| Details | |
| Origin | Sacrum,erector spinaeaponeurosis,PSIS, andiliac crest |
| Insertion | Spinous process |
| Nerve | Posterior branches |
| Actions | Provides proprioceptive feedback and input due to high muscle spindle density; Bilateral backward extension, unilateral ipsilateral side-bending and contralateral rotation. |
| Identifiers | |
| Latin | musculus multifidus spinae |
| TA98 | A04.3.02.202 |
| TA2 | 2276 |
| FMA | 22827 |
| Anatomical terms of muscle | |
Themultifidus (multifidus spinae;pl.:multifidi)muscle consists of a number of fleshy and tendinousfasciculi, which fill up the groove on either side of thespinous processes of thevertebrae, from thesacrum to theaxis. While very thin, the multifidus muscle plays an important role in stabilizing the joints within the spine. The multifidus is one of thetransversospinales.
Located just superficially to the spine itself, the multifidus muscle spans three joint segments and works to stabilize these joints at each level.
The stiffness and stability makes eachvertebra work more effectively, and reduces the degeneration of the joint structures caused by friction from normal physical activity.
These fasciculi arise:
Each fasciculus, passing obliquely upward and medially, is inserted into the whole length of thespinous process of one of the vertebræ above.
These fasciculi vary in length: the most superficial, the longest, pass from one vertebra to the third or fourth above; those next in order run from one vertebra to the second or third above; while the deepest connect two adjacent vertebrae.
The multifidus lies deep relative to thespinal erectors,transverse abdominis,abdominal internal oblique muscle andabdominal external oblique muscle.
Dysfunction in the lumbar multifidus muscles is strongly associated withlow back pain. The dysfunction can be caused by inhibition of pain by the spine. The dysfunction frequently persists even after the pain has disappeared. Such persistence may help explain the high recurrence rates of low back pain. Persistent lumbar multifidus dysfunction is diagnosed byatrophic replacement of the multifidus with fat, as visualized bymagnetic resonance imaging orultrasound.[1][2] One way to help recruit and strengthen the lumbar multifidus muscles is by tensing thepelvic floor muscles for a few seconds "as if stopping urination midstream".[3]
This article incorporates text in thepublic domain frompage 400 of the 20th edition ofGray's Anatomy(1918)
