Rectus capitis posterior minor is the smallest suboccipital muscle, connecting the C1 posterior arch to the occipital bone. Its myodural connections to the atlanto-occipital membrane and spinal dura are the most direct of all suboccipital muscles.
| Origin | Posterior arch of the atlas — posterior tubercle |
|---|---|
| Insertion | Inferior nuchal line — medial portion |
| Nerve Supply | Suboccipital nerve — dorsal ramus of C1 |
| Blood Supply | Vertebral artery muscular branches |
| Actions | Extends the head at the atlantooccipital joint — minor contribution; Tenses the posterior atlanto-occipital membrane |
|---|
Rectus capitis posterior minor has the most consistent and strongest myodural bridge to the posterior atlanto-occipital membrane and cervical dura. Its atrophy (seen in many headache sufferers) correlates with reduced tensioning of the dura — some researchers propose this as a headache mechanism. It is selectively atrophied before other suboccipital muscles in chronic headache patients.
Not individually palpable.
Selective rectus capitis posterior minor fatty infiltration on MRI in chronic headache patients, associated with myodural bridge dysfunction and altered dural tension.
