Rectus Capitis Posterior Minor Detail

musculus rectus capitis posterior minor detail

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.

Nerve: Suboccipital nerve — dorsal ramus of C1 Blood Supply: Vertebral artery muscular branches Region: Neck

Anatomical Data

Origin, Insertion & Supply

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

Biomechanics

Function & Actions

Actions	Extends the head at the atlantooccipital joint — minor contribution; Tenses the posterior atlanto-occipital membrane

Clinical Relevance

Clinical Notes

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.

Palpation

Not individually palpable.

Pathology

Common Injuries & Conditions

Rectus Capitis Posterior Minor Atrophy in Chronic Headache

Selective rectus capitis posterior minor fatty infiltration on MRI in chronic headache patients, associated with myodural bridge dysfunction and altered dural tension.