Suboccipital Triangle Flashcards
Occipital Bone: Actions
Provides a bone surface for insertion of the suboccipital muscles, articulates with the first cervical vertebra which gives attachment to 3 of the suboccipital muscles, contains the foramen magnum through which pass both vetebral arteries
Atlas C1
Superior Articular processes/lateral masses articulate with the occipital condyles
Vertebral foramen lies immediately below the foramen magnum
has no body
has a posterior tubercle instead of a spinous process
Axis
Embrylogical body of the first cervical vertebra fused to it and is called the odontoid process/ dens
Inferior Oblique: Origin and Insertion
Origin: Spine of C2
Insertion: transverse process of C1
Superior Oblique: origin and insertion
Origin: Transverse Process of C1
Inserts: occipital Bone
Rectus Capitis Posterior Minor Muscle: Origin and Insertion
Origin: Posterior Tubercle of C1
Inserts: occipital Bone
Rectus capitis Posterior Major Muscle: Origin and Insertion
Origin: Spinous Process of C2
Insertion: Occipital Bone
Suboccipital Muscles: Innervation
Suboccipital nerve, dorsal/posterior ramus of C1
Suboccipital Muscles: Action
All extend the head and rotate it and the atlas toward the same side
Vertebral Arteries: Passageway
Pass cranially through teh transverse foramen of C6-C1
Pass posteriorly and medially to the superior articular process of C1 lying in a groove on the lamina
turns anteriorly and superiorly to pass through the foramen magnum into the skull
Dorsal/Posterior Primary Ramus of C1/Suboccipital nerve
Emerges within the triangle between the vertebral artery and the lamina of the C1 vertebra, and then distributes to innervate all the suboccipital muscles
Ventral/anterior primary ramus
continues laterally to pass immediately posterior to the vertebral artery as it leaves the transverse foramen
Suboccipital Coverings
Suboc triangle is covered posteriorly and inferiorly by the semispinalis capitis muscles, splenius capitis and trapezius muscles
