· symphysis (secondary cartilagenous joint)
· upper and lower surfaces of vertebral body covered by thin plate of hyaline cartilage
· plates united by annulus fibrosus
· contains nucleus pulposus
Anterior
· extends
· from anterior tubercle of atlas
· to front of upper part of sacrum
· widens as passes down
· firmly united to periosteum of bodies
· less firmly attached to discs
Posterior
· extends
· from back of axis
· to upper part of sacral canal
· narrows as passes down
· serrated margins
· wide over discs where firmly attached
· narrow over bodies where loosely attached
· continued above atlas as tectorial membrane
· synovial
· capsule blends medially with ligamentum flavum
· nerve supply from two nerves
· from level above and level below
· means one nerve supplies 2 joints
· yellowish from elastin content
· join contiguous borders of adjacent laminae
· attaches to
· front of upper lamina
· back of lower lamina
· antigravity effect
· stretched during flexion
Supraspinous
· join tips of adjacent spinous processes
· strong bands of white tissue
· replaced in neck by ligamentum nuchae
Interspinous
· join adjacent borders of spinous processes
· weak sheets of fibrous tissue
· well-developed in lumbar region
Intertransverse
· join adjacent borders of transverse processes
· weak sheets of fibrous tissue
· synovial joint
· spheroid in shape (egg on side)
· between
· convex occipital condyle
· concave facet on lateral mass of axis
· capsule innervated by C1
· joint allows
· significant flexion-extension
· some lateral flexion
· no rotation
Atlanto-occipital membrane
· attached to
· upper borders of atlas
· outer margins of foramen magnum
· close space between AO joints
· perforated posteriorly by
· vertebral artery
· C1
Median
· small synovial joint
· where dens articulates with back of anterior arch of atlas
Lateral
· larger synovial joint
· between inferior facet of atlas and superior facet of axis
· capsule supplied by C2
Tectorial membrane
· extends upwards in continuity with PLL
· attached to
· back of body of axis
· anterior margin of foramen magnum
· lies in front of spinal cord
· attached to dura
Cruciform ligament
· lies in contact with
· front of tectorial membrane
· back of dens (separated by bursa)
· holds dens in position
· consists of transverse and longitudinal bands
· transverse band
· strong
· attached to tubercle on each side of medial aspect of lateral mass of atlas
· longitudinal band
· weak
· attaches body of atlas to foramen magnum
Apical ligament
· lies in front of longitudinal band of cruciform ligament
· attaches apex of dens to anterior margin of foramen magnum
· fibrous remnant of notochord
Alar ligaments
· lie obliquely on either side of apical ligament
· lie behind atlanto-occipital membrane
· attach margins of dens to margins of foramen magnum
· at front of vertebral column
· longus capitis
· longus colli
· psoas
· in anterior body wall
· rectus abdominus
· discussed elsewhere
· supplied segmentally by posterior rami
· shortest
Interspinales
· join adjacent borders of spinous processes
Intertransversales
· join adjacent borders of transverse processes
· run from transverse processes to spines
Rotatores
· thoracic spine only
· extend
· from base of transverse process
· root of spinous process 1 above
· fibres horizontal
Multifidus
· C2 to sacrum
· extend
· from lamina, mamillary process or transverse process
· to spinous process 2 or 3 above
Semispinalis
· skull to lower thoracic
· lies on multifidus
· extend
· from transverse process
· to spinous process
Thoracis
· from lower thoracic vertebrae
· to spinous process 6 above
Cervicis
· from upper thoracic and cervical vertebra
· to concavity of bifid spinous process of cervical vertebra
Capitis
· large
· chief extensor of head
· covers cervicis
· from upper 6 thoracic and lower 4 cervical
· into occipital bone
· between superior and inferior nuchal lines
· vessels
· ascending branch of superficial cervical artery behind
· deep cervical artery in front
· longest
· fibres
· originate caudally
· insert cephalad
· arise from same spot
· insert further cephalad etc.
Iliocostalis
· lateral
· arise from back of sacrum and inner side of iliac crest
· insert into angles of lower 6 ribs and arise
· insert into angle of 6th rib and arise
· insert into TPs of lower 4 cervical vertebrae
Longissimus
· medial
· arise from back of sacrum and inner side of iliac crest
· insert into gutter between transverse processes and ribs and arise
· thoracis
· insert into TPs of lower 4 cervical vertebrae and arise
· capitis
· insert into mastoid process
· cervicis
· deep to splenius capitis
· covered by splenius
Spinalis
· most medial
· run along spinous processes
· in neck
Origin
· upper 6 thoracic spinous processes
· intervening supraspinous ligaments
· ligamentum nuchae
Path
· slope upwards and laterally
· lie deep to trapezius and sternomastoid
Insertion
· superior nuchal line and mastoid process
· TPs of upper 3 or 4 cervical vertebrae
Nerve supply
· posterior rami
· connect skull to spine and pectoral girdle
· strong band of fibroelastic tissue
· midline intermuscular septum
· triangular in shape
· external occipital crest
· spines of cervical vertebrae
· deep cervical fascia
· lie
· deep to neck muscles
· above C2
· bounded by
· rectus capitis posterior major
· superior oblique
· inferior oblique
· floor
· posterior arch of atlas
· posterior atlanto-occipital membrane
· running across floor
· vertebral artery
· entering through floor
· suboccipital nerve (C1)
· passing across roog
· greater occipital nerve (C2)
· occipital artery
· all supplied by posterior ramus of C1
Rectus capitus posterior major
· origin
· spinous process of C2
· insertion
· lateral part of area below inferior nuchal line
Inferior oblique
· origin
· spinous process of C2
· isertion
· lateral mass of C1
Superior oblique
· origin
· lateral mass of C1
· insertion
· lateral part of area between superior and inferior nuchal lines
Rectus capitus posterior minor
· origin
· posterior arch of atlas
· insertion
· medial part of area below inferior nuchal line
Vertebral artery
· ascends through foraminae in C6 to C1
· anterior to spinal nerves
· gives spinal branch to each intervertebral foramen
· passes laterally with posterior convexity from C2 to C1
· emerges from C1
· passes medially behind atlantooccipital joint
· lies in floor of occipital triangle
· pierces lateral angle of posterior atlanto-occipital membrane
· grooves posterior arch of C1
· enters skull through foramen magnum
Vertebral veins
· start in neck
· form plexus
· descend alongside vertebral artery
· within and without foraminae
· veins emerge
· one from foramen of C6 with vertebral artery
· one from foramen of C7 alone
· join brachiocephalic vein
Suboccipital nerve
· C1
· posterior ramus passes backwards to supply
· two recti
· two obliques
· upper fibres of semispinalis capitis
· anterior ramus winds around lateral part of atlanto-occipital joint to reach cervical plexus
· no cutaneous innervation
Greater occipital nerve
· posterior ramus of C2
· emerges below posterior arch of atlas
· curls around lower margin of inferior oblique
· passes upwards across roof of suboccipital triangle
· pierces and supplies semispinalis capitis
· supplies skin of scalp to vertex
Occipital artery
· runs across roof of suboccipital triangle
· passes to scalp on lateral border of semispinalis capitis
· gives off descending branches that anastomose with ascending branches of cervical and costocervical arteries