15. Vertebral Column and Muscles of the Back Flashcards
Name some functions of the vertebral column (5)
- Muscle attachment
- Mobility
3, Protection - Weight transfer
- Haematopoiesis
What are the primary and secondary curvatures of the vertebral column?
Primary - flexed foetal position
Secondary - extension
What are the regions of the vertebral column? How many vertebrae are in each region?
Cervical - 7 Thoracic - 12 Lumbar - 5 Sacral - 5 Coccyx - 4
What are the 4 principal curvatures of the vertebral column?
Cervical lordosis
Thoracic kyphosis
Lumbar lordosis
Sacral kyphosis
Which 2 bony features create the vertebral arch?
Pedicle and lamina
What are the 7 bony processes on a vertebra?
1x spinous process
2x transverse process
4x articular process
Describe some features unique to C1 (atlas)
No body
No spinous processes
Anterior and posterior arches, each with a tubercle
What articulates with the superior articular surfaces of the C1 vertebra?
Occipital condyles
Describe some features unique to C2 (axis)
Dens/ odontoid process (essentially the ‘missing’ body of C1)
Where on a cervical vertebra (C3-C7) is the uncinate process found?
Body of vertebra
What structures pass through the foramen transversarium of C3-C7 vertebrae?
Vertebral artery
Vertebral vein
Describe the spinous process of a C3-C7 vertebra
Bifid spine
Splits in 2
What structure articulates with the costal facets of the thoracic vertebra?
Ribs
Transverse costal facet - tubercle of rib
Inferior and superior costal facets - head of rib
Describe the spinous process of a T1-T12 vertebra
Long and sloping
Describe some features unique to the lumbar vertebrae
Huge body
Accessory process on the transverse processes
Mammillary processes on each superior articular process
What are the 3 crests found on the sacrum?
Median (=spinous processes)
Intermediate (=articular processes)
Lateral (=transverse processes)
What are the coccygeal cornu?
Bony projections that articulate with the sacrum
What type of joint is the IV disc?
Secondary cartilagenous
Where is the zygapophysial joint?
Between inferior and superior articular processes
What type of joint is the zygapophysial joint?
Plane synovial
What are the superficial extrinsic muscles of the back? (5)
Trapezius
Lat dorsi
Rhomboid major and minor
Levator scapulae
Origin of trapezius?
Medial 1/3rd superior nuchal line
Nuchal ligament
Spinous processes C7-T12
Insertion of trapezius?
Lateral clavicle
Acromion
Spine of scapula
Innervation of trapezius?
Motor - spinal accessory CNXI
Origin of lat dorsi?
Spinous processes T7-12,
Thoracolumbar fascia
Iliac crest
Lower 3/4 ribs
Insertion of lat dorsi?
Edge of bicipital groove of humerus
Innervation of lat dorsi?
Thoracodorsal nerve C6-C8
Origin of rhomboid major?
Spinous processes T2-5
Insertion of rhomboid major?
Medial border of scapula from the spine to inferior angle
Origin of rhomboid minor?
Nuchal ligament
Spinous processes C7, T1
Insertion of rhomboid minor?
Medial end of scapular spine
Innervation of rhomboid minor?
Dorsal scapular nerve C4, C5
Origin of levator scapulae?
Posterior tubercles of transverse processes of C1-C4
Insertion of levator scapulae?
Medial border of scapula above spine
Innervation of levator scapulae?
C3, C4
Dorsal scapular nerve C4, C5
What are the intermediate extrinsic muscles of the back? (2)
Serratus posterior superior
Serratus posterior inferior
Origin of serratus posterior superior?
Nuchal ligament
Spinous processes C7-T3
Insertion of serratus posterior superior?
Superior borders of ribs 2-4
Innervation of serratus posterior superior?
Intercostal nerves 2-5
Origin of serratus posterior inferior?
Spinous processes T11-L2
Insertion of serratus posterior inferior?
Inferior borders of ribs 8-12 near angle
Innervation of serratus posterior inferior?
Anterior rami T9-T12
What are the overall functions of the extrinsic muscles of the back?
Superficial - connect to appendicular skeleton
Intermediate - superficial respiratory muscles
What are the overall functions of the intrinsic muscles of the back? (i.e. the muscles of the back ‘proper’)
Maintain posture
Control movements of vertebral column
What are the 3 layers of the intrinsic muscles of the back?
Superficial - splenius muscles
Intermediate - erector spinae group
Deep - lots of small muscles
What are the 2 superficial intrinsic back muscles?
Splenius capitis
Splenius cervicis
Origin of splenius capitis?
Nuchal ligament
Spinous processes C7-T3/4
Insertion of splenius capitis?
Mastoid process
Lateral 1/3rd superior nuchal line
Origin of splenius cervicis?
Nuchal ligament
Spinous processes C7-T3/4
Insertion of splenius cervicis?
Tubercles of transverse processes C1-C3/4
What are the 3 erector spinae muscles?
Medial - spinalis
Longissimus
Lateral - iliocostalis
What are the common proximal origins of the erector spinae group?
Posterior iliac crest
Posterior sacrum and sacroiliac ligaments
Superior processes of sacral and lower lumbar vertebrae
Supraspinous ligament
What are the 3 parts of the iliocostalis muscle?
Lumborum
Thoracis
Cervicis
What are the 3 parts of longissimus?
Thoracis
Cervicis
Capitis
What are the 3 parts of spinalis?
Thoracis
Cervicis
Capitis
What are the deep intrinsic muscles of the back? (6)
Semispinalis Multifidus Rotatores Levator costarum Interspinale Intertransversari
What are the 3 parts of semispinalis?
Thoracis
Cervicis
Capitis
Origin of semispinalis?
Transverse processes C4-T12
Insertion of semispinalis?
Occipital bone
Thoracic and cervical spinous processes
In which vertebral region is multifidus thickest?
Lumbar region
Describe the orientation and insertion of the multifidis muscle fibres?
Superomedial
To spinous processes 2-4 vertebrae above
In which vertebral region is rotatores thickest?
Thoracic region
Describe the orientation and insertion of the rotatores muscle
Superomedial
To junction of lamina and transverse process 1 or 2 vertebrae above
In which vertebral region is levator costarum found?
Thoracic region
In which vertebral region is interspinale most developed?
Cervical
Lumbar
In which vertebral region is intertransversarii most developed?
Cervical
Lumbar
Innervation of the intrinsic back muscles?
Posterior rami of spinal nerves