The Back: Bones, Ligaments and Muscles Flashcards
What are the functions of the vertebral column?
Enables upright posture
Supports body weight
Protects and transmits spinal cord and spinal nerves
Supports the skull and allows for its movement
Contributes to the rib cage
Locomotion
What are the two curves of the spinal cord?
Concave- kyphosis- thoracic
Convex- lordosis- lumbar
What are the different structures of the vertebra?
Vertebral body
Intervertebral surface
Vertebral arch- pedicle and lamina
Vertebral foramen
Inferior and superior vertebral notch
What are the junctions between multiple vertebra?
Articular facets
What are found in cervical vertebra?
Uncinate processes
Superior articular facets
Transverse foramen
What is C1 called?
Atlas
How does atlas connect to the skull?
Between its superior articular facets and the skulls occipital condyles
What is C2 called?
Axis
What is significant about axis?
Has odontoid process or dens
At what joint does the head and neck rotate?
Atlanto-axial joint
What are specific to thoracic vertebra?
Transverse processes that are long with a face for articulation with the tubercle of its own rib
Costal demi facets for upper and lower articulation
Spinous processes that overlap 2 vertebrae
What vertebrae have the largest size?
Lumbar
What are specific to lumbar vertebra?
Largest body
Spine is sturdy, stumpy and quadrangular
Extension is greatest movement
What are specific to sacrum?
Sacral promontory is the anterior projection of S!
Median, intermediate and lateral crests
Anterior and posterior foramen
Sacral hiatus
What type of joint is between the vertebral column?
Symphysis or secondary cartilaginous joint
What type of joint is between articular processes?
Zygapophyseal
Facet
Where do spinal nerves emerge?
Intervertebral foramen
What is the intervertebral disc made from?
Nucleus pulposus and anulus fibrosus
Describe the nucleus pulposus
Gelatinous, 70-90% water
Inside
Absorbs compressive forces between vertebrae
Relative collagen content increase with age
Describe the anulus fibrosus
Very strong, concentric lamellae of fibrocartilage
Outside
Attached and kept in place by anterior and posterior longitudinal ligaments
What is a herniated disc?
Nucleus pulposus may herniate or prolapse to compress the spinal cord, cauda equina or spinal nerve
Where do most herniated disc move to?
Posterolateral and compresses on spinal nerve above its vertebrae
What are the different ligaments of the vertebral column?
Anterior Atlanto-Axial and Atlanto- Occipital membranes
Anterior longitudinal ligament from ^
Posterior longitudinal ligament from tectorial membrane
Ligamenta flavum- between lamina
Intertransverse ligaments- between transverse processes
Supraspinous ligaments- between tips of spines
Ligamentum nuchae- extends between external occipital protuberance and posterior edge of foramen magnum
Interspinous ligaments
What are the ligaments of the atlas and axis?
Alar ligaments- from sides of dens to foramen magnum
Transverse ligaments
Longitudinal ligament
What do the transverse ligament, superior and inferior longitudinal fascicles form?
Cruciate ligament
What are common in the vertebral column and why?
Metastasis as there are no valves in the veins
What are the functions of intrinsic back muscles?
Adapted to provide support and movement in resistance to the effect of gravity
Move the vertebral column
Participate in moving head
Innervated by the posterior rami of spinal nerves
What are the functions of the extrinsic back muscles?
Movement of the upper limbs and thoracic wall
Innervated by anterior rami of spinal nerves
What are the attachments of trapezius?
Skull, ligamentum nuchae and spines of C7 to T12 to scapula and clavicle
Function of trapezius
Extends neck, retracts scapular, rotate shoulders in abduction
Innervation of trapezius?
Accessory nerve
Origin and attachments of latissimus dorsi
Iliac crest, fascia, spines of T6-T12, lower ribs
Humerus
Function of latissimus dorsi
Shoulder extensions and adduction
Innervation of latissimus dorsi?
Thoracodorsal nerve
Function of levator scapulae?
Scapular elevation
Function of rhomboid major and minor
Scapular retraction and elevation
Function of serratus posterior superior
Inspiration
Function of serratus posterior inferior
Expiration
What is found in the 1st layer of extrinsic back muscles?
Lat dorsi and trapezius
What is found in the 2nd layer of extrinsic back muscles?
Levator scapulae
Rhomboid major and minor
Serratus posterior superior and inferior
What are the three layers of intrinsic back muscles?
Superficial
Intermediate
Deep
What are muscles in the superficial layer of the intrinsic back muscles?
Splenius capitis and cervicis
What are the functions of Splenius capitis and cervicis?
Extend the neck
Rotate and laterally flex
What muscles are found in the intermediate layer of the intrinsic back muscles?
Iliocostalis
Longissimus
Spinalis
Grouped together as the erector spinae
What muscles form the deep layer of intrinsic back muscles?
Semispinalis
Rotatores
Multifidus
Levators costarum
Interspinous
Intertransverse
What are the deep neck muscles?
Obliques capitis superior
Obliquus capitis inferior
Rectus capitis posterior major
Rectus capitis posterior minor
What is found in the sub-occipital triangle?
Vertebral artery and suboccipital nerve