BACK, SPINE AND SPINAL CORD Flashcards
(51 cards)
anatomical relations of the back
superiorly - the neck
inferiorly - gluteal muscles
UL & LL
The back consists of:
mainly skeletal muscles and bones
functions of the back
- maintenance of posture
- movement of limbs and trunk
surface anatomy of the back - bony landmarks
surface anatomy of the back - muscles
Extrinsic back muscles
function of extrinsic back muscles
- attach back to pectoral girdle
- move UL
innervation of extrinsic muscles
Anterior rami of cervical SN except trapezius which is supplied by the spinal accessory nerve (CN XI)
intrinsic back muscles:
superficial group - erector spinae (spinals, longissimus, iliocostal)
deep group - transversospinalis
function of intrinsic back muscles
move the spine
maintain back posture
name the following muscles and which group of muscles do they belong to?
(L to R) iliocostalis, longissimus, spinalis
belongs to superficial intrinsic muscle group Erector spinae
location of transversospinalis and attachment points of its individual fibres:
location: within the grooves between spinous and transverse processes
attachment points
1. vertebrae to skull
2. vertebrae to a rib
3. vertebrae to another vertebrae
4. vertebrae to the sacrum
Innervation of intrinsic back muscles
segmental nerve supply from the posterior rami of the corresponding SN, i.e, if it is a cervical segment then it would be supplied by the posterior rami of the cervical SN and so on.
label
movements of the spine and the muscles responsible for them
flexion - Psoas major and rectus abdomens
extension - bilateral contraction of erector spinae
lateral flexion - unilateral contraction of erector spinae
number of vertebrae
33 total
7 cervical
12 thoracic
5 lumbar
5 sacral (fused)
4 coccygeal (fused)
functions of the vertebral column
supports head and trunk when upright
protect the SC and the SN
allows movements of the head and neck and trunk
curvatures of the spine and specify whether they are primary or secondary
cervical lordosis (primary)
thoracic kyphosis (secondary)
lumbar lordosis (primary)
Sacral Kyohosis (secondary)
lumbar lordosis increases in certain conditions. name a few conditions and explain the reason.
pregnancy
obesity
certain postures
bc of increased weight bearing
abnormal conditions related to curvatures of the spine
important features of a typical vertebrae and their role
spinous process x 1 (for ligament and muscle attachment)
transverse process x 2 (ligament, muscle and rib articulation)
vertebral arch (pedicle x 2 + lamina x2) (protects te spinal cord)
superior articulate processes x 2 (articulation with adjacent vertebrae)
inferior articulate processes x 2 (articulation with adjacent vertebrae)
vertebral foramen x 1 (contains the spinal cord)
vertebral body x 1 (weight bearing region)
label and give the role
Iv foramen - contains spinal nerves
facet joints - articulation between adjacent vertebrae, can be affected by arthritis
IV discs - articulation between adjacent vertebral bodies
has inner nucleus pulpous and outer annular fibrosus, can herniate
IV discs: location, structure and function
location: between adjacent discs, except between C1 and C2 and the fused sacral and coccygeal segments
structure and function: inner soft nucleus pulpous (upto 90% water in Newborns, degenerates and gets gradually replaced by hard outer annulus fibrosus with age) - flexibility and protection
outer hard annulus fibrosus - provide string bond
each disc allows very small movements, but summation produces larger movement
ligaments of the SC and their attachments/function
Ligamentum flavum: short, connects adjecent lamina
Posterior longitudinal ligament: narrow, weak, weaker support to the IV discs, prevent hyper flexion of the spine
Anterior longitudinal ligament : broad and strong, stronger support to IV discs, prevents hyper extension of spine
supraspinous ligaments: strong and fibrous, connects the tips of the spinous processes
interspinous ligaments: weak, membraneous, connects adjecent spinous processes
