Thoracic spine region Flashcards
what happens if the thoracic spine increaes
if the thoracic spine increases (kyphotic) then the cervical spine become more ath the xtreme extension- become degenerate
thoracic cage- structure
vertebral column- posteriorly, 12 sets of ribs, intercostal space, costal cartilage- bond anterior ends of ribs to sternum or other CC, sternum
thoracic cage- function- protection
protection of the vital organs from external trauma due to strength and flexibility- heart, ungs liver
thoracic cage- function- muscle attachment
provide muscle attachment on irregular bones of thoracic spine and long bones of ribs and sternum
thoracic cage- function- assist respiration
internal volume of thoracic is altered by action and movement of ribs/diaphragm increase the AP, vertical and lateral dimensions to draw air in, and increase intrathoracic pressure to expel air
thoracic spinal column
12 thoracic vertebrae, 12 pairs of ribs, sternum
typical thoracic vertebra- characteristics
body, pedicles- 2X- create articular pilar, vertebral foramen, articular process, costal facets, TP, lamina- 2X- blend to form posterior inferior incline and slender SP
typical thoracic vertebra- costal facets
2 demi facets take articulation for ribs, articulare aspect of tubercle of ribs with transverse costal facets- synovial plane
atypical vertebra
T1- articulates with a single facet f it own ribs, has costotransverse facet on its own TP T10/11- lack inferior demifacets on their bodies, T11/12- lack transverse costal facets, articulating only with heads of their own ribs
thoracic vertebra rule of 3
T1,2,3- SP and TP equal T4,5,6- TP 1/2 level above SP T7,8,9,10- TP 1 level above TP T11- TP 1/2 level above SP T12- SP and TP equal
ribs
true ribs- upper 7 ribs articulate via CC with sternum false ribs- remaining 5 ribs- no direct communication with sternum
floating ribs- ribs 11 and 12- CC
costal cartilage
costal cartilage is mobile- has hydroelastic properties- flex in all directions equally, communication of anterior aspect of each rib to sternum via CC, intercostal space between ribs
ribs- joints
coastal cartilaginous joint- primary cartilaginous- no movements at joint, rib 1 sternocostal is primary cartilaginous, ribs 2-7 are synovial plane joints
intercostal joints are synovial plane
typical ribs
ribs 3-9, head-has crest in centre- ligament comes of crest to articulate at intervertebral ribs, neck and shaft, 2 demifacets- articulate as synovial plane facets with articular with demi facets on vertebra above and below, tubercle- posterior tubercle has articular area- TP of own vertebra, adn non articular process- just lateral= posterior angle where it wraps around thoracic, costochondral junction- PC joint- synchondrosis
first rib
has standard head with articular facet- single facet with T1, has anterior aspect of ribs- synchondrosis- PC- with cartilage which blends to sternum via PC joint, has marking for insertions of anterior and middle scalene muscles, between this si the exit for brachial plexus, marking for subclavian vein/ artery superior aspect
ribs 1,2, 10-12
rib 1- slopes inferiorly attach to manubrium, contains the scalene tubercle and 2 seperate grooves (rib 2 is the same but twice as long), ribs 11-12- floating ribs, small facets for articulation for vertebra, no. costotransverse articulation tubercle,, have free standing ends- no CC
intercostal space- contents
space between ribs, contents- intercostal arteries, veins, nerve
intercostal space- muscles
external intercostal, internal intercostal, innermost intercostal, fibres run at 90° to each other- helps to change internal diameters of cage to effect intrathoracic pressure for respiration
spinal nerves of thoracic vertebra
spinal canal very narrow in thoracic spine- as vertebral body gets larger- implication for spinal cord injuries with spinal fractures in this area
thoracic spinal nerve (ventral ramus) runs in intercostal space
spinal nerves of thoracic vertebra- clinical case note
irritation of thoracic nerve root can produce pain radiating around chest wall is sloping in direction following path of ribs
intercostal nerve
dorsal rami- supply skin and muscles of back
anterior rami- in between innermost and internal intercostal supplying muscles
sternum
manubrium, body, xiphoid process, attachment of ribs- all synovial plane joints from 2-7, sternocostal articulation for first rib
joints of thoracic cage
joints between thoracic vertebra- intervertebral and zygapophyseal, joints between rib and spine- costovertebral and costotransverse, joints between. cartilage and ribs/sternum- costochondral, interchondral, and sternocostal
joints of sternum- sternoclavicular, manubriosternal, xiphisternal
joints between thoracic vertebra
intervertebral disc with hyaline end plate on either aspect- intervertebral joints, facet/ zygapophyseal joint- vertical
joints between ribs and vertebra
costovertebral joint- head of rib and costal facet on vertebral body- synovial plane joints
costotransverse joint- posterior facing tubercle of rib with TP of vertebra- synovial plane
joints between cartilage and ribs
costochondral- between sternal end of rib and CC- PC joint interchondral joint- between the CC of last few ribs- synovial plane
joints of sternum
sternocostal joints- ribs 1+ manubrium is PC joint, synovial plane joints between ribs 2-7 and sternum
xiphisternal joint- symphysis- ossifies as we age
movements of thoracic spine
relatively less mobile than cervical and lumbar spine, rotation greatest range, flexion and lateral flexion more restricted
movements of thoracic spine ROM and limiting factor- flexion
20-45, limited by orientation of facet joints, PLL and supra-spinous and interspinous
movements of thoracic spine ROM and limiting factor- extension
25-45, orientation of facet joint, ALL, lig flavum
movements of thoracic spine ROM and limiting factor- rotation
30-35, lig flavum
movements of thoracic spine ROM and limiting factor-side flex
20-40, inter transverse, orientation of facet joints
spinalis thoracis and longismius thoracis origin and insertion
spinalis- SP T11-L2 to SP upper thoracic vertebrae,
longissimus- TP lumbar vertebrae and blends with iliocostalis in lumbar reigion to TP of all thoracic vertebrae
