Thoracic wall

joints

Heads of ribs

· head of rib has 2 articular facets

· each makes synovial joint with demifacet of vertebral body

· upper facet on rib with lower costal facet on vertebra above

· lower facet on rib with upper costal facet on own vertebra

· ribs of T1, T11 and T12 articulate only with their own vertebrae

· ridge between facets attached to intervertebral disc

Radiate ligaent

· reinforces front of capsule of synovial joints

· upper band to vertebral body above

· lower band to vertebral body below

· middle band to IV disc

· blends with fibres from other side

· remnant of hypochordal bow

Costotransverse

· tubercle of rib has 2 facets

· medial facet forms synovial joint with facet near tip of TP of own vertebra

· exception is T11 and T12

· lower facet nonarticular

Costotransverse ligaments

· reinforce joints

· lateral from lateral nonarticular facet to tip of TP

· middle from back of neck of rib to back of neck of rib

· superior from neck of rib to undersurface of TP above

Costochondral

· between rib and costal cartilage

· primary cartilagenous joint

Interchondral

· between costal cartilages of 6-7, 7-8 and 8-9

· synovial joints

Sternochondral

· between costal cartilages and sternum

· 1st joint

· joins manubrium

· is primary cartilagenous joint

· 2nd joint

· forms 2 synovial joints

· 1 with manubrium and 1 with body

· 3rd-6th joints

· each forms single synovial joint with body

Manubriosternal

· between manubrium and body of sternum

· symphysis

· surfaces covered with hyaline cartilage

· intervening fibrocartilage

· may be cavitation in disc

ribs

Typical

· slopes down at45^o

· angle is most posterior part of rib

Head

· 2 articular facets

· upper and lower

· intervening ridge

· head projects forward

· radiate ligament attached here

Neck

· curved

· upper border curves into crest

· superior costotransverse ligament attached here

· costotransverse lgiament attached to back of neck

Tubercle

· on posteroinferior part

· 2 facets

· medial forms synovial joint with TP

· lateral attaches lateral costotransverse ligament

Shaft

· slopes down and back to angle

· vertical ridge at angle

· then twists forwards

· lower border forms costal groove

1st rib

Head

· small

· single facet for T1

· contacted anteriorly by

· sympathetic trunk (medially)

· supreme intercostal vein & superior intercostal artery (laterally)

Neck

· slopes upward

· contacted by anterior rami of

· C8 (above)

· T1 (below)

Tubercle

· fusion of tubercle and anlge

· cylindrical facet for TP of T1

Shaft

· upper surface has subclavian groove

· occupied by lower trunk of brachial plexus

· subclavian artery lies between trunk and scalenius anterior but only contacts outer border of rib

· scalenius medius attached between groove and tubercle

· inner border of groove projected into scalene tubercle

· for scalenius anterior

· second groove more medially

· for subclavian vein

· anterior surface expands for costal cartilage

· subclavius attached to upper surface of junction

· costoclavicular ligament attached to costal cartilage

12th rib

· head single facet for T12

· no neck, tubercle, angle or costal groove

· attaches

· QL (medial part of lower border)

· anterior and middle lamellae of lumbar fascia

· lateral arcuate ligament

· internal oblique