Thoracic Skeleton Flashcards
3 parts of sternum
Manubrium
Body
Xiphoid process
Manubrium: upper + lateral margins
Upper = clavicular + jugular notches Lat. = attachment site 1st rib + demifacet half 2nd rib
Body of sternum: upper + lateral margins
Upper = sternal angle Lat. = demifacet + articular facets 3rd-7th ribs
True ribs
1-7
Directly, sternum
Vertebrosternal
False ribs
8-10
Indirectly, cartilages above
Vertebrochondral
Floating ribs
10 + 11
Don’t articulate
Ribs: articulation points
Ant. = sternum Post. = vertebral column (thoracic)
Typical ribs: numbers + parts
3-9
Head, neck, tubercle + shaft
Typical ribs: head
Inf. + sup. facet = sep. by crest
Sup. = above
Inf. same number
Typical ribs: neck
Ant. = smooth Post. = rough
Typical ribs: tubercle
Junction head + neck
Medial = round facet - transverse process, same number
Lateral = rough area - costotransverse ligament
Typical ribs: shaft
Ext. = rough + int. = smooth Costal groove Sternal end = indentation Angle = where curves meet Axis = bent, vertebral = higher
1st rib
Broadest + shortest Atypical Manubrium Head = round, 1 facet for T1 Shaft = single curve, no angles Sup. surface: *groove subclavian a. (post.) + vein (ant.) *scalene tubercle - ant. scalene *middle scalene = btw. tubercle + subcalvian a. *origin serratus ant. *subclavius = distal end
2nd rib
Atypical Sternal angle SIngle curve, no bends Head = 2 facets - T1 + T2 Post. scalene = distal to angle (sup.) Serratus ant. 1st + 2nd digitation = distal to post. scalene
Typical vertebrae: parts
Body
Arch
7 processes
Typical vertebrae: body
Cylindrical, ant. part
Strength to column + supports weight
Typical vertebrae: arch
Post. body
2 pedicles + laminae
Pedicles = short processes, post. from body - meet broad plates = laminae
Arch + post. surface of body = walls of foramen
Succession of foramen = vertebral canal
Notches = indentatins in lat. view - with IV discs, form IV foramina
Typical vertebrae: processes
From arch
1 spinous = post., laminae fuse
2 transverse = lat., laminae + pedicles fuse
2 sup. + 2 inf. = where pedicles + laminae fuse
Sup. - inf. above
Inf. - sup. below
Clavicle: location
Manubrium to scapula
Subcutaneously
Clavicle: medial 2 thirds
Convex ant.
Sternal facet
Costoclavicular tuberosity
Subclavian groove
Clavicle: lateral third
Concave ant. Flattened Acromial facet Conoid tubercle Trapezoid line
Clavicle: joints
Costoclavicular
Acromioclavicular
Coracoclavicular = coracoid process + conoid tubercle, conoid ligament + trapezoid ligament
Thoracic inlet: borders
Lat. = 1st rib Ant. = manubrium Post. = T1
Thoracic outlet: borders
Lat. = ends of rib 11 + 12 Ant. = costal margin + xiphisternal joint Post. = T12
Joints of thoracic wall
Costovertebral = ribs + vertebrae Costotransverse = facet of rib + transverse process, synovial Costochondral = cartilage + ribs Sternochondral/sternocostal = sternum + cartilage
Movement of thoracic wall
Bucket handle:
- lateral/transverse
- ribs = lower lat.
- IC m. contract - elevate ribs
- middle of shaft = lower than 2 ends, when elevated - move laterally
Water pump:
- antero-posterior
- ribs = lower ant.
- IC m. contract - elevate ribs + attached sternum
- sternum = upwards + forward/downwards + backward
Counting ribs
1st = masked
Sternal angle
Move fingers + palpate 2nd rib
Count from here
Why can’t we palpate 1st, 11th + 12th ribs?
1st = masked by clavicle Floating = not ant. attached + protected by erector spinae muscles
