Ribs DSA Flashcards
What does the head of a rib articulate with?
articulates with vertebral body above (inferior costal facet) & with its own vertebra (superior costal facet)
What is the neck of the rib?
area between the head & the tubercle
What does the tubercle of the rib articulate with?
articulates with the transverse process of the corresponding vertebra
What is the angle of the rib?
costal angle is the abrupt change in rib curvature
Name the parts of the typical rib
head neck tubercle angle body
Describe the costochondral joint
between rib & its costal cartilage
Describe the sternocostal joint
between the costal cartilage & body of the sternum
Why are ribs 1, 10, 11, and 12 atypical?
only articulate with their own vertebrae
Ribs 11 & 12
do NOT have tubercles (do not articulate w/ transverse processes)
Which ribs are typical?
ribs 3-9
True ribs
ribs 1-7
cartilage attaches to sternum
False ribs
ribs 8-12
8-10 have cartilage that attach to costal cartilage of rib above
Floating ribs
ribs 11-12
no anterior attachment
Parts of the sternum
Manubrium
Sternal Angle (rib 2 costal cartilage)
Body
Xiphoid process
Action of external intercostal ms
elevate ribs during forced inspiration
starts from spine around to costal cartilage
Action of internal & innermost intercostal ms
depression of ribs
internal: starts from rib angle to sternum
innermost: starts from rib angle to costal cartilage
Anterior Scalene M
inserts on superior surface of 1st rib
elevates 1st rib
Middle Scalene M
inserts on superior surface of 1st rib
elevates 1st rib
Posterior Scalene M
inserts on 2nd rib
elevates 2nd rib
Pectoralis minor m
O: anterior superior surface of ribs 3, 4, 5
I: coracoid process of scapula
stabilizes scapula by drawing it inferiorly & anteriorly
Serratus anterior m
O: ant surface of medial border of scapula
I: superior lateral surface of ribs 2-8
protracts the scapula
Lattissimus dorsi m
O: SP of T7-S3, lower 4 ribs
I: intertubercular groove of humerus
extends & adducts & medially rotates humerus
Quadratus lumborum m
O: iliac crest & iliolumbar ligament
I: inferior aspect of rib 12
extends & laterally flexes vertebral column
**fixes the 12th rib in inhalation
Where does the neurovascular bundle of ribs run?
along costal groove on inferior side of rib
found between internal & innermost intercostal m
Rib Motion Axes
Bucket handle: anterior to posterior
Pump handle: transverse
Bucket handle
ribs move superiorly & laterally
increase transverse diameter
ribs 1-2, 8-10
Pump handle
ribs move superiorly & anteriorly
increase AP diameter
ribs 3-7
Respiratory motion
downward & posterior w/ inhalation
upward & superior w/ exhalation
by ribs 11 & 12
Torsional movement
when T5 is rotated to the right (on T6)-due to rotation of thoracic spine
post aspect of right 6th rib turns externally
post aspect of left 6th rib turns internally
ant extremity of right 6th rib becomes more flat
ant extremity of left 6th rib having its superior margin accentuated
Non-physiologic movement
due to trauma or repetitive micro-trauma
rib becomes subluxed anteriorly or posteriorly
1 or more ribs lose usual plasticity & become restricted in deformed state
Respiratory rib dysfunction
inhalation restriction
exhalation restriction
rib is unable to move in its normal physiologic motion
Structural rib dysfunction
anterior or posterior subluxation superior subluxation of 1st rib anteroposterior compression lateral compression torsion
Inhalation SD
rib being held in position of inhalation such that motion toward inhalation is more free & motion toward exhalation is restricted
Exhalation SD
rib being held in position of exhalation such that motion toward exhalation is more free & motion toward inhalation is restricted
What is the key rib?
rib that maintains a group of ribs in dysfunctional motion
treat this rib first!
Key rib in inhalation SD
bottom of group is key rib
Key rib in exhalation SD
top of group is key rib
How to diagnose inhalation SD
key rib is @ bottom of group
assessment made as to whether pump handle or bucket handle component is most restricted
How to diagnose exhalation SD
key rib is @ top of group
assess if pump handle or bucket handle component is more restricted
Causes of rib dysfunction
Thoracic scoliosis
Rib cage asymmetries (pectus excavatum or pectus carinatum)
Bony diseases
Increased chest wall diameter b/c illness
Abnormal tensions in cervical, rotator cuff or should m
Trauma to rib cage
Lifestyle & affective states
Osteoporosis/OA presentation
ribs become anteriorly depressed b/c deterioration of vertebral support
