Session 6 Flashcards
Describe how the RC and deltoid work together for dynamic stabilization of the GH joint.
- forces act to keep humeral head compressed into glenoid fossa with dynamic elevation
- force coupling with deltoid
- deltoid alone cannot abduct (elevate) UE.
- need another set of forces to work synergistically with deltoid force and achieve desired rotation (motion of elevation)
- all lines of action contribute to dynamic stabilization of GH joint.
name the 6 motions of the scapula.
- depression/elevation
- protraction/retraction
- upward/downward rotation
inferior angle moves away from vertebral column
upward rotation
inferior angle moves toward vertebral column
downward rotation
Describe scapulohumeral rhythm.
- there is a 2:1 ratio of glenohumeral to scapulothoracic movement during arm elevation.
- first 30 degrees is glenohumeral movement
- scapulothoracic movement contributes 50-60 degrees.
- GH joint contributes 100-120 degrees of flexion and 90-120 degrees of abduction
name 3 purposes of scapulohumeral rhythm.
- mechanical stability
- prevents impingement
- maintains optimal length-tension ratio of deltoid and supraspinatus
what is scapular winging?
excessive scapular internal rotation - causes prominence of the medial border and inferior angle of the scapula with attempted elevation of the arms.
what can cause scapular winging?
loss of serratus anterior (SA muscles anchors the scapula against the rib cage)
repeated compression of the humeral head against the contents of the subacromial space
shoulder impingement syndrome
name 3 parts that shoulder impingement (compression) can cause trauma to.
- supraspinatus tendon (tendonitis; RC tear)
- subacromial/subdeltoid bursa (bursitis)
- long head of biceps tendon (biceps tendonitis)
name the classic sign of shoulder impingement syndrome.
pain on shoulder abduction
name 2 factors that allows excessive superior displacement of the humeral head that cause shoulder impingement syndrome.
- stiffness in GH inferior capsule
- instability of the GH joint from lax ligaments or weak RC muscles
name 3 factors that decrease volume in the subacromial space that cause shoulder impingement syndrome.
- inflammation
- scar tissue
- bone spurs on clavicle or acromion
how can we avoid shoulder impingement syndrome?
For GH abduction, past 90 degrees of shoulder elevation, externally rotate the humerus to avoid impact of greater tuberosity of humerus on the acromion.
partial dislocation of shoulder joint; shoulder ligaments cannot hold the weight of the arm in the absence of muscular (RC) activity.
shoulder subluxation
how are shoulder subluxations classified?
by finger space btwn the acromion and humeral head.*
what is used to support the subluxed shoulder?
sling
name 3 factors to consider when using a sling.
- instruct proper positioning for pt. when seated and in supine/sidelying in bed.
- typically used for pts. who are ambulating and for prolonged standing with ADL tasks.
- caution: use of slings all the the time even in elbow positions that do not allow shoulder or elbow motions
name 2 splints used for the neurological hand.
- resting hand splint
- wrist cock up splint
- flex wrist to extend the fingers (compromise wrist extension to get finger extension).
- splint in the anti-deformity position.
resting hand splint
- do not immobilize active finger movement if present.
- consider this if pt. has active finger motion.
wrist cock up splint
- a state in which the muscle is partially contracted and ready to act aka “resting muscle tone.”
- occurs from a complex sequence of activity among muscle spindles, gamma motor neurons, and alpha motor neurons, sensory and motor feedback loops.
muscle tone
name the 5 components of the muscle tone continuum.
- flaccidity
- hypotonicity
- normal
- hypertonicity
- rigidity
- no underlying muscle tone
- areflexive or loss of all reflexes
- hypermobile joint
flaccidity
- no resistance to PROM
- some slight muscle tone
- floppy
hypotonicity
increased resistance with increased velocity of movement during passive stretch
hypertonicity/spasticity
- cogwheel or lead pipe
- increased stiffness of movement as opposing muscle groups become active and “bind movement.”
rigidity
name 2 reasons why we may see abnormal muscle tone.
- a break down in muscle spindle activity and coordination of the alpha and gamma co-activating system
- an imbalance in agonist and antagonist muscle activity or a problem with inhibitory/excitatory actions btwn muscle groups.
describe the quick stretch test.
- stabilize extremity at joints.
- check PROM slowly through full or available ROM
- provide a quick stretch and feel the “catch”
- note where in the range
“catch” at the end of range
minimal
“catch” at the middle of the range
moderate
“catch” at the beginning of the range
severe
name 4 groups of muscles that can be tested with the quick stretch test.
- elbow flexors
- finger flexors
- wrist flexors
- elbow extensors
