Shoulder Mechanisms and Counterstrain Flashcards
if you treat SD in T spine, upper ribs, lower C spine?
upper extremity dysfunction will frequently take care of itself
does shoulder motion involved just one joint or articulation?
no
shoulder motion?
dynamic interplay between scapulothoracic articulation and the glenohumeral, acromioclavicular and sternoclavicular joints
motions of shoulder
flex/extend
abduct/adduct
internal/external rotation
glenohumeral joint
designed for maximum motion at expense of decreased stability
very little osseous support
shallow glenoid cavity
scapulothoracic articulation?
scapula glides over ribcage with shoulder motion
scapulothoracic rhythm?
first 30 degrees of shoulder abduction occurs at glenohumeral joint (supraspinatus)
thereafter, for every 2 degrees of motion the glenohumeral joint, there is 1 degree of motion at scapulothracic articulation
scapulothoracic articulation restricted?
thoracic spine and rib dysfunction
glenohumeral joint compensates
-overuse to instability impingement rotator cuff tendonitis and tear
sternoclavicular joint
capable of anteroposterior, superoinferior rotational motions
injury, infections, and other can cause problems
posterior dislocation of sternoclavicular joint?
can compromise important neurovascular structures
ex/ seatbelt injury
acromioclavicular joint
allows anteroposterior, superoinferior, and rotational motion
frequently becomes separated
upper extremity innervation?
C5-T1 brachial plexus
between anterior and middle scalene
between first rib and clavicle
underneath pectoralis minor
SD in cervical spine, upper thoracic spine, upper ribs, scalene muscles, clavicle, pectoralis?
can have negative impact on brachial plexus and upper extremity dysfunction
primary flexors of glenohumeral?
pectoralis major
deltoid (anterior)
coracobrachialis
nerve of pectoralis major?
C5-T1
nerve of deltoid (anterior)
axillary nerve C5 C6
corachobrachialis innervation?
musculocutaneous nerve
C5, C6, C7
primary extensors of glenohumeral?
lat dorsi
teres major
deltoid (posterior)
long head triceps brachii
nerve of lat dorsi?
thoracodorsal (C6 7 8)
nerve of teres major
lower subscapular
C5 C6
deltoid muscle (posterior) nerve?
C5 C6 axillary
long head triceps muscle
radial nerve
C 6 7 8
primary abductors of glenohumeral
deltoid
supraspinatus
nerve of supraspinatus
suprascapular nerve
C4 5 6
primary adductors of glenohumeral?
pec major
lat dorsi
teres major
long head triceps brachii
primary external rotators of glenohumeral?
infraspinatus
teres minor
deltoid
teres minor innervation?
C5 6 axillary nerve
infraspinatus innervation?
suprascapular nerve C5 C6
primary internal rotators glenohumeral?
subscapularis pec major lat dorsi deltoid teres major
subscapular nerve?
C5 6 7
upper and lower subscapular nerves
SD and nerves?
can affect nerve roots
resulting in weakness of innervated muscles
four muscles of rotator cuff?
supraspinatus
infraspinatus
teres minor
subscapularis
keep head of humerus centered in glenoid fossa
-move and stabilize glenohumeral joint
arterial supply of glenohumeral joint?
left and right subclavian arteries
pass over top of first rib between anterior and middle scalene muscles
upper extremity arterial supply?
may be affected by SD of anterior and middle scalenes, upper thoracic and cervical vertebrae, upper ribs, clavicles, and fascia of neck and upper extremity
venous drainage of upper extremity?
subclavian and brachiocephalic veins
anterior to scalene muscles
SD in venous drainage - can lead to congestion of upper extremity
lymphatic drainage of upper extremity?
drain through thoracic inlet
SD can produce mechanical restriction to lymph flow and congestion can occur
-slower healing
sympathetics of upper extremity?
T2-T6
-cell bodies of preganglionic neurons concerned with upper extremity located in upper thoracic spinal segements
smooth muscles in walls of lymphatics contract when sympathetic stimulation
reduces size of lumen, thereby impairing lymphatic drainage
upper thoracic SD?
increases sympathetic tone to upper extremity
decreased lymphatic dgainage
may lead to swelling, impaired function and recovery
tensegrity and kinetic chain
entire body is interconnected by a vast network of connective tissue
one area is tight, whole system gets tight
mechanics of throwing?
force transmitted from ground to upper extremity
during overhead movements, what percentage of kinetic energy of upper extremity is generated by legs and trunk?
48%
what stimulates scapular retraction?
ipsilateral hip and trunk extension
what muscles decelerate glenohumeral joint when throwing
posterior shoulder muscles
posterior deltoid and teres minor
lat dorsi tightness?
reduced shoulder flexion
thoracolumbar junction
frequently find SD at T10-L2
psoas major, diaphragm, lat dorsi, thoracolumbar fascia
may also see somatovisceral reflex?
-adrenal glands
posture imbalance?
sitting - kyphosis
protracts scapula
pec minor and biceps tighten
hamstring and psoas major also frequently tighten with prolonged sitting
counterstrain
shoulder injuries frequently associated with tender points
supraspinatus, subscapularis, biceps are common
supraspinatus tender point
in supraspinous fossa
subscapularis tender point
in posterior axillary fold
biceps tender point
along long head through bicipital groove
principles of counterstrain?
locate tender point establish pain scale find position reducing 70-100% of pain hold position 90 seconds slowly return to position reassess
shoulder problem slow or non-responsive to treatment?
think of systemic problems like diabetes or hypothyroidism
nerve growth?
inch per month
