Shoulder Complex Biomechanics - GHJ
what occurs during GHJ internal rotation?
anterior roll, posterior glide greater tubercle moves towards sternum
what motion does the inferior anterior band GH ligament limit?
anterior translation
what tissues are on tension during GHJ external rotation?
internal rotators- teres major, anterior delt, pec major anterior capsule
what tissues are on tension during GHJ flexion?
latissimus dorsi, triceps, posterior deltoid posterior and inferior capsule
what tissues are on tension during GHJ ADduction?
supraspinatus and middle deltoid superior GHJ ligament
when arm is at the side where is the synovial capsule of the GHJ taut and where is it in slack?
taut superiorly slack anteriorly and inferiorly
what tissues are on tension during GHJ ABduction?
teres major, pec major, coracobrachialis inferior capsule inferior ligaments (anterior, axillary and posterior bands)
what happens to the synovial capsule of the GHJ when the arm is ABducted and externally rotated?
tightens creating closed pack position for GHJ
in what plane and along what axis do internal and external rotation of the GHJ occur?
transverse plane, vertical axis
what is the angle of inclination for the humeral head/neck?
130-150 degrees
what is the angle of torsion for the humeral head/neck?
30 degrees
in what position is the inferior axillary pouch GH ligament most tensioned?
90 degree ABD
in what position is the inferior posterior band GH ligament most tensioned?
90 degree ABD + IR
what is inside the subacromial space?
Coracohumeral ligament (undersurface) Superior joint capsule Subacromial bursa Supraspinatus tendon Biceps LH
what motion does the inferior axillary pouch GH ligament limit?
inferior & anterior translation
what motion does the superior GH ligament limit?
inferior and anterior translation
what happens during GHJ ADduction?
inferior roll, superior glide
what motion does the coracohumeral ligament limit?
inferior translation
what happens during GHJ ABduction?
superior roll, inferior glide
GHJ TISSUES ON TENSION
REFER TO NOTES
Arthro-osteo kinematics of the shoulder complex (full, pain free functional overhead motion) what is occurring at each joint during overhead flexion?
SCJ :elevation, retraction, posterior rotation ACJ : upward rotation, posterior tilt, ER STJ: upward rotation GHJ: flexion
Arthro-osteo kinematics of the shoulder complex (full, pain free functional overhead motion) what is occurring at each joint during ADduction?
SCJ: depression, protraction, anterior rotation ACJ: downward rotation, anterior tilt, IR STJ: downward rotation GHJ: ADduction
Arthro-osteo kinematics of the shoulder complex (full, pain free functional overhead motion) what is occurring at each joint during extension?
SCJ: depression, protraction, anterior rotation ACJ: downward rotation, anterior tilt, IR STJ: downward rotation GHJ: extension
Arthro-osteo kinematics of the shoulder complex (full, pain free functional overhead motion) what is occurring at each joint during overhead ABduction?
SCJ: elevation, retraction, posterior rotation ACJ: upward rotation, posterior tilt, ER STJ: upward rotation GHJ: ABduction
what are characteristics of the glenohumeral joint?
ball and socket synovial joint with 3 DOF
what structures create a vault above the subacromial space?
coracoid process acromion coracoacromial ligament
what motion does the middle GH ligament limit?
excessive ER anterior translation
what tissues are on tension during GHJ internal rotation?
external rotators- posterior delt, infraspinatus, teres minor
what osteokinematic motions occur at the glenohumeral joint?
flex/ext abd/add IR/ER
in what plane and along what axis do ABduction and ADduction of the GHJ occur?
frontal plane, anterior to posterior axis
in what position is the middle GH ligament most tensioned?
most tension: 45-60 degree ABD + ER
in what position is the inferior anterior band GH ligament most tensioned?
most tension: 90 degree ABD + ER
in what position is the coracohumeral ligament most tensioned?
most tension: full ADD
in what position is the superior GH ligament most tensioned?
most tension: full ADD
what tissues are on tension during GHJ extension?
pec major, anterior delt, biceps LH anterior capsule
what happens during GHJ external rotation?
posterior roll, anterior glide greater tubercle moves away from sternum
what motion does the inferior posterior band GH ligament limit?
posterior translation
what happens during GHJ extension?
pure spin
what happens during GHJ flexion?
pure spin
in what plane and along what axis do flexion and extension of the GHJ occur?
sagittal plane, medial to lateral axis
