Please enable JavaScript.
Coggle requires JavaScript to display documents.
Integrated functions of the Shoulder complex - Coggle Diagram
Integrated functions of the Shoulder
complex
Combined scapulohumeral motions of the complex will
Distributes the motion of the joints, permitting a large ROM with less
compromise of stability than would occur if the same range occurred at one
joint
Maintains the glenoid fossa in an optimal position in relation to the head of
the humerus, increasing joint congruency while decreasing shear forces
Permits muscles acting on the humerus to maintain a good length-tension
relationship while minimizing or preventing active insufficiency of the gelnohumeral muscles
ST and GH contributions
Scapulohumeral Rhythm
all four joints must properly
interact for normal shoulder motion to occur.
An excellent example of this interaction is the scapulohumeral rhythm
Movement of scapula on thorax with the combined movement of humerus
Concomitant movement of both segments
Overall ration of motion is 2:1 happening at GHJ and STJ respectively
Example
When the total range of elevation(flexion/abduction) occurs at 180
degrees
1 more item...
SC and AC contributions
Scapulothoracic motion is an integral part of nearly
every shoulder movement.
Furthermore, motion at the scapulothoracic joint is
dependent on the combined movements of the AC and SC joints.
The full 60 degrees of scapulothoracic upward
rotation is achieved by combining about 30 degrees of clavicular elevation with 30 degrees of AC joint
upward rotation
Upward rotators of Scapula
Motion of the scapula are primarily produced by the
balance of forces between the Trapezius Serratus anterior muscles
Axis of scapular upward rotation progresses through out the motion – muscles activated are also different
Upper trapezius
Lower trapezius
Serratus Anetrior
contributes to the combined clavicular and scapular motion
contribute to upward rotation when
the axis is at the ACJ
contributes to initial elevation of clavicle and SCJ retraction