- See:
-
Abductors of the Shoulder:
-
Rotator cuff;
- Anatomy:
-
origin: medial 2/3 of supraspinatus fossa above spine of scapula;
-
insertion: superior surface of greater tuberosity of humerus and capsule of shoulder joint;
-
action: abduction of humerus at GHJ: stabilization of glenohumeral joint;
-
nerve supply: suprascapular, C4,
C5
-
synergist:
deltoid;
- Function:
- supraspinatus muscle contributes to GH stability, demonstrating peak
activity in late cocking phase of throwing mechanics.
- while the supraspinatus undoubtably plays an important role in shoulder
function, it is sometimes difficult to demonstrate its necessity;
- for instance complete experimental paralysis of supraspinatus will simply
reduced the force of abduction, w/ no other loss of function;
- Injury:
- overuse of supraspinatus & resulting fatigue can subject amateur
athlete to shoulder injuries.
- about 5% of shoulders that have had an anterior dislocation will sustain
an irrepairable injury to the subscapularis, which will contribute to
further instability;
- in this case, a
pectoralis transfer would be indicated;
- Exam:
- the supraspinatus muscle is tested with the shoulder abducted 90
degrees, flexed 30 deg and then maximally internally rotated;
- downward pressure is resisted primarily by the supraspinatus;
Clarification of the role of the supraspinatus muscle in shoulder function.
The microvascular pattern of the supraspinatus tendon.
Arthroscopic treatment of massive rotator cuff tears. Clinical results and biomechanical rationale.
Advancement of the supraspinatus muscle in the repair of ruptures of the rotator cuff.
A quantitative histological study of the vascularity of the rotator cuff tendon.
Year Book: Isolated Rupture of the Tendon of the Subscapularis Muscle: Clinical Features in 16 Cases.
The role of the supraspinatus and infraspinatus muscles in glenohumeral kinematics of anterior should instability.
Changes in the moment arms of the rotator cuff and deltoid muscles with abduction and rotation.
Suprascapular neuropathy in volleyball players.
