Anatomy Dissection 9 Flashcards
What role does the posterior (spinal) part of deltoid have?
Extension at shoulder
What role does the middle (acromial) part of deltoid have?
Abduction at shoulder (taking over from supraspinatus beyond 15 degrees)
What role does the anterior (calvicular) part of deltoid have?
Mainly flexion at shoulder
What does the ascending, middle and descending parts of trapezius do?
Ascending - scapular depression
Middle - retraction
Descending - Elevation
What parts of trapezius contract together to produce superior rotation of glenoid fossa?
Ascending and descending
What muscle involved in the shoulder does elevation of scapula and inferior rotation of glenoid fossa?
Levator scapulae
What two muscles are involved in retraction of scapula and inferior rotation of glenoid fossa?
Rhomboid major and minor
Name the four rotator cuff (SITS) muscles?
- Supraspinatus
- Infraspinatus
- Teres minor
- Subscapularis
What SITS muscle does the first 15 degrees abduction at shoulder?
Spuraspinatus
What SITS muscles stabilises head of humerus in glenoid/lateral rotation at shoulder?
Infraspinatus and teres minor
What SITS muscle stabilises head of humerus in glenoid/medial rotation at shoulder
Subscapularis
Name the clinically important group of muscles which attach between the scapula proximally and the tubercles of head of humerus distally?
Rotator cuff muscles
What rotator cuff muscles medially rotates the humerus at shoulder joint?
Subscapularis
What rotator cuff muscle laterally rotates humerus at shoulder joint?
Infraspinatus and teres minor
What rotator cuff muscle initiates abduction first 15 degrees of humerus before the middle fibrers of deltoid take oveR?
Supraspinatus
