The
rotator cuff consists of four muscles: infraspinatus, supraspinatus,
teres minor and subscapularis; the tendons of which blend
with the capsule of the glenohumeral joint, aiding its stability.
Due to its location in the subacromial arch, the supraspinatus
is particularly susceptible to injury.
The supraspinatus
muscle, together with the deltoid, raises the arm to initiate
abduction.
The weakest point of the supraspinatus tendon is the part,
which forms the cuff over the joint in the area that is 1cm
from the attachment of the tendon to the humerus. It is at
this point that ruptures most often occur. |