APPLIED RADIOLOGICAL ANATOMY

Detailed explanation-1: -In the middle part of the deltoid, muscle fibers are oblique between the bands or between the bands and the half-cones. This multipennate structure favors strength instead of range of excursion of the muscle.

Detailed explanation-2: -Multipennate muscles have fascicles that insert on multiple tendons tapering towards a common tendon, like multiple feathers converging on a central point. A common example is the deltoid muscle of the shoulder, which covers the shoulder but has a single tendon that inserts on the deltoid tuberosity of the humerus.

Detailed explanation-3: -From this extensive origin the fibers converge toward their insertion on the deltoid tuberosity on the middle of the lateral aspect of the shaft of the humerus; the intermediate fibers passing vertically, the anterior obliquely backward and laterally, and the posterior obliquely forward and laterally.

Detailed explanation-4: -It is a multipennate muscle. It arises as four intramuscular septa, which interdigitate with the three tendons at the insertion site (one each for the anterior, posterior and middle parts).