Origin and Insertion
The origin of a muscle is the proximal point where the muscle
attaches to a bone and is also the least movable part of the muscle. The
insertion of a muscle is the distal point where the muscle attaches to a bone
and is also the most movable part of the muscle. The origin of the pectoralis
major includes the clavicle, sternum, the costal cartilage of the upper ribs,
and the aponeurosis of the external obliques. The insertion of the pectoralis
major includes the superior and anterior portion of the humerus.
attaches to a bone and is also the least movable part of the muscle. The
insertion of a muscle is the distal point where the muscle attaches to a bone
and is also the most movable part of the muscle. The origin of the pectoralis
major includes the clavicle, sternum, the costal cartilage of the upper ribs,
and the aponeurosis of the external obliques. The insertion of the pectoralis
major includes the superior and anterior portion of the humerus.