Question

1. Discuss two specific muscles of the Axial Skeleton. Detail their attachment, insertion, joint, and adjacent ligaments if any. Please include references

Answer 1

The muscle attached to the axial skeleton is called axial muscles , they form the head, neck, core muscles of the body

Pectoralis major

It is the axial muscle present infront of the chest.

ORGIN: Clavicular head: anterior surface of the medial half of the clavicle.
         Sternocostal head: anterior surface of the sternum, the superior six costal cartilages, and the aponeurosis of the external oblique muscle

INSERTION: Lateral lip of the bicipital groove of the humerus

FUNCTION:Clavicular head: flexes the humerus

Sternocostal head: horizontal and vertical adduction, extension, and internal rotation of the humerus
Depression and abduction of the scapula

JOINT ASSOCIATED WITH PECTORALIS MAJOR : SHOULDER JOINT

LIGAMENT ADJASCENT TO THE SHOULDER

Glenohumeral Ligaments (GHL)

Coraco-acromial Ligament (CAL)

Coraco-clavicular Ligaments (CCL)

Transverse Humeral Ligament (THL)

2)Latissimus dorsi muscle

ORGIN:Spinal processes of vertebrae T7-L5, thoracolumbar fascia, iliac crest, lower3 or 4 ribs and inferior angle of scapula bone.

INSERTION :Floor of intertubercular groove of the humerus Bone

FUNCTION:Adducts, extends and internally rotates the arm

                powerful rotator of the thrunk

Joint associated with the muscle is SHOULDER JOINT