Major Surface Muscles

1. The major surface muscles include the following: Trapezius, Deltoids, latissimus dorsi, Pectoralis major, Biceps, Triceps, Rectus femoris, bicep femoris, semitendinosus, Gluteus muscles, abdominals, Lateral Gastrocnemius, serratus dorsi, external oblique, and soleus.

Trapezius- Origin:

Upper: Base of skull, Occipital protuberance and posterior ligaments of neck.

Middle: spinous process of 7C and T1-T3

Lower: Spinous process of T4-T12

Insertion:

Upper: Posterior aspect of the lateral clavicle.

Middle: Medial border if the acromion process and the upper boarder of the acromion

Lower: Base of the scapular spine.

Action:

Upper: Scapula elevation and extension of the head at neck

Middle: Elevation, upward rotation and adduction of scapula

Lower: …show more content…
Biceps brachii- origin:

Long head: Supraglenoid tubercle above the superior lip of glenoid fossa

Short head: Coracoid process of scapula and upper lip of glenoid fossa

Insertion:

Tuberosity of radius and bicipital aponeurosis

Action:

Flexion of elbow, supination of forearm, weak flexion of shoulder joint

Exercise:

Bicep curl, hammer curl, barbell curl.

Triceps brachii- origin:

Long head: Infraglenoid tubercle below inferior lip of glenoid fossa scapula

Lateral head: Upper half of posterior or surface of humerus

Medial head: Distal 2/3 of posterior surface of humerus

Insertion:

Olecranon process of ulna

Action:

Long, lateral, medial head: Are involved in the extension of the elbow.