Platysmus muscle: located in the superficial fascia of the neck, originating from the fascia on the surface of the pectoralis major and deltoid muscles, and inserting at the corner of the mouth, the lower edge of the mandible and the skin of the lower face

The sternocleidomastoid muscle: Mostly covered by the platysus muscle, it originates from the front of the sternum manubrium and the sternal end of the clavicle, and its two heads meet obliquely posterior and upward to terminate at the mastoid process of the temporal bone. Function: Contraction of the muscles on one side causes the head to tilt to the same side and face to the opposite side. Contraction of both sides at the same time causes the head to tilt back.

shallow group

Deep group: The erector spinae muscle is located in the grooves on both sides of the spine. It is the longest and largest of the back muscles. Contraction of one side of this muscle causes the spine to flex to the same side. Contraction of both sides at the same time makes the spine extend backward and tilt the head back.

Pectoralis major: Located in the upper front part of the thorax, it originates from the medial 2/3 of the clavicle, the sternum and the 1st to 6th costal cartilage, and ends at the greater tubercle ridge of the humerus. When contracting, the shoulder joint can be adducted and internally rotated. It can lift the ribs upward and expand the thorax to aid inhalation

Pectoralis minor: For the deep surface of the pectoralis major, it is triangular in shape. Its function is to pull the scapula forward and downward. When the scapula is fixed, the ribs can be raised to assist in inhalation

Serratus anterior: It is a broad flat muscle located on the side wall of the thorax; it is innervated by the long thoracic nerve; if this muscle is paralyzed, the inner edge and lower corner of the scapula will leave the thorax and protrude subcutaneously, which is called a "winged shoulder"

Aortic hiatus: approximately level with the 12th thoracic vertebra, through which the aorta and thoracic duct pass

Esophageal hiatus: approximately level with the 10th thoracic vertebra, on the left front and upper side of the aortic hiatus, through which the esophagus and vagus nerve pass

Vena cava foramen: level with the 8th thoracic vertebra, in the central tendon on the right front and upper side of the esophageal hiatus, where the inferior vena cava passes

External oblique muscle: It is located in the superficial layer of the anterolateral part of the abdomen. The lower edge of the peritoneum is thickened and curled. It is connected between the anterior superior iliac spine and the pubic tubercle. It is called the inguinal ligament. There is a small bundle of tendon fibers at the medial end of the inguinal ligament that folds downward and posteriorly to the pubic comb, which is called the lacunar ligament. The part of the lacunar ligament that extends and attaches to the pubic comb is called the pubic pectin ligament Above and outside the pubic tubercle, the aponeurosis forms a triangular hole, called the superficial (subcutaneous) inguinal canal ring.

Internal oblique: located deep to the external oblique

Abdominal transverse machine: located on the deep internal oblique surface of the abdomen

Rectus abdominis: located on both sides of the midline of the anterior abdominal wall

Deltoid muscle: Located on the shoulder, triangular in shape, innervated by fluid nerves. Function: Abduct the shoulder joint, the anterior muscle bundle can flex and internally rotate the shoulder joint, and the posterior muscle bundle can extend and externally rotate the shoulder joint. When this muscle is paralyzed and atrophied, the acromion protrudes under the skin, making the shoulder square.

Subscapularis: Located in front of the scapula, it is triangular in shape. Adducts and internally rotates the shoulder joint during contraction

Biceps brachii: innervated by musculocutaneous nerve. When this muscle contracts, it flexes the elbow joint, can supinate the forearm when it is in the pronated position, and assists in flexing the shoulder joint.

Coracobrachialis: flexes and adducts the shoulder joint forward

Brachialis: flexes the elbow joint

Triceps brachii (arm muscle group): Its function is to extend the elbow joint. The long head can also extend and adduct the shoulder joint; innervated by the radial nerve

Gluteus medius and gluteus minimus: abduct the hip joint,

piriformis muscle

Sartorius muscle: Located superficially on the front and medial side of the thigh, it is the longest muscle in the body in the shape of a flat belt (function: flexes the hip and knee joints, and internally rotates the flexed knee joint)

Quadriceps: Located in the front of the thigh, it is the largest muscle in the body (function: flexing the hip joint and extending the knee joint)