How many parts does the arm have? What are their names?

The human body can be divided into head, trunk, two arms, two legs and four parts. The trunk consists of neck, chest, abdomen and back. The upper limbs are composed of shoulders, upper arms, elbows, lower arms, wrists and hands. The lower limbs are composed of straddle, thigh, knee, calf, ankle and foot. Today, we will focus on what are the main parts of our arms and what are their names. The names of joints above the arm mainly include: clavicle, acromioclavicular ligament, acromion, conus ligament, trapezius ligament, coracoacromial ligament, coracoid ligament, coracoid process, shoulder joint capsule, tendon of long head of biceps brachii and scapula.

The elbow joint in the middle arm is mainly composed of humerus, humeral trochlea, lateral epicondyle, medial epicondyle, radial capitulum, olecranon of ulna, semilunar incisor, coronoid process, radial trochanter, radius, ulna, radial styloid process and ulnar styloid process.

The position under the arm is our hand. There are many bones and joints in the arm, which are composed of collateral ligament, metacarpophalangeal joint, carpometacarpal joint, hamate, carpometacarpal joint, skull, small polygonal bone, carpal ligament, triangle bone, navicular bone, articular bone, lunate bone, radiocarpal joint, distal radioulnar joint, ulna and radius.

There are also many muscles on the arm. Upper limbs are composed of shoulder muscles, arm muscles, forearm muscles and hand muscles. The muscles of the shoulder are mainly distributed around the shoulder joint, which can protect it from injury during exercise. The most important thing is deltoid muscle. Arm muscles are mainly divided into anterior and posterior muscles. The anterior muscle consists of flexor, biceps brachii, brachialis and coracoid-brachialis. The back consists of extensor and triceps brachii. The muscles in front are mainly distributed around the ulna and radius, and are called long prismatic muscles, which can also be divided into two groups. The front is called flexor group, and the back is called extensor group. All the muscles of the hand are located in the palm of the hand and are divided into lateral muscles, medial muscles and intermediate muscles.