Upperlimb

The upper limb refers to the region of the body from the shoulder girdle to the fingertips. It is composed of the pectoral girdle (clavicle and scapula), the arm (brachium), forearm (antebrachium), and the hand (manus). Its primary functions include manipulation of objects, tool use, and load bearing, with a wide range of motion.

Bones and joints form the framework of the upper limb. The clavicle and scapula form the shoulder girdle, while the arm contains the humerus. The forearm contains the radius and ulna, and the hand includes the carpal bones in the wrist, the metacarpals in the palm, and the phalanges in the fingers. Joints include the shoulder (glenohumeral), elbow (humero-ulnar and humero-radial), proximal and distal radioulnar joints, and the wrist (radiocarpal) with intercarpal articulations. The upper limb is supplied by the brachial plexus, giving rise to nerves such as the musculocutaneous, axillary, radial, median, and ulnar nerves, and by arteries including the subclavian, axillary, and brachial, which give rise to the radial and ulnar arteries.

Muscles organize into functional groups. The shoulder region features the rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) and the deltoid. The arm contains the biceps brachii, triceps brachii, and brachialis; the forearm houses the flexor and extensor groups, while the hand contains intrinsic muscles that refine grip and finger movements. Movements of the upper limb include flexion and extension, abduction and adduction, rotation, pronation and supination, and varied grip patterns.

Clinical relevance includes common injuries such as shoulder dislocation, rotator cuff tears, clavicle or humerus fractures, distal radius fractures, carpal tunnel syndrome, and various compressive neuropathies. Developmentally, the upper limb arises from embryonic limb buds and undergoes coordinated growth, innervation, and vascularization.