Claw Hand

　　The ulnar nerve originates from the medial bundle of the brachial plexus, descends medially along the brachial artery, turns medially in the middle segment of the upper arm, passes through the ulnar groove behind the medial epicondyle of the humerus, and passes between the ulnar head of the flexor carpi ulnaris and the humeral head, giving off branches to the flexor carpi ulnaris, and then entering the palmar side of the forearm between the flexor carpi ulnaris and the flexor digitorum profundus, giving off branches to the ulnar half of the flexor digitorum profundus, and then accompanying the ulnar artery, reaching the wrist on the radial deep surface of the flexor carpi ulnaris, about 5 cm above the wrist, giving off a dorsal branch to the ulnar side of the hand. The main trunk divides into deep and superficial branches through the carpal tunnel between the pisiform and hamate bones, the deep branch passes through the hypothenar muscle into the deep palm, innervating the hypothenar muscle, all interosseous muscles, and the medial heads of the 3rd and 4th lumbricals and the adductor pollicis and the medial head of the flexor pollicis brevis. The superficial branch extends to the ulnar side of the palm and the skin of one and a half fingers on the ulnar side. The ulnar nerve is prone to injury at the wrist and elbow.

　　Wrist injuries are mainly manifested as ring and little finger claw hand deformities caused by paralysis of the interosseous muscles, lumbricals, and adductor pollicis, as well as finger adduction and abduction disorders and Froment's sign, and sensory disorders in the ulnar half of the hand and one and a half fingers on the ulnar side, especially the loss of sensation in the little finger. Above the elbow injury, in addition to the above symptoms, there is also a functional disorder of flexion of the distal phalanges of the ring and little fingers.

　　Wrist injuries are mainly manifested as ring and little finger claw hand deformities caused by paralysis of the interosseous muscles, lumbricals, and adductor pollicis, as well as finger adduction and abduction disorders and Froment's sign, and sensory disorders in the ulnar half of the hand and one and a half fingers on the ulnar side, especially the loss of sensation in the little finger. Above the elbow injury, in addition to the above symptoms, there is also a functional disorder of flexion of the distal phalanges of the ring and little fingers.

　　Wrist injuries are mainly manifested as ring and little finger claw hand deformities caused by paralysis of the interosseous muscles, lumbricals, and adductor pollicis, as well as finger adduction and abduction disorders and Froment's sign, and sensory disorders in the ulnar half of the hand and one and a half fingers on the ulnar side, especially the loss of sensation in the little finger. Above the elbow injury, in addition to the above symptoms, there is also a functional disorder of flexion of the distal phalanges of the ring and little fingers.

　　Diagnosis is mainly based on the history of trauma and clinical manifestations. Wrist injuries are mainly manifested as ring and little finger claw hand deformities caused by paralysis of the interosseous muscles, lumbricals, and adductor pollicis, as well as finger adduction and abduction disorders and Froment's sign, and sensory disorders in the ulnar half of the hand and one and a half fingers on the ulnar side, especially the loss of sensation in the little finger. Above the elbow injury, in addition to the above symptoms, there is also a functional disorder of flexion of the distal phalanges of the ring and little fingers.

　　Wrist injuries are mainly manifested as ring and little finger claw hand deformities caused by paralysis of the interosseous muscles, lumbricals, and adductor pollicis, as well as finger adduction and abduction disorders and Froment's sign, and sensory disorders in the ulnar half of the hand and one and a half fingers on the ulnar side, especially the loss of sensation in the little finger. Above the elbow injury, in addition to the above symptoms, there is also a functional disorder of flexion of the distal phalanges of the ring and little fingers.

　　The recovery of hand intrinsic muscle function after ulnar nerve injury repair is poor, especially in high-level injuries. In addition to repairing the nerve as soon as possible, the motor and sensory nerves of the ulnar nerve at the wrist have been divided into bundles, which can be sutured with nerve bundles to improve the surgical effect. Late functional reconstruction is mainly to correct the claw hand deformity.