Ulnar nerve palsy
Introduction
Introduction to ulnar nerve palsy The ulnar nerve is close to the superficial part of the humerus and the ulnar olecranon (the ulnar nerve groove), which is easily affected by fracture or dislocation. The typical manifestation of ulnarnerveparalysis is the claw-shaped hand deformity, with the ring finger and the little finger as the thumb, the thumb is often in the abduction state, the fingers are separated, the combined movement is restricted, and the little finger movement is lost. The sensory loss zone is mainly on the ulnar side of the hand, and the stalk side of the small fish, the little finger and the ring finger. basic knowledge The proportion of sickness: 0.01% Susceptible people: no specific people Mode of infection: non-infectious Complications: elbow valgus deformity
Cause
Rule of ulnar nerve palsy
Cause:
The ulnar nerve is the most superficial in the posterior aspect of the humerus and the olecranon. The stab wound or fracture is easily affected. The elbow support compression, trauma, leprosy, humeral dysplasia and elbow valgus deformity can also be caused. Elbow syndrome is also common.
Elbow valgus deformity (35%):
Elbow joints with an angle of more than 20° are called elbow valgus. Elbow valgus deformity after elbow trauma is less common than elbow varus. Most patients come to seek treatment for secondary elbow ulnar neuritis. The cause of the disease is mostly caused by poor treatment of the elbow bone and joint.
Elbow syndrome (30%):
The ulnar nerve is compressed due to traumatic arthritis of the elbow. There is a thickened fibrous band between the two ends of the ulnar wrist flexor, which is called the ulnar syndrome. There is an arc-shaped narrow and deep bone groove between the upper iliac crest and the ulna eagle, and a deep fascia is placed on the upper to form a bony fiber sheath, that is, a ulnar nerve groove, also called an elbow rule tube. Inside the tube are the ulnar nerve and the ulnar side of the anterior movement and vein.
Prevention
Ulnar nerve palsy prevention
1. Pay attention to rest and avoid pressure on the hands and elbows.
2, due to the feeling of the hand of the disease, the function is reduced, in the daily activities to protect the affected part, to prevent secondary damage, such as burns, abrasions and so on.
Complication
Ulnar nerve palsy complications Complications elbow valgus deformity
The fingers are separated, the combined action is restricted, and the little finger movement is lost.
Symptom
Ulnar nerve palsy symptoms common symptoms paralysis hand function completely loss of sensory hand muscle atrophy
1. The typical manifestation of ulnar nerve injury is the loss of small muscle motor function in the hand, which affects the fine movement of the finger.
(1) ulnar wrist flexor numbness and due to the antagonistic effect of the radial flexor digitorum, the hand is skewed to the temporal side;
(2) Abdominal muscle palsy and abduction of the thumb due to antagonism of the ink muscle;
(3) due to excessive contraction of the extensor muscle, the joint of the base of the finger is overextended, the end of the joint is flexed, the small fish is flat, the interosseous muscle is atrophied, the fingers are separated, the closure is limited, the little finger movement is lost and the outreach position is lost, and the fine finger movement is lost. , 4-5 means that the flexion position cannot be straightened, such as a claw-shaped hand;
(4) When the ulnar nerve is damaged in the middle and lower third of the forearm, only small muscle paralysis of the hand is seen.
2, the sensory disorder in the back of the hand side of the ruler, small fish, small finger and ring finger side half. The ulnar nerve, median nerve, musculocutaneous nerve, and the iliac artery initial segment are closely arranged to form a vascular bundle, often combined with injury.
Examine
Ulnar nerve palsy examination
Electromyography checks for nerve damage and degree, and neurological examination.
Electromyography is a biocurrent that describes the activity of neuromuscular units to determine the functional state of the neuromuscular muscles, in combination with clinical diagnosis of the disease, and the use of electromyography can help distinguish the myogenic or neurogenicity of the lesion. . For the diagnosis of nerve root compression, EMG has a unique value.
Diagnosis
Diagnosis and differentiation of ulnar nerve paralysis
Diagnose based on
1. The movement of the little finger is lost, the flexion of the wrist and the finger is weak, the thumb cannot be received and the palm is facing, and the wrist is biased toward the temporal side when the wrist is bent.
2, small fish muscles and various interosseous muscles often atrophy.
3, the little finger and the ring finger feel side obstacles.
4, often have humeral fractures, elbow dislocation, wrist or elbow trauma directly damage the history of ulnar nerve, can also be seen in patients with Kashin-Beck disease and leprosy.
5. EMG and nerve conduction velocity are abnormal.
Differential diagnosis
1, play of median nerve (play of median nerve): muscle atrophy distributed in the forearm eye 1/3 and large fish muscles, and flexion. The patient used the thumb and the base of the finger during the pinch test.
2, the median nerve and ulnar nerve combined damage: the upper limb trauma fracture compression, etc., the two nerve paralysis in the forearm volar side of the localized muscle atrophy, and the diaphragm, humeral flexor longus, iliac crest short wrist There is no atrophy in the muscles, and the size of the inter-muscular muscles and interosseous muscles is atrophy, and the palms are flat and "hands-on".
3, musculocutaneous nerve injuiy: muscle atrophy in front of the forearm.
