What Are the Nerves of the Hand?

The innervation of the hand mainly comes from the median, ulnar and radial nerves. Because nerve damage not only causes sensory disturbances, but also often involves hand movement and sympathetic nerve function. Therefore, the function of the opponent is greatly affected. If it is not treated in time, once the small muscles of the hand atrophy, Affect the effect of treatment. Therefore, it is necessary to detect and treat the nerve damage of the hand in time.

Basic Information

English name

Hand nerve injury

Visiting department

Hand surgery

Common locations

Hand nerve

Common causes

Trauma; Ligaments or local masses compress nerves for a long time

Common symptoms

Sensory, motor and sympathetic dysfunction

Causes of hand nerve injury

There are many causes of hand nerve injury, which are mainly divided into traumatic nerve injury and compressive nerve injury. Traumatic nerve injury is mainly caused by trauma, and compressive nerve injury is often caused by ligaments or local masses that compress the nerve for a long time.

Clinical manifestations of hand nerve injury

The overall clinical manifestations of hand nerve injury are sensory, motor, and sympathetic nerve dysfunction, as well as a positive Tinel sign at the nerve injury site. Sympathetic dysfunction is mainly manifested as sweating dysfunction in the nerve distribution area. Because the innervation areas of different nerves are different, the specific performances are also different.

Median nerve injury

After median nerve injury, the main distribution areas of sensory and sympathetic nerve dysfunction are the thumb, thumb, middle finger, and ring finger. Obstacles and atrophy of the great fish muscles.

2. Ulnar nerve injury

After ulnar nerve injury, the main distribution areas of sensory and sympathetic nerve dysfunction are the palmar side of the ulnar side of the little finger and ring finger and the ulnar side of the back of the hand. The motor dominance area is mainly the small fish muscle and the intrinsic muscle of the hand. It is manifested as ring and little finger straightening disorders, sub-finger and parallel finger dysfunction, and fine motor dysfunction. Muscle atrophy is mainly manifested by atrophy of the small fish muscles and inner hand muscles.

3. Radial nerve injury

The radial nerve has only sensory and sympathetic nerves distributed below the wrist, and the distribution of dysfunction is mainly the radial half of the back of the hand.

Hand nerve injury examination

The more specific auxiliary examination after nerve injury is the EMG examination. However, the EMG examination of acute nerve injury is often not accurate. Therefore, the EMG test is generally used for cases of nerve injury with a duration of more than one month. For compressive nerve injury and closed traumatic nerve injury, B-ultrasound or magnetic resonance examination can also be performed to clarify the location, severity and cause of compression of nerve injury.

If you want to check the sympathetic nerve damage, you can perform a ninhydrin test to check whether there is sweat secretion in the nerve distribution area. Since this experiment is not a routine clinical examination, it is not necessary to prepare ninhydrin test strips.

Diagnosis of hand nerve injury

For a hand nerve injury with a clear history of trauma, it is not difficult to make a clear diagnosis based on clinical symptoms and signs. An EMG can be performed if necessary. If entrapment of the nerve is suspected, the cause and location of the entrapment should be clarified by auxiliary imaging examination.

Due to the complexity of neurological diseases, it is important not to think of hand nerve damage as soon as you see the sensations and motor dysfunction of the hand. Sexual diseases (such as diabetic peripheral neuropathy) must be considered and a comprehensive judgment made.

Hand Nerve Injury Treatment

Once traumatic hand nerve injury is confirmed, the continuity of the nerve is interrupted. In principle, the earlier the repair, the better the function recovery. If the nerve is broken and there is no defect, end-to-end suture can be used directly. If the nerve is defective due to serious pollution or old damage, nerve transplantation is generally required. At present, for small-scale digital nerve defects, nerve sheath bridging can be used to avoid nerve transplantation. After the nerve suture, plaster fixation is required for about 4 weeks.

If the continuity of the nerves exists, it can be treated conservatively for a period of time, depending on the recovery of the nerves, whether to continue the conservative treatment, or to perform neuroprobing and release surgery.

For compressive nerve injury, it is necessary to distinguish whether the compression is caused by the compression of pathological factors (such as local masses) or the compression of physiological factors (ligaments). If it is the former, timely surgery is required to remove the pathological Factors and release the nerves; if the latter, conservative treatment can be used for a period of time, if the conservative treatment is not effective, then surgery to release the nerves.

It should be noted that the treatment effect of nerve injury has certain uncertainty, because whether the nerve can fully restore function depends on the growth of the nerve and the target muscles of the hand, even if the doctor has performed nerve suture or nerve release well. Depending on the shrinking situation.

Prognosis of hand nerve injury

The prevention of traumatic hand nerve injury is mainly to strengthen labor protection, strengthen pre-job training, and enhance the work proficiency of workers. For compressive nerve injury, early treatment of primary diseases and reduction of strain are the best preventive measures.