Carpal tunnel syndrome

Introduction Carpal tunnel syndrome is a corresponding clinical symptom caused by compression and stimulation of the median nerve in the carpal tunnel. Any factor that increases or increases the content of the carpal tunnel or reduces the volume of the carpal tunnel can cause the disease. The carpal tunnel is a bone fiber tube in the palm of the hand. The flexor hallucis longus and the four flexor digitorum tendons, the four flexor digitorum tendons and the median nerve enter the hand through this tube. The carpal tunnel is on the side of the palm of the wrist and consists of the carpal bone and the transverse ligament of the wrist. The transverse ligament of the wrist is tough and the proximal margin is thickened, which is the main factor for compressing the median nerve. The median nerve is superficially located in the carpal tunnel and is easily compressed by the transverse ligament of the wrist, causing damage.

Cause

Causes of carpal tunnel syndrome:

The onset of carpal tunnel syndrome is associated with chronic injury. Hand and wrist are prone to disease when the labor intensity is high.

(1) Chronic injury can cause tendon, synovium and nerve edema in the carpal tunnel, and there will be aseptic inflammation and secondary fibroplasia. Hypertrophy of the transverse ligament of the wrist, tissue edema in the carpal tunnel, and fibrosis can cause compression of the median nerve.

(2) Wrist fracture, dislocation, and malunion reduce the volume of the carpal tunnel and compress the median nerve. This is also a common cause of carpal tunnel syndrome.

(3) carpal tunnel masses, such as ganglion cysts, hemangioma, lipoma, etc., can compress the median nerve, causing carpal tunnel syndrome.

Therefore, carpal tunnel syndrome is caused by a variety of reasons. Although the performance of the median nerve in the carpal tunnel is compressed, the cause is different.

an examination

Related inspection

One-handed trial of the wrist test

Diagnosis of carpal tunnels:

Carpal tunnel syndrome occurs in the 30 to 50 age group, and women are 5 times more likely to be men. The bilateral incidence of about 1/3 to 1/2, bilateral incidence of female: male 9:1. Due to the compression of the median nerve, the thumb, food, and middle finger produce pain and numbness. In the early stage, it often manifests as sensory dysfunction at the fingertips. It often wakes up due to numbness or burning pain several hours after falling asleep, and relieves after the activity. A small number of patients have neurotrophic disorders due to long course of disease, large muscle muscle atrophy, intermittent skin whitening, cyanosis, severe cases of thumb, index finger cyanosis, fingertip necrosis or atrophic ulcer. During the examination, the center of the wrist can be slammed, causing numbness and pain in the median nerve innervation area. This is the Tinel sign. In some patients, the wrists were extremely flexed for 60 seconds, and the fingers felt abnormally aggravated. This was positive for the Phalen test. The use of a sphygmomanometer to pressurize the upper arm to the distal extremity of the vein can induce symptoms.

If carpal tunnel syndrome is suspected, the following tests should be performed to confirm the diagnosis:

1Tinel sign: Use the finger to slam the median nerve at the proximal edge of the wrist ligament. The thumb, food, and middle finger have positive radiation pain.

2 wrist test: the elbow rests on the table, the forearm is perpendicular to the tabletop, and the two wrists are naturally palmar. At this time, the median nerve was pressed to the proximal edge of the transverse carpal ligament, and the carpal tunnel syndrome quickly became painful.

3 Cortisone test: Hydrocortisone is injected into the carpal tunnel, and pain relief can help to confirm the diagnosis.

4 tourniquet test: inflation of the sphygmomanometer to 30 to 60 seconds above the systolic pressure can induce finger pain is positive.

5 Stretching wrist test: Maintaining the wrist in the over-extension position, and the pain is positive immediately.

6 acupressure test: positive pressure at the median nerve compression point near the lateral edge of the transverse ligament of the wrist with finger pressure can induce finger pain.

7 median nerve conduction velocity: normal, the median nerve from the proximal wrist transverse stripes to the thumb to the palm muscle or the thumb abductor muscle between the motor fiber conduction velocity is shorter than 5 microseconds. If it is longer than 5 microseconds, it is abnormal. Carpal tunnel syndrome can be up to 20 microseconds, indicating damage to the median nerve. Surgical treatment should be considered for conduction times greater than 8 microseconds.

Differential diagnosis

Differential diagnosis of carpal tunnel syndrome:

Many diseases can have symptoms similar to those of carpal tunnel syndrome, such as finger numbness, pain, and the like. Therefore, attention should be paid to identification to prevent misdiagnosis.

(1) The most important difference in differential diagnosis is the differentiation between peripheral neuritis and radiculopathy.

Peripheral neuritis is mainly numbness of the fingers, and the pain is mild. Most of them are hands, showing a symmetry-sensing disorder, and it is not difficult to identify.

(2) The identification of cervical spondylotic radiculopathy and carpal tunnel syndrome is very important. Both can have numbness and pain in the fingers, but the treatment is completely different. At the same time, the two may exist at the same time, that is, the same patient suffering from cervical spondylosis and carpal tunnel syndrome at the same time, need to be carefully distinguished, respectively, in order to achieve good results.

Cervical spondylotic radiculopathy is characterized by painful radiation that radiates from the neck and shoulders to the distal end. The patient has symptoms of the neck, shoulders, upper limbs and hands. Pain has a certain relationship with neck activity. Cervical X-ray and CT can show cervical degeneration. A wide range of pain and sensory disturbances. Electromyography can provide a basis for differential diagnosis. Carpal tunnel syndrome is characterized by nocturnal finger pain, positive pressure finger test, and electromyography examination of the median nerve conduction velocity from the proximal wrist transverse stripes to the large fish.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.