Carpal tunnel syndrome is a clinical syndrome that results in numbness, pain, and limited movement of the fingers due to compression or injury to the median nerve in the carpal tunnel. The disease is most often seen in middle-aged women. Occupations with heavy hand work and a wide range of wrist activities are prone to this disease. The incidence of carpal tunnel syndrome is higher in occupations such as farmers, housewives, laundry workers and milkmaids.
The main symptoms are the gradual appearance of abnormal sensations in the thumb, index finger and middle finger, such as tingling, burning pain, numbness and swelling. Nocturnal pain is its characteristic feature, which affects sleep. In the morning, the fingers are stiff and immobile.
On examination, it is seen that the radial side of the affected hand is accompanied by decreased sensation in the above three fingers and decreased hand strength. The thumb weakness is most prominent. Atrophy of the greater interosseous muscle and thumb-to-little finger impairment were observed. The skin of the hyperalgesic area is poorly nourished, dry and flaky.
Further tests should be performed to clarify the diagnosis when carpal tunnel syndrome is suspected as follows.
①Tinel’s sign. If the thumb, index and middle finger have radiating pain, it is positive.
② Wrist flexion test. Rest both elbows on the table with the forearms perpendicular to the table and both wrists naturally palmarly flexed. At this point, the median nerve is pressed against the proximal edge of the transverse carpal ligament, and pain soon appears in patients with carpal tunnel syndrome.
(iii) Cortisone test. Injecting hydrocortisone into the carpal tunnel can help confirm the diagnosis if the pain is relieved.
(iv) Tourniquet test. Inflating the sphygmomanometer above the systolic pressure for 30-60 seconds is considered positive if it can induce finger pain.
⑤ Wrist extension test. Maintaining the wrist in the hyperextended position and quickly developing pain is considered positive.
(6) Acupressure test. Finger pressure at the median nerve pressure point at the proximal margin of the transverse carpal ligament is considered positive if it can induce finger pain.
(vii) Median nerve conduction velocity. The conduction velocity of the median nerve from the proximal transverse carpal ligament to the thumb to palmar muscle or the short thumb extensor muscle is less than 5 microseconds when normal. If it is longer than 5 microseconds, it is abnormal. Carpal tunnel syndrome of up to 20 microseconds indicates damage to the median nerve. Surgical treatment should be considered for conduction times greater than 8 microseconds.
Treatment
① Conservative treatment of carpal tunnel syndrome
Conservative treatment is used in milder cases. First of all, the wrist joint should be kept at rest and can be immobilized with wrist brace or cast to limit the wrist joint activities and promote the decreasing of the edema of the tissues in the carpal tunnel. Physical therapy is effective in reducing swelling and relieving pain. Hydrocortisone acetate can also be used for local closure. However, it should not be done repeatedly or several times to avoid aggravating the injury.
②Surgical treatment of carpal tunnel syndrome
Patients with ineffective conservative treatment or multiple recurrences need surgical treatment. Patients with carpal tunnel syndrome due to fracture, dislocation or occupational lesions should also be treated surgically.
The transverse carpal ligament is surgically incised to decompress the median nerve. If there is a fracture or dislocation, an incision is made or the necessary orthopedic treatment is performed. If there is an occupying lesion, it should be removed.
Prevention of carpal tunnel syndrome
Carpal tunnel syndrome can be caused by a variety of etiologies. In most patients, it is caused by excessive hand and wrist movement. Prevention in patients with this type of cause is of interest. The significance lies not only in prevention before the onset of the disease, but also in prevention of recurrence after the symptoms have resolved. When the hand and wrist work is intensive, attention should be paid to resting between labors to prevent continuous pressure on the median nerve of the wrist. Middle-aged women should pay more attention to this point during labor. In addition, relaxing the wrist and fully moving the wrist joint before and after work can help prevent the occurrence of carpal tunnel syndrome. For patients who have already suffered from the disease, if their symptoms are relieved after treatment, care should be taken to prevent recurrence. It is important to avoid prolonged hand and wrist activities of high intensity. Patients with fractures and dislocations due to trauma who have numbness and pain in the fingers should go to the hospital for timely examination and treatment to obtain good results.