Index Finger Numbness

Numbness in index finger can be triggered due to squeezing or pressing of median nerve, which performs work of providing sensation and impulses to the palm and wrist for movement. Carpal tunnel is a narrow ligament passage or tunnel containing median nerve. Slight inflammation can press the nerve, resulting in tingling and numbness with finger joint pain.

Repetitive wrist and hand motion, as in typing, is the most common cause of tingling and numbness in fingers. Many people are used to typing on the keyboard with index finger, which is a prominent cause of numbness and tingling in index finger.

Activities such as painting, playing musical instruments, driving, and excessive writing which require continuous and repeated use of wrist and hand also lead to finger pain and loss of sensation. Squeezing of median nerve is the main reason initiating this condition. This leads to loss of sense of touch and loss of movement.

• Rheumatoid arthritis: Rheumatoid arthritis is defined as an inflammatory disorder targeting synovial joints. It causes tendon inflammation which leads to the condition.
• Hypothyroidism: Hypothyroidism is a disorder marked by under active thyroid gland. It leads to swelling of hands and feet, which causes numbness in hands and feet.

• Lyme borreliosis: Lyme disease is an infective disease caused due to borrelia bacteria. It affects the nervous system, thus causing the person to feel numb in the fingers and wrist.
• Nerve compression: If the nerve connecting the central nervous system and the arm gets compressed, it triggers left arm numbness at night.

The symptoms such as tingling in arms is most common. The person feels acute pain in wrist and palms. The fingers affected with tingling may vary from person to person. For instance, a left-handed writer having carpal tunnel syndrome would experience numbness, since his/her left hand is put more into use for repeated and continuous writing activity. 

Symptoms include dexterity problems like clumsiness and difficulty in gripping things. Keeping hands in the same position for a long time worsens the symptoms which are often aggravated at night. Muscle atrophy of thumb is a common symptom for numbness in thumb and index finger. Rarely, inflammation with change in skin color in the affected area is seen.

For diagnosis, the doctor looks for the causes and signs such as poor hand grip, numbness in index finger, middle finger, thumb, or wrist. If tapping the wrist above median nerve causes pain extended from wrist through hand, it hints at compression of median nerve. Phalen's test can also detect the cause for the condition.

In Phalen's test, a person is made to twist the wrist for a minute. If it causes weakness or numbness, it indicates that this condition is due to median nerve compression. The tests that may have to be done include electromyography, wrist X-ray, and nerve condition velocity.

In electromyography, a thin needle electrode is admitted through the arm muscle. The electrode collects the response of muscles on bending the arm and the image is displayed on oscilloscope. The doctor can diagnose the disorder by the image.

In nerve condition velocity, a mild electrical impulse is given to arm nerves through surface electrodes or patches, and the speed of the nerve signals is observed. Treatment includes wearing wrist splints to curb median nerve compression. It takes about 2 months to alleviate the symptoms after wearing splints.

If the symptoms do not subside within 3 months, the doctor may prescribe corticosteroid to reduce tendon swelling. Easy remedies like changes in posture while performing activities like typing can help ease the symptoms. If the cause is among the disorders discussed earlier, then treatment to alleviate the symptoms of that particular disorder is initiated.

Disclaimer: This is for informative purposes only, and should not be used as a replacement for expert medical advice.