Carpal Tunnel Syndrome
Carpal tunnel syndrome occurs when the median nerve is compressed within a narrow canal on the palm side of the wrist. It is the most common nerve compression condition. Its distinguishing feature is that it wakes people at night with numb hands, which is relieved by shaking the hand.
What Is the Carpal Tunnel?
At the wrist, a strong ligament (the transverse carpal ligament) covers the half-ring formed by the bones. Through the resulting tunnel pass nine finger tendons together with the median nerve. The walls of the tunnel do not stretch; when the volume inside increases or the tunnel narrows, pressure rises and the most sensitive structure — the nerve — is affected.
The median nerve carries sensation from the thumb, index finger, middle finger and half of the ring finger. The little finger not being affected is a typical clue; if the little finger is also numb, other causes are investigated.
Risk Factors
- Repetitive wrist movements and use of vibrating tools
- Pregnancy (related to fluid retention; often settles after delivery)
- Diabetes, thyroid disorders, rheumatological conditions
- Narrowing of the tunnel after a wrist fracture or osteoarthritis
- Excess weight
Symptoms
- Night numbness: waking with a numb hand, relieved by shaking it
- Numbness, tingling or burning in the thumb, index and middle fingers
- Numbness while driving, holding a phone or holding a newspaper
- Loss of dexterity in fine tasks: threading a needle, doing up buttons, picking up coins
- In advanced cases, wasting of the muscle at the base of the thumb and reduced grip strength
Symptoms are initially limited to the night but may spread into the daytime. Muscle wasting and constant numbness are findings for which assessment should not be delayed.
Diagnosis
- History: distribution of the numbness, waking at night, occupational and pregnancy history, accompanying conditions.
- Examination: sensory examination, strength at the base of the thumb, Tinel and Phalen tests.
- Nerve conduction studies (EMG): show the presence and degree of compression; particularly valuable if surgery is being considered.
- Ultrasound: may be used to assess the thickness of the nerve and the structures within the tunnel.
In the differential diagnosis cervical disc herniation matters; nerve compression arising from the neck can cause similar numbness. In some patients both are present together.
Treatment
Non-surgical treatment
In mild and moderate cases the first approach is not surgical.
- Night splint: holds the wrist in a neutral position, reduces pressure within the tunnel and can markedly reduce night numbness
- Reducing repetitive forceful movements and use of vibrating tools; reviewing working arrangements
- Nerve gliding exercises
- Managing accompanying conditions (diabetes, thyroid disease)
- Injection treatment in selected cases
In carpal tunnel syndrome developing during pregnancy the non-surgical approach is the first preference; symptoms often settle after delivery.
Surgical treatment
In surgery the ligament covering the tunnel is released to make room for the nerve. Surgery is considered in patients who do not respond to non-surgical treatment, in whom nerve studies show advanced compression, and in those with constant numbness or muscle wasting.
Relief of night numbness is generally noticed early; by contrast, recovery of sensation and strength may be slower where the nerve has been compressed for a long time. Outcomes vary from person to person.
When Should You Seek Assessment?
- If you wake at night with numb hands
- If the numbness continues during the day
- If your dexterity in fine tasks has decreased or you drop things
- If you have noticed thinning at the base of your thumb
- If symptoms are increasing despite a splint and adjustments
When to Seek Medical Help Without Delay
- Sudden, rapidly increasing numbness and severe pain after a wrist injury
- Coldness, colour change or absence of a pulse in the hand
- Rapidly progressing muscle wasting and marked loss of strength
These findings require urgent assessment. Outside office hours, go to the nearest emergency department.
Frequently Asked Questions
Can carpal tunnel syndrome settle without surgery?
In mild and moderate cases symptoms can decrease markedly with a night splint, activity modification and exercise. Where compression is advanced, numbness is constant or there is muscle wasting, less benefit is expected from non-surgical treatment.
Why is it particularly bad at night?
During sleep most people hold the wrist in a bent position, and pressure within the tunnel rises in that position. Fluid distribution also changes at night. A night splint is therefore among the first steps in treatment.
My little finger is numb too — is it carpal tunnel?
The median nerve does not supply sensation to the little finger. If the little finger is numb, compression of the ulnar nerve at the elbow or a problem arising from the neck is considered; examination and, if needed, nerve studies make the distinction.
It started in pregnancy — will I need surgery?
Carpal tunnel syndrome developing in pregnancy is often related to fluid retention and settles after delivery. During this period the priority is a splint and activity modification; surgery does not generally arise.
When can I use my hand after surgery?
Light daily use is generally resumed early; grip strength returning fully and tenderness at the wound settling take time. Your physician determines the exact timeframe according to your recovery.
Does using a computer cause carpal tunnel syndrome?
The evidence that keyboard use alone is a main cause is debated. Use of vibrating tools and forceful repetitive wrist movements are more strongly associated. Reviewing working arrangements is nevertheless recommended.
Academic Work
Assoc. Prof. Bertan Cengiz, MD has scientific work published in national and international peer-reviewed journals in the field of hand and wrist surgery and related areas. The publication list and verifiable academic sources are available on the Publications page.
Related Pages
- Hand and Wrist Surgery
- Cervical Disc Herniation (Neck Hernia)
- Trigger Finger
- Wrist Arthroscopy
- Tennis Elbow and Golfer’s Elbow (Epicondylitis)
The information on this page is for general guidance and does not replace an in-person medical examination. Diagnosis and treatment require a physician’s clinical assessment. Outcomes of any treatment or surgical intervention may vary from person to person; no guarantee of a specific result or timeframe is given on this page.