Carpal Tunnel Syndrome

Key facts

What carpal tunnel syndrome is

The carpal tunnel is a passage at the base of the palm, floored by the wrist bones and roofed by a thick ligament. Nine tendons and the median nerve share it. Anything that swells the tendon linings or narrows the tunnel squeezes the nerve, and the nerve responds first with tingling and numbness, later with pain and weakness. The median nerve supplies feeling to the thumb, index, middle and half of the ring finger, and power to the muscles that bring the thumb across the palm, which is why those are the areas affected.

It is the most common nerve entrapment in the body, roughly three times more common in women, and peaks between 40 and 60. Nighttime symptoms come from sleeping with the wrist bent, which raises pressure inside the tunnel; shaking the hand to get feeling back on waking is such a consistent story that it has a name, the flick sign.

Common causes and the neck connection

• Wrist position and use. Sustained or repetitive flexion and extension, forceful gripping, and vibrating tools. Keyboard work is a weaker risk factor than most people assume, but wrist posture at the keyboard matters.
• Medical conditions. Diabetes, hypothyroidism, rheumatoid arthritis, kidney failure and obesity all raise the risk. In diabetics, carpal tunnel syndrome is often layered on top of diabetic neuropathy, and both need to be recognized.
• Pregnancy. Fluid retention in the third trimester causes carpal tunnel symptoms in a large share of pregnancies; most resolve within weeks of delivery, so splinting is the usual treatment and surgery is almost never needed.
• Anatomy and injury. A small tunnel, a prior wrist fracture, a ganglion cyst or a mass inside the tunnel.

Double crush. A nerve that is already irritated at one point is more vulnerable to compression at another. A pinched C6 or C7 nerve root in the neck (cervical radiculopathy) and carpal tunnel syndrome coexist far more often than chance would predict, and treating only the wrist in that situation leaves symptoms behind. Neck pain, symptoms that reach above the elbow, tingling that changes with neck position, or a nerve study that shows only mild wrist findings despite significant symptoms all raise the question. This overlap is where a pain practice adds the most value, and our cervical radiculopathy page covers the neck side of it.

Symptoms and how it differs from look-alikes

Classic carpal tunnel syndrome: tingling and numbness in the thumb, index and middle fingers, sparing the little finger; worse at night and when holding a phone, steering wheel or book; relieved by shaking the hand; later, clumsiness and dropping things, aching into the forearm, and finally constant numbness.

• Versus cervical radiculopathy: neck and shoulder-blade pain, symptoms reaching above the elbow, tingling in a pattern that follows one nerve root (C6: thumb and index; C7: middle finger; C8: ring and little fingers), changes with neck position, and sometimes reflex changes.
• Versus cubital tunnel syndrome (ulnar nerve at the elbow): numbness in the ring and little fingers, worse with the elbow bent, weakness spreading the fingers.
• Versus peripheral neuropathy: numbness in all fingers of both hands and in the feet, in a glove-and-stocking pattern, usually with diabetes or another systemic cause. See peripheral neuropathy.
• Versus thumb arthritis or tendinitis: pain at the base of the thumb with pinching and gripping, without numbness.
• Versus Raynaud's or vascular problems: color change of the fingers with cold, rather than numbness at night.

How we diagnose it

History and examination. The pattern above is often enough for a clinical diagnosis. On exam we map exactly which fingers are numb, test thumb strength and look for thenar wasting, and perform provocation tests: tapping over the nerve at the wrist (Tinel's sign), holding the wrists flexed for 60 seconds (Phalen's test) and pressing directly over the tunnel for 30 seconds (Durkan's compression test), which is the most accurate of the three. We also examine the neck, shoulder and elbow and test reflexes to look for a second site of compression.

Nerve conduction studies and EMG. These measure how fast signals travel across the wrist and whether the thumb muscles show nerve damage. They confirm the diagnosis, grade it as mild, moderate or severe, and detect a coexisting cervical radiculopathy or neuropathy. We recommend them before any injection or surgical referral, and surgeons generally require them. Grade guides treatment: mild disease is splinted, moderate is injected, and severe disease (absent sensory response or motor involvement) goes to a surgeon.

Ultrasound of the median nerve at the wrist, where a swollen cross-sectional area supports the diagnosis and can reveal a cyst or mass, and guides injections. Cervical MRI only when the exam or nerve study suggests the neck is contributing.

Treatment options, in order

The sequence is splint, then injection, then surgery, and the American Academy of Orthopaedic Surgeons guideline supports each step. How fast you move through it depends on severity.

1. Night splint and activity changes (mild disease; first 4 to 6 weeks)

   A wrist splint that holds the wrist straight (neutral, not cocked back), worn every night and during provoking activities, relieves symptoms in most mild cases within 4 to 6 weeks and is the treatment of choice in pregnancy. Adjust keyboard and tool grip so the wrist stays neutral, take short breaks from repetitive gripping, and treat any underlying thyroid disease or diabetes. Oral NSAIDs, diuretics and vitamin B6 have not been shown to work and are not recommended.

2. Carpal tunnel steroid injection (moderate disease, or mild disease not controlled by splinting)

   A small dose of corticosteroid injected into the tunnel beside the nerve, ideally under ultrasound guidance to avoid the nerve. In randomized trials it relieves symptoms in the majority of patients at one month, with relief typically lasting 2 to 6 months and sometimes far longer; about a third of patients get durable relief from one injection. A good response also confirms the wrist, not the neck, as the source. We generally give no more than 2 injections in a wrist before recommending surgical evaluation, because repeated steroid can weaken tendons and delaying surgery in progressive disease risks permanent numbness. This is a treatment.

3. Treat the neck when it is contributing

   When nerve studies and exam show cervical radiculopathy alongside carpal tunnel syndrome, we treat both: physical therapy, medication and, for the neck, a cervical epidural steroid injection or selective nerve root block, described on the cervical radiculopathy page. Treating the wrist alone in a double-crush patient often disappoints. Learn more →

4. Hand surgery referral (severe disease, or failure of the steps above)

   Carpal tunnel release cuts the ligament roofing the tunnel to take pressure off the nerve. It is a 15- to 20-minute outpatient operation, open or endoscopic, with success rates around 90 percent and a low complication rate. We refer promptly for thenar atrophy, constant numbness, weakness, severe nerve studies, or symptoms that return after two injections. Numbness that has been constant for many months may improve only partially even after surgery, which is why we do not delay that referral.

What you can do now

• Buy an over-the-counter wrist splint that keeps the wrist straight and wear it every night for 4 to 6 weeks; most drugstore splints angle the wrist back and should be flattened or replaced.
• Keep the wrist neutral at the keyboard: elbows at 90 degrees, forearms supported, keyboard flat.
• Loosen your grip on the steering wheel, phone and tools, and take a 1-minute break from repetitive gripping every 20 to 30 minutes.
• Nerve-gliding exercises (fingers straight, wrist back, then relax) a few times a day may reduce symptoms in mild cases.
• Look at the base of your thumb in a mirror: if the muscle pad looks flatter than the other side, do not wait for an appointment with us; see a hand surgeon.
• Bring any nerve study report, prior injection dates and neck imaging.

Gulf Coast Pain & Spine evaluates carpal tunnel syndrome and its neck look-alikes at our Houston and Webster offices, and in Pearland once that office opens in November 2026.

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