Is it carpal tunnel or arthritis?

Arthritis and carpal tunnel syndrome are different problems, and they can occur together. Arthritis is pain, stiffness and swelling in a joint. Carpal tunnel is numbness and tingling from a squeezed median nerve at the wrist. The two are also linked: a 2016 meta-analysis found that rheumatoid arthritis and osteoarthritis were both associated with carpal tunnel syndrome ¹. A clinician therefore checks for both rather than choosing one.

Joint pain and stiffness point to arthritis

Arthritis is a problem in the joint itself. One form felt in the hand is osteoarthritis at the base of the thumb, a wear-and-tear change that becomes more common with age. In a 2021 meta-analysis, 39.0 percent of 80-year-old women had radiographic thumb base osteoarthritis ², and the share rises with age.

Those figures count X-ray changes, and X-ray changes are common without pain. They show how often the joint wears, not how often it hurts enough to need treatment. Thumb base arthritis usually feels like an ache, stiffness, a weaker grip and sometimes a visible bump at the joint, and the ache is worse with gripping and pinching.

Numbness points to the nerve, not the joint

Carpal tunnel syndrome is excessive pressure on the median nerve at the wrist ³. Its main sign is numbness and tingling in the thumb, index, middle and ring fingers, often at night ⁴. The median nerve gives feeling to the thumb, index finger, middle finger and half of the ring finger ⁵.

So a numb hand that wakes you points to the nerve, and a sore, stiff joint that hurts when you grip points to arthritis. Many people have both, which is why the history and examination matter more than any single symptom.

Rheumatoid arthritis is linked to carpal tunnel syndrome

The link is an association, not a single cause. The 2016 meta-analysis found that rheumatoid arthritis was associated with carpal tunnel syndrome, with a pooled confounder-adjusted odds ratio of 1.96 ⁶. An odds ratio near 2 means roughly double the odds of carpal tunnel in people with the condition, in these observational studies. It does not show that arthritis causes carpal tunnel, and it does not predict any one person's risk.

MedlinePlus lists arthritis of the wrist among the factors that may lead to carpal tunnel syndrome, along with wrist fractures, obesity, pregnancy-related fluid retention and infections ⁷. The list names factors, not frequencies, so it tells you what to consider rather than how often each one causes the problem.

How a clinician tells them apart

A clinician examines the joints for swelling, tenderness and movement at the thumb base, and examines the hand for sensation, grip and the signs of nerve compression. Tests such as Phalen's and Tinel's can point toward carpal tunnel, but no single test is decisive. If the examination leaves doubt, nerve conduction testing can confirm carpal tunnel ⁸.

What to do

1. Sort the symptom. Numbness and tingling in the fingers point toward the nerve. Joint ache, stiffness and a bump point toward the joint. Write down which applies to each hand.
2. Note the timing. Night numbness that wakes you is typical of carpal tunnel. Joint pain that is worst after heavy use and eases with rest is typical of arthritis.
3. See a GP if the numbness persists, the grip weakens or the joint pain limits daily tasks. The NHS gives the advice to see a GP for carpal tunnel when symptoms worsen or do not go away ⁹.
4. Protect the joint and the nerve. Less pinching and gripping eases strain on both, and moving some typing to your voice means less typing for the thumb and wrist. Dictation for RSI and carpal tunnel explains how to switch parts of the work.

The treatments for the two conditions are different, so the diagnosis matters. The carpal tunnel treatment guide covers splints, injections and surgery for the nerve. For the full set of hand and wrist causes, see hand and wrist pain from typing, and for the wider subject, the accessibility and health overview. If the numbness is at the base of the thumb rather than in the joint, the de Quervain's comparison is the next question to check, and the carpal tunnel diagnosis question explains the tests in more detail.