Carpal tunnel: can it cause pain up to the shoulder?

Yes, carpal tunnel can cause pain above the wrist, up the forearm and sometimes as far as the shoulder. In a study of 159 people with confirmed carpal tunnel syndrome, more than a third had pain above the wrist (Stevens et al., Muscle & Nerve, 1999). But if your shoulder or neck hurts and your fingers go numb, it's worth ruling out the neck, because an irritated nerve root there causes very similar symptoms and is treated differently.

What carpal tunnel syndrome is

It's compression of the median nerve as it passes through the wrist, in a narrow channel formed by the wrist bones and a ligament. That nerve supplies feeling to the thumb, index, middle finger and half of the ring finger.

Typical symptoms

Tingling or numbness in the thumb, index, middle and part of the ring finger. The little finger is usually spared.
Worse at night or on waking, and better when you shake your hand.
Comes on when driving, holding your phone or reading with a book in your hand.
Clumsiness: dropping things, trouble with buttons.
In advanced cases, the muscle at the base of the thumb looks thinner.

Why can it hurt up to the shoulder?

There are three possible explanations, and telling them apart is what matters:

Referred pain from the carpal tunnel itself. The irritated nerve at the wrist can cause vague pain that travels up the forearm, the elbow and, less often, the shoulder. The tingling, though, stays in the fingers.
The source is the neck. An irritated nerve root at C6 or C7, for example from a cervical disc protrusion, causes neck and shoulder pain that travels down the arm to the same fingers.
Both at once. A nerve squeezed in the neck seems to become more sensitive to compression at the wrist, and having both problems isn't unusual.

Wrist or neck? Clues to tell them apart

More likely the wrist if:

Symptoms are worse at night and with your wrist bent.
Shaking your hand helps.
Your neck moves well and moving it changes nothing in your hand.

More likely the neck if:

There's neck pain or pain between the shoulder blades.
Turning or tilting your head back reproduces the pain or tingling in your arm.
The arm pain eases when you rest your hand on top of your head.
Symptoms also reach the back of the hand or the outer forearm.

The test that confirms it is a nerve conduction study, which your doctor can request.

Causes and risk factors

Repeated or sustained wrist movements: keyboard and mouse, vibrating tools, manual work.
Pregnancy, because of fluid retention. It usually improves after birth.
Diabetes, hypothyroidism and rheumatoid arthritis.
Excess weight.
It's more common in women and from the age of 40-50.

What helps

For mild and moderate cases, treatment starts without surgery:

A night splint that keeps the wrist straight. It's the simplest measure and the first one recommended.
Change how you use your hands: straight wrist when typing, a vertical mouse or one at elbow height, breaks every 30-45 minutes.
Gentle nerve and tendon gliding exercises, without triggering tingling.
A steroid injection, prescribed by a doctor, for short-term relief.
Surgery if there's weakness, thumb muscle wasting or symptoms that don't improve: it's a simple operation with good results.

How we treat it at the clinic

We examine the wrist, elbow, shoulder and neck, including sensation, strength and reflexes, to find where the problem starts. Then:

We mobilise the wrist, elbow and, if involved, the neck and upper back.
We teach you the nerve exercises and specific changes for your workstation.
If there are signs of advanced compression, we refer you to a doctor for a nerve conduction study.

The evidence for manual therapy in carpal tunnel is limited, so we use it alongside the splint and habit changes, not instead of them.

When to see a doctor

Weakness in the hand or thumb.
The muscle at the base of the thumb thinner than on the other hand.
Constant numbness that never goes away.
Symptoms in both hands with clumsiness or unsteadiness walking.
Left shoulder pain with chest tightness or breathlessness: call 112.

Frequently asked questions

Can carpal tunnel affect the shoulder? It can cause pain that reaches the shoulder, but it doesn't damage the shoulder. If your shoulder hurts a lot, have your neck and the shoulder itself checked too.

Why is it worse at night? We tend to bend our wrists in our sleep, which raises the pressure inside the tunnel. That's why a night splint helps.

Does it go away on its own? Sometimes, especially in pregnancy. If it lasts months or is getting worse, it's worth treating to avoid nerve damage.

Will any wrist support do? A splint that keeps the wrist straight is better than one that bends it back.

Can I keep using my computer? Yes, with changes to wrist position, mouse and breaks. See micro-stretches you can do at your desk.