A numb hand: the neck or the wrist?
Pressure on a nerve in the neck and at the wrist can both numb the hand, but the treatments differ. A few signs help you see what your doctor is looking for.
Tingling fingers are one of the most common reasons people have a neck MRI. Sometimes the cause is in the neck, and sometimes it is a long way down, at the wrist.
Carpal tunnel syndrome: pressure at the wrist
A nerve called the median nerve passes through a narrow tunnel in the wrist. When this tunnel swells, the nerve comes under pressure.
- Ache or pain in the fingers, hand or arm
- Numbness and tingling
- A weak thumb or trouble gripping
- A slow start, with symptoms that come and go
- Worse at night
It is more common in pregnancy, with excess weight, diabetes and arthritis, and in work that bends the wrist repeatedly or uses vibrating tools.
A nerve root in the neck
- Pain runs from the neck to the shoulder and arm
- Tingling in one arm together with neck or arm pain
- Worse with turning or bending the neck back, coughing and sneezing
- Sometimes pain between the shoulder blades
So how is it told apart?
Guessing from the internet will not give the answer. The doctor checks feeling, strength and reflexes and sees which nerve the pattern of numbness fits. A nerve conduction study (EMG and NCV) shows where the pressure is. Sometimes a patient has both problems at once.
The treatments differ
- Wrist: a night splint for up to about 6 weeks, less repetitive work, sometimes a steroid injection, and if it gets worse, a short operation under local anaesthetic.
- Neck: exercises, physiotherapy and medicines. Surgery comes up when these do not help or there is weakness.
When to go early
If both hands feel heavy, your hands lose co-ordination or your walking changes, pressure on the spinal cord is possible. Take these signs seriously.