Carpal tunnel syndrome
Compression of the median nerve as it passes through the carpal tunnel at the wrist, producing numbness, tingling, and night pain in the thumb, index, middle and radial half of the ring finger.
📊 Carpal tunnel syndrome is the most common nerve compression syndrome in the upper limb, affecting around 3-5% of adults at some point in their lifetime. It is more common in women than men.
What is carpal tunnel syndrome?
The carpal tunnel is a narrow passage on the palm side of the wrist, formed by the small bones of the wrist below and a strong band of tissue (the transverse carpal ligament) above. Running through this tunnel are nine tendons that bend the fingers, and one important nerve, the median nerve, which supplies feeling to the thumb, index, middle and half the ring finger, and powers some of the small muscles at the base of the thumb.
In carpal tunnel syndrome the pressure inside this tunnel rises, squeezing the median nerve. Early on this causes tingling and numbness, classically worse at night and on waking. Many people describe shaking the hand to relieve symptoms. Over time, if pressure on the nerve continues, the nerve fibres can be damaged, leading to permanent numbness and weakness or wasting of the thumb muscles.
Most cases are idiopathic, meaning there is no single clear cause, but it is strongly associated with pregnancy, diabetes, thyroid disease, rheumatoid arthritis, obesity, and occupations involving forceful repetitive gripping or prolonged vibration exposure.
Common causes
- Idiopathic (most cases, no single cause identified)
- Pregnancy (often resolves after delivery)
- Diabetes and thyroid disorders
- Rheumatoid arthritis and other inflammatory conditions
- Wrist fracture or significant wrist deformity
- Repetitive forceful gripping or vibrating tool use
- Obesity
Who is at risk? Female sex, age 40-60, pregnancy, diabetes, obesity, hypothyroidism, and certain occupations involving sustained wrist flexion or vibrating tools are the main risk factors. A family history is also common.
Symptoms
Symptoms vary depending on the severity and duration of the condition. Common symptoms include:
- Tingling and numbness in the thumb, index, middle and radial half of the ring finger
- Symptoms worse at night, often waking the patient from sleep
- Pain or aching in the hand that may radiate up the forearm
- Need to shake the hand or hang it over the bed edge to relieve symptoms
- Clumsiness, dropping objects, difficulty with fine tasks such as buttons
- In advanced cases: wasting of the muscle bulk at the base of the thumb (thenar wasting)
When to seek help: See your GP or hand specialist if symptoms wake you at night, if numbness is becoming constant rather than intermittent, or if you notice any weakness or muscle wasting in the thumb. Persistent numbness can lead to permanent nerve damage if left untreated.
How is it diagnosed?
Your hand surgeon will take a detailed history and examine the hand and wrist. The following investigations may be arranged to confirm the diagnosis:
- Clinical examination, Phalen test, Tinel sign at the wrist, Durkan compression test
- Assessment of sensation in the median nerve distribution
- Assessment of thumb abduction strength and thenar muscle bulk
- Nerve conduction studies, the gold standard, grading severity from mild to severe
- Ultrasound, increasingly used to assess median nerve cross-sectional area
Nerve conduction studies are recommended before surgical decompression in most cases. They confirm the diagnosis, grade severity, and exclude other causes of similar symptoms such as cervical radiculopathy or generalised peripheral neuropathy.
Treatment pathway
Treatment is tailored to the severity of the condition, your age, activity level, and overall health. Most conditions are treated in a stepwise fashion, starting with the least invasive options.
Night splinting and activity modification
A wrist splint worn at night keeps the wrist in a neutral position and reduces pressure in the carpal tunnel. Many patients improve significantly within 6 weeks. Activity modification, reducing prolonged wrist flexion and adjusting workstation ergonomics, supports this.
Corticosteroid injection
A single injection of corticosteroid into the carpal tunnel can provide substantial symptom relief, sometimes lasting many months. It is useful diagnostically and as a temporising measure. Repeated injections are generally not recommended.
Carpal tunnel release
Surgical division of the transverse carpal ligament, performed either open through a small palmar incision or endoscopically. It is one of the most successful operations in surgery, with rapid relief of night symptoms in the great majority of patients. Done under local anaesthetic as a day-case procedure.
Recovery
After carpal tunnel release, night symptoms usually settle within days. The wound is sore for one to two weeks and the palm may feel tender (pillar pain) for several months. Grip strength dips initially and returns to normal, or stronger, by three months. Permanent numbness present before surgery may not fully recover.
- Splinting trial: 4-6 weeks
- Return to light activity after surgery: 1-2 weeks
- Heavy gripping and lifting: 4-6 weeks
- Full recovery of grip strength: 2-3 months
What results can I expect?
Excellent in most cases. Around 90% of patients are highly satisfied with surgical release. Outcomes are best in those with mild-to-moderate disease; long-standing severe disease with established muscle wasting has more limited recovery of nerve function.
In numbers
Typical activity timelines for this condition. These are approximate and vary considerably between patients. Always follow the specific guidance given by your surgeon and hand therapist.
| Activity | Typical timeline | Notes |
|---|---|---|
| Drive | 1-2 weeks after surgery | When you can grip the wheel comfortably and perform an emergency stop. Inform your insurer. Automatic / left-handed driving may be earlier if right-handed.[3] |
| Shower | When dressing is waterproof | Most patients keep the dressing dry for 10-14 days until the wound has healed.[2] |
| Light desk work | 2-3 days after surgery | Many patients return to office-based work within days. Keep the hand elevated and take rest breaks for the first week.[2] |
| Manual work | 4-6 weeks after surgery | Heavy gripping, lifting, and tools usually wait until the wound has settled and grip strength returns.[2] |
| Sport | 6-8 weeks after surgery | Non-contact activities earlier, contact sports later. Be guided by grip strength and comfort. |
| Lift heavy objects | 4-6 weeks after surgery | Pillar pain (tenderness at the base of the palm) is common for the first few weeks and limits gripping comfort.[2] |
| Full grip strength | 2-3 months | Grip and pinch strength continue to improve gradually after the wound has healed. Most patients reach near-pre-symptom strength within 3 months.[2] |
Common concerns from patients with this condition or recovering from treatment, and whether they are expected or worth mentioning to your team.
- 1.NICE CKS: Carpal tunnel syndrome (clinical knowledge summary)
- 2.British Society for Surgery of the Hand: Carpal tunnel syndrome patient information
- 3.Royal College of Surgeons of England: Driving after surgery guidance
- 4.British Association of Hand Therapists: Patient information leaflets
- 5.NHS: Carpal tunnel syndrome
References are to UK clinical guidance and patient information from recognised organisations. This page is for general information and does not replace personalised advice from your own clinical team.
Going to have surgery?
If your team has recommended an operation for this condition, our step-by-step prep guide covers what to expect.
Hand therapy guide
Phased exercise programme, key precautions, and what to expect from rehabilitation for this condition.
How is it diagnosed?
- ✓Clinical examination, Phalen test, Tinel sign at the wrist, Durkan compression test
- ✓Assessment of sensation in the median nerve distribution
- ✓Assessment of thumb abduction strength and thenar muscle bulk
- ✓Nerve conduction studies, the gold standard, grading severity from mild to severe
- ✓Ultrasound, increasingly used to assess median nerve cross-sectional area
Recovery milestones
- •Splinting trial: 4-6 weeks
- •Return to light activity after surgery: 1-2 weeks
- •Heavy gripping and lifting: 4-6 weeks
- •Full recovery of grip strength: 2-3 months