Carpal tunnel syndrome

• What is Carpal Tunnel Syndrome
• Statistics on Carpal Tunnel Syndrome
• Risk Factors for Carpal Tunnel Syndrome
• Progression of Carpal Tunnel Syndrome
• Symptoms of Carpal Tunnel Syndrome
• Clinical Examination of Carpal Tunnel Syndrome
• How is Carpal Tunnel Syndrome Diagnosed?
• Prognosis of Carpal Tunnel Syndrome
• How is Carpal Tunnel Syndrome Treated?
• Carpal Tunnel Syndrome References

What is Carpal Tunnel Syndrome

Carpal tunnel syndrome (CTS) is a common painful disorder caused by compression of the median nerve within the wrist. CTS is characterised by pain, numbness and weakness in the parts of the hand supplied by the median nerve. People with CTS may complain of “pins and needles” in the thumb, index and middle fingers, and half of the ring finger, as well as pain in the wrist.
The carpal tunnel is a narrow, rigid passageway of ligament and bones below the wrist at the heel of the hand which houses the median nerve and tendons. The carpal tunnel is normally quite snug, and there is just enough room in it for the tendons and nerves that have to pass through it. If anything takes up extra room in the canal (such as inflammatory swelling or injury), the nerve in the canal becomes compressed or “pinched”. This leads to CTS symptoms.

Statistics on Carpal Tunnel Syndrome

CTS is a common condition that occurs in 2.7% of the general population. It is more common in women than men, and the average age of people with CTS is 40–50 years.

Risk Factors for Carpal Tunnel Syndrome

A specific cause for CTS is rarely identified. However, a variety of risk factors may contribute to the development of the condition:

• Heredity: Approximately 50% of the risk is determined in the genes
• Overuse, work situations requiring rapid finger and wrist motions
• Wrist injury
• Diabetes mellitus
• Pregnancy and fluid accumulation states
• Hypothyroidism
• Rheumatoid arthritis and other joint disorders
• Menopause
• Acromegaly
• Systemic inflammation
• End-stage renal disease and dialysis

Progression of Carpal Tunnel Syndrome

Carpal tunnel syndrome often starts with “pins and needles“, impaired sensation, or diminished sensation. The skin of the palm is usually unaffected.
With time, often there is progressive loss of coordination and strength in the thumb, and difficulty performing fine movements of the thumb as well as fine movements of the first to third digits.
With more persistent and severe squeezing or compression of the nerve, there may be wasting of some muscles of the hand.

How is Carpal Tunnel Syndrome Diagnosed?

The symptoms of nocturnal pain and numbness in the affected hand, as well as clinical signs, point towards diagnosis. A nerve conduction study is very useful to help confirm the diagnosis.
Blood tests may be useful to rule out other associated conditions (e.g. diabetes, rheumatoid arthritis, thyroid disease).
Imaging studies are sometimes required. X-rays are only of value in the presence of evidence of injury, fracture or bone changes. Ultrasound is occasionally used.

Prognosis of Carpal Tunnel Syndrome

Prognosis with surgery is very good, with 90% of patients obtaining long lasting relief from CTS symptoms.

How is Carpal Tunnel Syndrome Treated?

The management of carpal tunnel syndrome depends on the cause.

• Resting the wrist for a period of time in a wrist splint may help all causes.
• Physical therapy.
• For work-related CTS: Modifying activities and work habits.
• Anti-inflammatory medications; steroid injection into the wrist.
• Treating a related medical condition that may be causing CTS symptoms.
• Surgery to release the carpal tunnel has a high rate of success in most cases.

Article kindly reviewed by:
Associate Professor Karl Ng MB BS (Hons I) FRCP FRACP PhD CCT Clinical Neurophysiology (UK) Consultant Neurologist – Sydney North Neurology and Neurophysiology (download referral form and map); Conjoint Associate Professor – Sydney Medical School, University of Sydney; and Editorial Advisory Board Member of the Virtual Neuro Centre.

Carpal Tunnel Syndrome References

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