Carpal tunnel syndrome

Further reading & learning

This website does not aim to educate staff on how best to examine and manage their caseloads but we appreciate staff may wish to explore further reading and the following has been provided for that reason.  We are unable to keep on top of the ever changing landscape in a timely enough manner to keep this corner of the site absolutely up to date so please do refer to other learning avenues as needed. 

Carpal Tunnel Syndrome Supporting Information for GPs

Presentation

• Pins & needles and/or numbness or burning sensation or pain in Median Nerve distribution
• Pain may radiate up wrist/arm
• Initially night/early morning though with time in day also
• Symptoms often relieved or improved by shaking/moving hand
• Weakness may occur especially of thumb grip
• History of dropping things and clumsiness of fine finger function may follow
  Median Nerve Distribution
• Wide variation in distribution but little finger is almost always excluded
• Palm is usually supplied by a superficial branch of the median nerve which bifurcates
  proximal to the carpal tunnel hence the palm may be spared also
• Supplies Opponens Pollicis/ abductor Pollicis Brevis which form the Thenar
  eminence hence wasting can occur

Differential diagnosis

• Other nerve entrapment syndromes such as cervical radiculopathy (C6/7) or ulnar nerve compression
• Peripheral Neuropathies especially diabetes
• Demyelinating disorders
• Repetitive strain Injuries (RSI) and work related upper limb disorders (WRULD)

Associations (more likely if symptoms bilateral)

• Hypothyroidism
• Rheumatoid Disease
• Diabetes Mellitus
• Pregnancy
• Previous Colles’ fracture
• Use of vibrating tools
• Amyloidosis
• Acromegaly

Prevalence

• 3% of females and 2% of males in population
• Peak age is 55yrs
• Family history (1 in 4 patients have 1st degree relative)

Diagnostic Tests and Signs

CTS can be confidently diagnosed by history alone in many patients.

1. Scored Questionnaire

The scored questionnaire developed by Levine et al was validated for diagnosis of CTS. The positive predictive value of the questionnaire is 90% (compared with 92% for nerve conduction studies)

2. Clinical tests (of confirmatory value only)
Phalens Test-Flex wrist for 60 seconds and occurrence of pain/paraesthesia is positive.

Tinel’s sign-Tap over median nerve at wrist, distal paraesthesia is positive.

3. Nerve conduction studies.  Gold standard investigation though does have false negative rate estimated at 10%

In view of sensitivity of scoring questionnaire NCS can be reserved for atypical cases

4. Other investigations

In some patients (eg those with bilateral symptoms or additional clinical suspicion) consider Thyroid function test and Glucose

Treatment Options

• Simple analgesia- there is no evidence that NSAIDS or diuretics are of any benefit over placebo
• Modification of activity- relevant to all patients but especially where RSI component or work related problem. This may include assessment/adaption of work- station set up.
• Night splinting-splinting in neutral position shown to be helpful to some degree in 80% of cases
• Local Corticosteroid injection- shown in RCT’s to give relief in 77% of patients at one month and 50% at a year.

Surgery-where other treatments fail or as a first line treatment where muscle wasting or permanent sensory deficit exist at presentation