Wrist/Hand: Carpal Tunnel Syndrome

Question 1

Definition

Answer 1

Carpal tunnel syndrome refers to the symptom complex brought on by compression of the median nerve in the carpal tunnel

Question 2

Aetiology

Answer 2

• Symptoms are caused by compression of the median nerve as it runs through the
carpal tunnel
• Usually IDIOPATHIC

Question 3

Symptoms may be secondary to:

Answer 3

May be SECONDARY to:

o Tenosynovitis (e.g. in rheumatoid arthritis)
o Infiltrative diseases of the canal/increased soft tissue (e.g. amyloidosis,
acromegaly)
o Bone involvement in the wrist (e.g. osteoarthritis, fracture)
o Fluid retention states (e.g. pregnancy, nephrotic syndrome)
o Other (e.g. obesity , menopause, diabetes)

Question 4

Epidemiology

Answer 4

• Prevalence: 2.7%

* Lifetime risk of 10%

Question 5

Presenting symptoms

Answer 5

• Tingling and pain in the hand and fingers

* Weakness and clumsiness of the hand

Question 6

Signs on physical examination

Answer 6

• Sensory impairment in the median nerve distribution
• Weakness and wasting of thenar eminence
• Tinel’s Sign - tapping the carpal tunnel causes symptoms
• Phalen’s Test - flexion of the wrist for 1 min may cause symptoms

• Look out for signs of the underlying cause (e.g. acromegaly, hypothyroidism)

Question 7

Investigations

Answer 7

• Bloods
o TFTs
o ESR

• Nerve Conduction Study (not usually necessary)
o Shows impaired median nerve conduction across the carpal tunnel