Carpal tunnel syndrome

Question 1

Define carpal tunnel syndrome

Answer 1

Symptom complex brought on by compression of the median nerve in the carpal tunnel

Question 2

Aetiology of carpal tunnel syndrome

general +2

Answer 2

Symptoms caused by compression of median nerve as it runs through the carpal tunnel

Usually IDIOPATHIC
May be SECONDARY

Question 3

Aetiology of carpal tunnel syndrome - secondary

5

Answer 3

Tenosynovitis - e.g. in rheumatoid arthritis

Infiltrative diseases of the canal/increased soft tissue - e.g. amyloidosis, acromegaly

Bone involvement in the wrist - e.g. osteoarthritis, fracture

Fluid retention states - e.g. pregnancy, nephrotic syndrome

Other - e.g. obesity, menopause, diabetes

Question 4

Epidemiology of carpal tunnel syndrome

prevalence + lifetime risk

Answer 4

2.7% prevalence

10% lifetime risk

Question 5

Presenting symptoms of carpal tunnel syndrome

2

Answer 5

Tingling & pain in hand & fingers

Weakness & clumsiness of the hand

Question 6

Signs of carpal tunnel syndrome on physical examination

5

Answer 6

Sensory impairment in the median nerve distribution
Weakness & wasting of thenar eminence
Tinel’s sign - tapping carpal tunnel causes symptoms
Phalen’s test - flexion of wrist for 1 min may cause symptoms
Look out for signs of underlying cause

Question 7

Investigations for carpal tunnel syndrome

2

Answer 7

Bloods

Nerve conduction study

Question 8

Investigations for carpal tunnel syndrome - bloods

2

Answer 8

TFTs

ESR

Question 9

Investigations for carpal tunnel syndrome - nerve conduction study
(2)

Answer 9

Not usually necessary

Shows impaired median nerve conduction across carpal tunnel