Peripheral Mononeuropathy - Carpal Tunnel Syndrome

Question 1

Aetiology of Carpal Tunnel Syndrome.

Answer 1

Compression of Medial Nerve as it travels through the Carpal Tunnel in the Wrist.

Question 2

Anatomy of Carpal Tunnel.

Answer 2

1. Flexor Retinaculum/Transverse Carpal Ligament (Fibrous Band) across Palmar Side of Wrist.
2. Carpal Tunnel = Passage between Carpal Bones and Flexor Retinaculum.

Question 3

What can cause Compression of the Contents of the Carpal Tunnel? (2)

Answer 3

1. Swelling of Contents e.g. Tendon Sheaths - Repetitive Strain.
2. Narrowing of Tunnel.

Question 4

Sensory Branches of Median Nerve (2).

Answer 4

1. Palmar Digital Cutaneous Branch - sensory innervation of the palmar aspects and full fingertips of the lateral 3.5 fingers.
2. Palmar Cutaneous Branch - Sensation to Palm (branches before Carpal Tunnel).

Question 5

Motor Functions of Median Nerve (3).

Answer 5

3/4 Thenar Muscles at Base of Thumb :

1. Abductor Policies Brevis.
2. Opponens Pollicis.
3. Flexor Pollicis Brevis.
   * Adductor Pollicis = Ulnar Nerve (Thenar Muscle Though).

Question 6

Risk Factors of Carpal Tunnel Syndrome (7).

Answer 6

IDIOPATHIC : 
1. Repetitive Strain.
2. Obesity.
3. Perimenopause/Pregnancy.
BILATERAL : 
4. Rheumatoid Arthritis.
5. Diabetes.
6. Acromegaly.
7. Hypothyroidism.

Question 7

Clinical Presentation of Carpal Tunnel Syndrome.

Answer 7

1. Gradual Onset of Symptoms.
2. Worse at Night.
3. Intermittent Symptoms.
4. Shake = Relief.

Question 8

Sensory Symptoms (4).

Answer 8

1. Numbness.
2. Paraesthesiae.
3. Burning Sensation.
4. Pins.

Question 9

Examination - Special Tests of Carpal Tunnel Syndrome (2).

Answer 9

1. Phalen’s Test.

2. Tinnel’s Test.

Question 10

Survey in Carpal Tunnel Syndrome.

Answer 10

Kamath and Stothard Carpal Tunnel Questionnaire (CTQ) - predicts likelihood of diagnosis based on clinical presentations.

Question 11

Investigations of Carpal Tunnel Syndrome.

Answer 11

Diagnosis - Nerve Conduction Studies : Prolongation of Action Potential - both sensory and motor.

Question 12

Management of Carpal Tunnel Syndrome.

Answer 12

1. Rest/Altered Activities.
2. Wrist Splints to Maintain Neutral Position of Wrist at Night (4 Weeks at Least).
3. Steroid Injections.
4. Surgery.

Question 13

Surgery of Carpal Tunnel Syndrome.

Answer 13

Incision of Flexor Retinaculum under Local Anaesthetic as Open/Endoscopic Surgery to release pressure on Median Nerve.