Nerve Palsies & Carpal Tunnel Syndrome

Question 1

What is Carpal Tunnel Syndrome?

Answer 1

Compression of the median nerve as it travels through the carpal tunnel.

Also known as median nerve palsy.

Question 2

What muscles are affected by median nerve palsy? (4)

Answer 2

• Opponens Pollicis
• Flexor Pollicis Brevis
• Abductor Pollicis Brevis
• Lateral two Lumbricals

Question 3

What are the most common causes of Carpal Tunnel Syndrome? (5)

Answer 3

• Developmental
• Metabolic (pregnancy / mucopolysaccharides / hypothyroidism)
• Inflammatory ( Rheumatoid Arthritis / Gout / TB / Amyloid)
• Trauma (Distal Radius Fracture)
• Swellings (Ganglion / Fibroma / Lipoma)

Question 4

How does carpal tunnel syndrome usually present?

Answer 4

Nocturnal Pain and Parasthesia in the median nerve distribution.

Wasting of thenar muscles

Question 5

Examinations specifically for Carpal Tunnel Syndrome? (4)

Answer 5

• Tinel’s Test
• Phalen’s Test
• Visual examination (Thenar Wasting, Previous Scars & Deformities from fractures)
• Neurohysiology (sensation, movements and assessing APB power)

Question 6

What is the Tinel’s Test?

Answer 6

Tapping on the wrist to see if it induces tingling.

Question 7

What is the Phalen’s Test?

Answer 7

Maximal wrist flexion for ONE MINUTE to try illicit symptoms.

(Inverse prayer sign)

Question 8

What treatments are available for Carpal Tunnel Syndrome? (3)

Answer 8

Wrist Splinting
Local Corticosteroid Injection
Carpal Tunnel Release (Decompression Surgery)

Question 9

What is Radial Nerve Palsy?

Answer 9

Entrapment or compression of the radial nerve.

Question 10

What are the symptoms of Radial Nerve Palsy?

Answer 10

Axilla:

• Loss of elbow extension
• Loss of wrist extension (wrist drop)
• Sensory changes in forearm and hand

Arm:

• Loss of wrist extension
• Sensory loss

Forearm:
- Loss of finger extension (posterior interosseous nerve specifically)

Wrist:
- Loss of sensation (superficial radial nerve)

N.B. Symptoms depend on the site of the lesion