Carpal tunnel syndrome Flashcards
What forms the carpal tunnel?
Flexor retinaculum
Carpel bones - base
What is the contents of the carpal tunnel?
9 tendons- 4 flexor digitorum superficialis, 4 flexor digitorum profundus, 1 flexor pollicis longus
1 nerve - Median nerve
What are the nerve roots of the Median nerve?
C5-T1
What is the motor function of the Median nerve?
Thenar muscles
Lateral 2 lumbricals
Flexor muscles of anterior compartment of the armexcept flexor carpi ulnaris and medial half of flexor digitorum profundus which is supplied by the ulnar nerve
What is the sensory function of the Median nerve?
Lateral part of the palm via the palmar cutaneous branch
lateral 3.5 fingers on the anterior side via the digital cutaneous branch.
What are the causes of Carpal tunnel syndrome?
WRIST
W - Water retention - pregnanacy, hypothyroidism
R - Radial fracture
I - Inflammation - RA, Gout
S - Soft tissue swelling - Acromegaly, Amyloidosis, Lipomas
T - Toxic - DM, Alcohol
What are the symptoms of Carpal tunnel syndrome?
Tingling/pain in thumb, index and middle fingers
Pain worse at night or after repetitive movements
Pain relieved by shaking or flicking hand
Clumsiness
What are the signs of Carpal tunnel syndrome?
Decreased sensation over lateral 3.5 fingers
Decreased 2 point touch discrimination - Early sign of irreversible damage
Wasting of the thenar eminance - Late sign of irreversible damage
Positive Phalens test (Inverted prayer - 1 minute - recreates symptoms)
Positive Tinnels test (Tapping over carpal tunnel recreates symptoms)
What investigations can be done for Carpal tunnel syndrome?
Not usually done
Can do nerve conduction studies
Can do USS
What are some of the non surgical managements of Carpal tunnel syndrome?
Treat underlying cause
Wrist splints - maintain neutral position, especially at night
Local steroid injections
What is the surgical management of Carpal tunnel syndrome?
Division of the flexor retinaculum (Carpal tunnel decompression)
What are some of the complications of Carpal tunnel decompression?
Scar formation - High risk of keloid/hypertrophic scarring
Scar tenderness
Failure to relieve symptoms
Nerve injury - Palmar cutaneous branch of Median nerve, Motor branch to thenar muscles
What is Pronator syndrome?
Entrapment of the Median nerve between two heads of pronator teres
What is Anterior interroseous syndrome?
Compression of the anterior interosseous
branch of the Median nerve by the deep head of pronator teres
- NO SENSORY DEFICIT
- Causes muscle weakness of Pronator quadratus, Flexor Pollicis Longus, Radial half of Flexor Digitorum Profundus
