13: Nervous System I Pathologies Flashcards
Carpal Tunnel Syndrome
- The median nerve becomes compressed in carpal tunnel syndrome.
- The Carpal Tunnel is a narrow passageway in the anterior wrist that contains tendons and the median nerve.
- This median nerve carries sensory information to the hand and controls movements in the hand and fingers.
Carpal Tunnel Syndrome: Causes
- Fluid retention: pregnancy.
- Overuse –vibrating tools, desk posture.
- Due to: RA, hypothyroidism, acromegaly.
- Trauma (swelling), tumour or fracture in wrist. Small carpal tunnel (congenital).
Carpal Tunnel Syndrome: Signs and Symptoms
- Tingling, numbness orpain in the median nerve distribution.
- Symptoms are often worse at night and can wake patient.
- Weakness of grip and weak thumb opposition.
- Muscle wasting at base of the thumb (sensory symptoms 1st).
Carpal Tunnel Syndrome: Diagnosis
- Tinel’s test & Phalen’s test (+ve if reproduces hand symptoms).
- Nerve conduction studies
Carpal Tunnel Syndrome: Treatment
- Anti-inflammatory drugs, corticosteroid injection, splinting the wrist, physiotherapy.
- Surgery (cutting transverse carpal ligament).
Carpal Tunnel Syndrome: Complications
• In chronic and / or untreated cases, the muscles at the base of the thumb may degenerate.
Bell’s Palsy
The nerve that controls the facial muscles (facial nerve) becomes inflamed or compressed.
Bell’s Palsy: Causes
Viral e.g. Herpes simplex
Surgery
Injury.
Bell’s Palsy: Signs and Symptoms
- Sudden unilateral weakness or paralysis of the facial muscles.
- Cannot close affected eye (can damage cornea).
- Loss of taste & intolerance to loud noise if severe.
Bell’s Palsy: Treatment
Acyclovir
Cortisone
Guillain-Barre Syndrome
- Guillain-Barre is a form of post-infectious de-myelinating disease with ‘neuritis’.
- Associated with acute, ascending, progressive inflammation and demyelination of peripheral nerves.
Guillain-Barre Syndrome: Causes
Auto-immune. 75% are triggered by a recent infection (1-3 weeks after respiratory/GIT infection or post-vaccination e.g. flu / EBV). Antibodies formed against virus cross react with lipids in myelin –molecular mimicry
Guillain-Barre Syndrome: Signs and Symptoms
- Sudden, progressive, bilateral, ascending paralysis.
- Paraesthesia and sensory changes.
- Neuropathic pain into legs.
Guillain-Barre Syndrome: Diagnosis
• Nerve conduction studies, lumbar puncture.
Guillain-Barre Syndrome: Treatment
- Emergency care -respirator, intensive care.
* Plasma exchange, intravenous antibodies, corticosteroids.
Guillain-Barre Syndrome: Complication
Death by heart or respiratory failure.