Carpal Tunnel Syndrome and other Peripheral Mononeuropathies Flashcards
What is carpal tunnel syndrome?
Compression/entrapment of the median nerve in the carpal tunnel
Aetiology of carpal tunnel syndrome
Idiopathic
Pregnancy
Oedema e.g. heart failure
Lunate fracture
Rheumatoid arthritis
Clinical features of carpal tunnel syndrome
Tingling/pain in first three digits
Worse at night
Relieved by shaking/hanging out hand at night
Clumsiness in hand movements
May be decreased sensation
Unusually symptoms may ascend proximally
Investigations in carpal tunnel syndrome
Nerve conduction studies
Exam findings in carpal tunnel syndrome
Weakness of thumb abduction (abductor pollicis brevis)
Wasting of thenar eminence (NOT hypothenar)
Tinel’s sign (tapping causes paraesthesia)
Phalen’s sign: flexion of wrist causes symptoms
Management of carpal tunnel syndrome
Corticosteroid injection
Wrist splints at night
Surgical decompression (flexor retinaculum division)
What is meralgia parasethetica?
Syndrome caused by compression/entrapment of the lateral cutaneous nerve of the thigh underneath the inguinal ligament
Risk factors for meralgia parasethetica
Obesity
Pregnancy
Tense ascites
Trauma
Surgery
Sports e.g. gymnastics, football, bodybuilding and strenuous exercise
Clinical features of meralgia paraesthetica
Burning, tingling, coldness or shooting pains along outer aspect of upper leg
Deep muscle ache
Symptoms aggravated by standing, and relieved by sitting
Symptoms can be mild and resolve spontaneously or may severely restrict patient
Investigations in meralgia paraesthetica
Diagnosis is clinical
Pelvic compression tests
Injection of nerve with local anaesthetic will abolish the pain
Nerve conduction studies may be useful
Management of meralgia paraesthetica
In most patients condition is self-limited and benign
Weight loss and loose-fitting underwear may help
Uncommonly, local steroid injections may be used in refractory cases
Management of acute multiple mononeuropathy
Urgent assessment
Prompt treatment with steroids
Cyclophosphamide
