Wasting of the Hand Muscles
May 9th, 2019
Overview
Look For
- Decreased mass of the thenar and/or hypothenar eminence.
Interpretation
- Forearm flexor wasting - median nerve lesion, e.g. entrapment at or above the cubital fossa
- Thenar wasting - median nerve lesion, e.g. entrapment at or above the carpal tunnel
- Hypothenar wasting - ulnar nerve lesion e.g. entrapment at or above the cubital fossa
Causes of Muscle Wasting
Localised Muscle Wasting
- Disuse
- Denervation - brachial plexopathy, ulnar or medial nerve lesion, motor neuron disease, Guillain-Barre Syndrome, Charcot-Marie-Tooth
- Muscular disorders - inflammatory myopathy, muscular dystrophies
Generalised Muscle Wasting (Sarcopaenia)
- Frailty
- Malnutrition - poor diet, malabsorption, cancer
- Chronic disease - cancer, heart failure, COPD, infection, cirrhosis, kidney disease
Tip
- Muscle wasting and shiny skin with reddish discolouration is a very specific for reflex sympathetic dystrophy.
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