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Hand & Wrist Exam

Muscle Inspection


Muscle Wasting

    • Look For

    • Decreased mass of the thenar and/or hypothenar eminence.
    • Causes of Localised Wasting

    • 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) - ulnar nerve lesion e.g. entrapment at or above the cubital fossa
    • Causes of Generalised Wasting

    • Normal aging
    • Disuse
    • Malnutrition - poor diet, malabsorption, cancer
    • Denervation - trauma, ALS, Guillain-Barre Syndrome, neuropathy
    • Muscular disorders - inflammatory myopathy, muscular dystrophies
    • 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.

Muscle Spasms

    • Look For

    • Spontaneous, uncontrollable contraction(s) of muscle. Note whether the spasm affects a single region, is generalised or affects the ipsilateral arm and leg.
    • Causes of Muscle Spasms

    • Exercise-induced spasm (cramping)
    • Dehydration
    • Electrolyte abnormalities - hyper/hyponatraemia
    • Hereditary dystonia - idiopathic, Huntington’s, Wilson’s
    • Acquired dystonia - brain damage, encephalitis, parkinsonism, brain tumour, stroke, drug-induced
    • Factitious dystonia


    • Look For

    • Visible, spontaneous localised muscle contraction and relaxation.
    • Causes of Fasciculations

    • Benign / normal
    • Lower motor neuron disorders - ALS, radiculopathy, peripheral neuropathy, entrapment, syringomyelia, Creutzfeldt-Jakob disease
    • Metabolic disorders - thyrotoxicosis, tetanus, anticholinesterase medications
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