Quantitative ultrasound of denervated hand muscles.
BACKGROUND
Presentations to the neuromuscular clinic commonly involve hand muscle denervation, but few studies have evaluated hand muscle ultrasound.


METHODS
Ultrasound studies of abductor pollicis brevis, first dorsal interosseous, and abductor digit minimi were prospectively performed in a cohort of 34 patients (77 muscles) with electromyography (EMG)-confirmed denervation, compared with 58 healthy control subjects.


RESULTS
In control subjects, muscle thickness was highly reproducible [intraclass correlation coefficient (ICC) = 0.88-0.98], and echogenicity was moderately reproducible (ICC = 0.542-0.686). Age, gender, and body mass index influenced muscle thickness and echogenicity. Ultrasound changes in denervated muscles correlated with the severity of EMG abnormalities. A z-score cutoff of 0 identified denervated muscles with a sensitivity of 100% and 89% for echogenicity and muscle thickness, respectively.


CONCLUSIONS
Hand muscle ultrasound provides a noninvasive method to quantify muscle denervation and may be useful as a screening tool before EMG studies.
Department of Neurology, University of California, San Francisco, San Francisco, California, USA.|Neuroscience Research Australia, PO Box 1165, Randwick NSW 2031, Australia.|Prince of Wales Clinical School, University of New South Wales, Australia.
Neil G
NG
Simon
Department of Neurology, University of California, San Francisco, San Francisco, California, USA.
Jeffrey W
JW
Ralph
Department of Neurology, University of California, San Francisco, San Francisco, California, USA.
Catherine
C
Lomen-Hoerth
Department of Neurology, University of California, San Francisco, San Francisco, California, USA.
Ann N
AN
Poncelet
Neuroscience Research Australia, PO Box 1165, Randwick NSW 2031, Australia.|Westmead Clinical School, C24 Westmead Hospital, The University of Sydney, NSW 2006, Australia.
Steve
S
Vucic
Brain and Mind Research Institute, The University of Sydney, Mallett St, Camperdown, Australia.
Matthew C
MC
Kiernan
Department of Neurological Surgery, Northwestern Feinberg School of Medicine, Chicago, Illinois, USA.
Michel
M
Kliot
D000328:Adult; D015331:Cohort Studies; D004576:Electromyography / Q000379:methods / Q000639:trends; D006225:Hand / Q000000981:diagnostic imaging* / Q000294:innervation*; D006801:Humans; D008875:Middle Aged; D009121:Muscle Denervation / Q000639:trends; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging* / Q000294:innervation*; D011446:Prospective Studies; D014463:Ultrasonography
amyotrophic lateral sclerosis; denervation; muscle; nerve injury; ultrasound