Nerve ultrasound in clinical management of carpal tunnel syndrome in mucopolysaccharidosis.
OBJECTIVE
Mucopolysaccharidoses (MPS) are a group of diseases with an almost 100% lifetime incidence of carpal tunnel syndrome (CTS) in MPSsubtypes I, II, and VI. We compared nerve ultrasound with clinical signs and electrophysiology in a clinical setting to screen for CTSin MPS.


METHODS
Twenty-four patients (13 male, 11 female, mean age of 7y 11mo [SD8y 5mo], range 6mo-29y) were screened for CTS. Eight of these patients were re-examined post-operatively. Clinical signs, distal motor latency, compound muscle action potential, sensory nerve action potential amplitude and velocity, as well as echogenicity and the cross-sectional area (CSA) of the median nerve at the wrist and forearm determined with ultrasound were assessed and the wrist to forearm ratio (WFR) calculated. Eighteen healthy participants formed a comparison group, who were also investigated with nerve ultrasound.


RESULTS
In 26% of the patients' hands, clinical signs of CTSwere present; 77% fulfilled electrophysiological and 92% nerve ultrasound criteria for CTS. Post-operatively, electrophysiology improved significantly, whereas ultrasound results were unchanged. In the comparison group, age and height correlated with the CSA, but not with WFR.


CONCLUSIONS
Nerve ultrasound is a useful and painless primary screening tool for CTSin MPS.
Department of Paediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Lübeck, Germany. tobias.baeumer@neuro.uni-luebeck.de.|Department of Neurology, University Medical Hospital Hamburg-Eppendorf, Hamburg, Germany. tobias.baeumer@neuro.uni-luebeck.de.
Tobias
T
Bäumer
Department of Paediatrics, University Medical Hospital Hamburg-Eppendorf, Hamburg, Germany.
Nina
N
Bühring
Department of Neurology, Städtisches Klinikum Dessau, Dessau Rosslau, Germany.
Thomas
T
Schelle
Department of Paediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Lübeck, Germany.
Alexander
A
Münchau
Department of Paediatrics, University Medical Hospital Hamburg-Eppendorf, Hamburg, Germany.
Nicole
N
Muschol
D000293:Adolescent; D000328:Adult; D002349:Carpal Tunnel Syndrome / Q000000981:diagnostic imaging* / Q000209:etiology / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008475:Median Nerve / Q000000981:diagnostic imaging*; D009083:Mucopolysaccharidoses / Q000150:complications*; D009431:Neural Conduction / Q000502:physiology; D014463:Ultrasonography / Q000379:methods / Q000592:standards*; D055815:Young Adult