The influence of handedness on the distribution of muscular weakness of the arm in facioscapulohumeral muscular dystrophy.
The strength of 10 muscle groups in both arms was measured using hand-held myometry to determine the influence of handedness on left-right differences of muscle strength in facioscapulohumeral muscular dystrophy (FSHD). Two groups of subjects were studied: 24 healthy volunteers (19 right-handed), and 53 patients (42 right-handed) with autosomal dominant FSHD. An opposite left-right difference of strength of shoulder and arm muscles was found: right-handed volunteers were stronger on the right side, right-handed patients were stronger on the left side. This opposite left-right difference was statistically significant for the supraspinatus muscle, the wrist extensors and the shoulder internal rotators. The number of left-handed subjects was too small for statistical analysis. The relation between handedness and increased muscle weakness in right-handed FSHD patients suggests that mechanical factors may play a distinct role in the progression of muscle weakness in FSHD.
Brouwer
O F
OF
Department of Neurology, University of Leiden, The Netherlands.
Padberg
G W
GW
van der Ploeg
R J
RJ
Ruys
C J
CJ
Brand
R
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000503:physiopathology*; D009136:Muscular Dystrophies / Q000503:physiopathology*