Table 1

Clinical findings in eight male cases of Hirayama’s disease

Patient 1Patient 2Patient 3Patient 4Patient 5Patient 6Patient 7Patient 8
Muscle atrophy: hand +; hand and forearm ++; hand, forearm, and arm, +++.
L, left; R, right
Age (years)5968263345232125
Height (cm)175162172185182180170182
Onset age (years)1825171819171718
SymptomsR cold paresis, weaknessL cold paresis, weaknessR weaknessL weakness, cold paresisL cold paresis, weaknessL cold paresis, weaknessL cold paresis, weakness, tremorR weakness, tremor
ProgressionR + L, 1 yearBiphasic: 
 L 25 months, R 42 monthsR and L, 2 yearsBiphasic: 
 L 18 months, 
 R 22 monthsBiphasic: 
 L 19 months, 
 R 22 monthsMonolateralMonolateralMonolateral
AtrophyR+++, L++R++, L+++R++, L+R+, L++R+, L++L+++L++L++
Tendon reflexes
    Upper limbsBriskNormalReduced (R<L)ReducedReducedReduced (L<R)NormalReduced (L<R)
    Lower limbsBriskBriskNormalNormalNormalNormalNormalNormal