The symmetry indexJH was 6.3 ± 4.8 %, and it was over 11.1% (mean + 1 SDs) in 6 subjects, from 8.5 to 11.0% (mean + 0.5 SDs) in 5 subjects, from 1.5 to 3.9% (mean - 0.5 SDs) in 6 subjects, under 1.5% (mean - 1 SDs) in 5 subjects, and from 4.0 to 5.9% in the remainder (n = 5).