RESULTS
Strength Values: Between-side Differences within Groups
In children with BPP, muscles in the impaired shoulder showed significantly less strength than muscles in the unaffected shoulder in all directions (Table 3). Extension and external rotation were the weakest directions, showing a mean between-side difference [(impaired shoulder − unaffected shoulder) over unaffected shoulder] of −76.5% (P=0.001) and −72.2% (P=0.001), respectively. Flexion and abduction were the strongest directions, showing differences of −30.8% (P=0.009) and −34.5% (P=0.001), respectively.