240 patients out of 752 seen over a period of 21 years with traction lesions of the brachial plexus including a palsy of the intrinsic muscles of the hand have been studied by the authors. This study is biased by a high number of imprecisions. Nevertheless it shows that the fate of the intrinsic muscles depends essentially on the initial severity of injury whatever the type of conservative or operative treatment. There is no useful recovery when the lesions of these pathways are more severe than the 2nd degree of Sunderland. Palliative surgery is indicated in cases when all muscles of the forearm have reached a good function after conservative or operative treatment. Reconstructive surgery is however limited or prone to fail in 2/3 of cases because in the vast majority of patients with traction lesions of the brachial plexus there is no recovery of wrist and long finger extensors.