hi doctor, my son is 5 months old, he was born with erb palsy in right hand due to shoulder dystocia ...He had improved a lot in these 5 months. He now often touches his face, ocationally raises his hand. We are doing his massage and excercises, daily several times as suggested by doctors.but from past few days i m fiding his one hand shorter than another. Pls suggest is this condition permanent any treatment. Pls advice.