Shoulder and elbow kinematics during the Mallet score in obstetrical brachial plexus palsy

•Development of a kinematic protocol based on Mallet score tasks for obstetrical brachial plexus palsy children.•Application of this kinematic protocol to assess shoulder and elbow motion dysfunction in these patients.•This kinematic protocol appeared as a valuable adjunct to clinical scales in management of such patients.•Increased scapulothoracic protraction and posterior tilt in the involved limb during the hand to mouth task.•Decreased glenohumeral elevation excursion in the involved limb during the hand to neck and elevation tasks.