My son is 6 years old and we have recently noticed a new spasm in his arm/ arms.He bends at the elbow and does one to three pumps towards his chest.Mostly with the right arm, but sometimes both. He is the youngest of three. He just finished Kindegarten and did wonderfully. He also had both arms/hands in a cast this year. In his left he broke both bones in the forearm at school and was in a cast for 7 weeks. No surgery. He also broke his right hand wresting with his brother and was in a cast for 4 weeks. This is a very new thing we have noticed and are wondering if it could be related to the breaks or casts or if we should be on the watch for something else.