The looseness is frequently a results of repetitive overhead motion when swimming and enjoying tennis, such as.  A shoulder dislocation occurs when the head from the humerus (upper arm bone) is forced out in the socket in the shoulder blade. This will transpire from the immediate blow into the shoulder, https://www.theorthopaedicandpainpractice.com/what-are-shoulder-joint-dislocations/?_gl=1*164kc8h*_up*MQ..&gclid=Cj0KCQjwkt6aBhDKARIsAAyeLJ2krYJSOuy5mZksrNqH-VDjQwW1ScD49yD8BUWysDG6u6bJPCSbXVUaAuCPEALw_wcB