Water polo is an upper extremity sport. Players swim continuously in rapid sprints up and down the pool, changing directions every time the ball changes teams, much like in basketball or soccer. Although the arms are clearly overhead for shooting the ball, they are also kept out of the water while the player is defending the goal (Figure 1).

Water polo is also a contact sport: There is considerable pushing, pulling, and, at times, punching (illegal, of course) during the course of play. Players wear thick, double swimsuits, tied on very tightly, as protection from kicking and scratching, and against opponents holding on and pulling on the suit. Consequently, there are a myriad of injuries that occur to the upper extremities, from the overuse syndrome of swimming to traumatic injuries resulting from wrestling.