The high incidence of anterior shoulder pain in female softball pitchers appears to be the result of the "windmill" pitching motion, say U.S. researchers who studied seven players.
"The conventional belief has been that the underhand throwing motion of softball places little stress on the arm. But that is not the case," lead author Dr. Nikhil Verma, of the Rush University Medical Center in Chicago, said in a Rush news release, United Press International reported.
The researchers found that muscle force used during the softball windmill pitch is much higher than the upper arm pitch used in baseball. The study also found that the biceps, not the elbow, take the majority of stress in the windmill pitch.
The study was published in The American Journal of Sports Medicine.