Applications of electromyography in the throwing shoulder.

In the complex movement that makes up the baseball pitch, shoulder motion is a single link in an orderly chain of events. It can be argued, though, that herein lies the weakest link and by far the most commonly affected cog in the spectrum of overuse injuries in pitchers. Just why the shoulder receives the brunt of the stress has been the subject of numerous studies in the past several years. The tools of choice in many of these articles have been electromyography and high speed photography which have enabled researchers to study dynamically the phases of the pitch and the sequential firing of the muscles involved. With this information and the knowledge gained from studies looking at muscle activity during specific exercises, the clinician should be able to tailor a rehabilitation program that meets the needs of his or her patient. What has been learned from these articles as applied to the biomechanics of the pitch and the rehabilitation of the athlete who throws and the limitations of this form of study need to be clarified.