As a physical therapist with many years of experience in the area of tennis injury prevention and rehabilitation, including work with several ATP tour pros, I believe that it is important to determine the possible cause/s of the injury, and take appropriate corrective/preventive measures, to avoid a recurrence of the injury.
In Maria's case, it is my observation that a possible contributing cause to her shoulder injury may be the way she hits her sharp-angled, topspin crosscourt forehand, when she is pulled wide to her right on the deuce side of the court. She uses her right arm primarily to generate both power and topspin, which puts a great deal of stress on her rotator cuff muscles.
How to correct it? - By using the legs, hips, and torso to generate most of the power and spin, and using the right arm primarily for control.
Joseph Zohar, P.T., Irvine, Ca.
KNOWLEDGE IS WASTED - UNLESS IT IS SHARED WITH OTHERS.