WEDNESDAY, March 26 (HealthDay News) -- The height of a
pitcher's mound can influence the risk of stress-related elbow and
shoulder injuries, suggests a study led by the head team physician
for the Milwaukee Brewers.
The study included 20 pitchers from Major League Baseball
organizations and Milwaukee-area NCAA Division I-A college
teams.
"Our researchers employed a motion analysis system using eight
digital cameras that recorded the three-dimensional positions of 43
reflective markers placed on the athletes' bodies," study leader
Dr. William Raasch, an associate professor of orthopedic surgery at
the Medical College of Wisconsin in Milwaukee, said in a prepared
statement. "Then we analyzed the pitching motion at mound heights
of the regulation 10 inches, along with eight-inch and six-inch
mounds, as well as having the athletes throw from flat ground."
The researchers examined pitching motion position and velocity,
along with the forces and torques generated at the shoulder and
elbow.
"We found that compared to flat ground, pitchers using a 10-inch
mound experience an increase in superior shear and adduction torque
in the shoulder -- meaning there's a greater amount of stress on
the joint surface and surrounding structures," Raasch said.
"That greater stress may result in injury to the shoulder
including tearing of the rotator cuff or labrum, which may result
in surgery and long-term rehabilitation. It also can make it
difficult for the athlete to replicate the same throw and develop a
consistent strike," he said.
He and his colleagues found that the "most notable kinematic
difference was the increase in shoulder external rotation at foot
contact. This probably represents a change in the timing of the
foot contact relative to arm position, because the foot lands
earlier in the pitch delivery during flat ground throwing than with
a slope."
This study didn't provide enough data to make a recommendation
on whether the standard 10-inch mound height should be changed, but
the findings do offer trainers information that may help them
determine if pitchers should practice on flat ground, especially
after an injury, Raasch said.
The study, funded by Major League Baseball (MLB), was presented
at a joint session of the Major League Baseball Team Physicians
Association and Professional Baseball Athletic Trainers Society,
held at the MLB winter meetings.
More information
The American Academy of Orthopaedic Surgeons has more about
throwing-related injuries in the elbow.
