Study: Softball pitchers' windmill delivery can cause injury

By Bob Sakamoto | Tribune reporter
April 8, 2009

The cornerstone of girls fast-pitch softball is that the underarm, windmill delivery allows pitchers to undertake outrageous workloads with impunity.

That long-held belief is being refuted by a doctor at Rush University Medical Center in Chicago, and his research could lead to a dramatic re-evaluation of the sport.

"It's the windmill delivery itself that is causing pain to the front of the shoulder," said Dr. Nikhil Verma, a sports medicine specialist. "It stands to reason that excessive use of that motion will lead to this type of injury."

Verma and his research team had their findings published in last month's American Journal of Sports Medicine, and Verma is currently in Osaka, Japan, presenting his research at an international orthopedic sports-medicine forum.

The study found that the windmill delivery puts more stress on the biceps than the overhand delivery used by baseball pitchers.

Lockport senior Dana Bowler was 11-2 last season when she began experiencing shooting pains to the front of her shoulder. It reached a point where she had to shut down her junior season in late April.

"I had just finished a stretch of pitching 21 days in a row with practices, games and warming up in relief," Bowler said. "The last two years was the most I had ever pitched.

"I didn't pitch for two months after that, and it took me another month to get into throwing shape. I'm still not where I was before the injury."

Verma, who was the team physician for the Chicago Bandits professional women's softball team the last three seasons and works with DePaul's softball team, first became aware of the issue when several Bandit pitchers came to him with the same ailment. He said he was able to localize the pain to the biceps tendon.

"One of the Bandit pitchers ruptured her biceps tendon while she was playing," Verma said. "It's not only the windmill motion, but overuse that can cause injury.

"Competitive female pitchers can be asked to pitch every game during a weekend tournament—the equivalent of 12,000 pitches in as little as three days."

Verma said that previous studies have shown anterior shoulder pain being the "common culprit" of shoulder injuries. Four Bandit pitchers and three college pitchers were the subjects of a six-week study at Rush's human-motion laboratory last spring.