A new study published online in the journal Radiology reveals that teenage baseball pitchers who throw more than 100 pitches per week are at risk for permanent shoulder injury. These young pitchers are specifically at risk for a newly identified overuse injury that can impede normal shoulder development and lead to additional problems, including rotator cuff tears, as indicated on a Radiological Society of North America news release. The injury, termed acromial apophysiolysis by the research team, is characterized by incomplete fusion and tenderness at the acromion.

To investigate this pain, Johannes B. Roedl, MD, and a team of researchers conducted a retrospective study of 2,372 consecutive patients between the ages of 15 and 25 years who underwent MRI for shoulder pain between 1998 and 2012, as indicated on the Radiological Society news release. The majority of the patients, who were both male and female, were baseball pitchers. A total of 61 of the patients had pain at the top of the shoulder and an incomplete fusion of the acromion but no other findings, as noted on the Radiological Society news release.

Pitching history was available for 106 of the 122 patients in the study, and through statistical analysis, the researchers found that throwing more than 100 pitches per week was a substantial risk factor for developing acromial apophysiolysis. The Radiological Society news release indicates that among the patients with this overuse injury, 40% threw more than 100 pitches per week as compared to 8% in the control group.

Roedl explains, “The occurrence of acromial apophysiolysis before the age of 25 was a significant risk factor for bone fusion failure at the acromion and rotator cuff tears after age 25.” The severity of the rotator cuff tears was also notably higher in the overuse injury group compared to the control group. Roedl adds, “This overuse injury can lead to potentially long-term, irreversible consequences including rotator cuff tears later in life.”

Roedl and his colleagues suggest teenage and young adult pitchers limit the number of pitches thrown in a week to 100. Roedl says, “Pitching places incredible stress on the shoulder. It’s important to keep training in the moderate range and not to overdo it.”

Source: Radiological Society of North America