(HealthDay)—Disc herniations represent a substantial source of injury in the National Football League (NFL), according to a study published in the Oct. 15 issue of Spine.

Benjamin L. Gray, M.D., from Washington University in St. Louis, and colleagues conducted a retrospective analysis using data from the NFL's Sports Injury Monitoring System to determine the incidence, location, and type of disc herniations among . All disc herniations to the cervical, thoracic, and lumbar spine during a 12-season period (2000 to 2012) were included in analyses.

The researchers identified 275 disc herniations that occurred in the spine, 76 percent of which occurred in the lumbar spine, most frequently affecting the L5 to S1 disc. Offensive linemen were injured most frequently, with blocking activity causing most injuries. The prevalence of lumbar disc herniations increased, and the associated mean loss of playing time was more than half the season (11 games). Thoracic disc herniations resulted in the largest mean number of days lost overall, while the most practices were missed by players with cervical disc herniations.

"Disc herniations represent a significant cause of morbidity in the NFL," the authors write. "Although much attention is placed on , preventive measures targeting the cervical, thoracic, and lumbar spine may help to reduce the overall incidence of these debilitating injuries."

Relevant financial activities outside the submitted work were disclosed.