Compartment Syndrome: Rare Disorder Tackles Oregon Football Team

(CBS/AP) Three members of a high school football team in Oregon have been diagnosed with compartment syndrome, a rare soft-tissue condition that causes soreness and swelling in their triceps.

The three were among at least 18 players from McMinnville High School who were sickened following a recent practice session.

"To have an epidemic like this is very weird," said Dr. Craig Winkler of Willamette Valley Medical Center in McMinnville.

All of the players had elevated levels of the enzyme creatine kinase, or CK, which is released by muscles when they're injured, he said. High CK levels can lead to kidney failure if not properly treated.

Officials said the cause was still not known, but high CK levels can result from vigorous exercise or the use of certain medications or food supplements.

"It's a mystery," says CBS News medical correspondent Dr. Jennifer Ashton. "There are only ten case reports of upper extremity, of tricep compartment syndrome in the medical literature. It is exceedingly rare."

Five of the athletes were treated in the emergency room and sent home, according to the Associated Press. The others were admitted to the hospital and given intravenous fluids to maintain adequate hydration and prevent kidney failure.

As of Sunday, 10 remained hospitalized, but they were in good condition and were expected to be released Monday, said Rosemari Davis, Willamette Valley Medical Center's chief executive officer.

CBS News' The Early Show has more on the story.