A medical device company near Philadelphia has pleaded guilty to criminal behavior for conducting unauthorized tests of its bone cement on spinal surgery patients.

Synthes Inc. and its Norian subsidiary tested the cement from 2002 to 2004 on 200 patients, three of whom died on the operating table.

Prosecutors say the companies sought profits over patient safety.

Four Synthes executives could get jail time after pleading guilty to a federal misdemeanor.

Norian pleaded guilty Tuesday to conspiracy to impede federal safety standards, a felony, and 110 related misdemeanors. Synthes pleaded guilty to the same misdemeanor, shipping a mislabeled product.

The West Chester-based companies will pay $23 million in fines.

A lawyer for Synthes declined to comment.