The five companies that provide nearly all the replacement hips and knees used in America have agreed to pay $310 million and accept federal monitors to settle concerns over doctor kickbacks following a sweeping Justice Department investigation.

From at least 2002 through 2006, the companies paid orthopedic surgeons “exorbitant” amounts to be consultants and use their products exclusively, said Christopher J. Christie, the U.S. Attorney for New Jersey. Patients and hospitals were unaware of the deals, which ranged from tens to hundreds of thousands of dollars a year and included trips.