Carla Muss-Jacobs didn’t give much thought to the tools her surgeon would use to replace her knee. Like most patients, she just wanted to feel better and trusted that any devices in the operating room would be safe.
In her case, the surgeon sliced open her leg and positioned special cutting guides, like carpentry jigs, over her thigh and shin bones to line up his bone saw precisely. The device, called the OtisKnee, was supposed to speed the surgery and the recovery. 
Ms. Muss-Jacobs’s recovery was not speedy. In terrible pain after the operation, she eventually underwent a second knee replacement.
As it turned out, the OtisMed Corporation, the maker of the OtisKnee, did not seek clearance from the Food and Drug Administration for its OtisKnee guides before it started selling them. When the company did apply for F.D.A. review, its application was rejected because, the agency said, the company failed to show that the product was safe and effective.
In December, OtisMed and its former chief executive pleaded guilty in Federal District Court in Newark to criminal charges of distributing adulterated medical devices. The Justice Department said the company sold and distributed 18,000 of its OtisKnee devices from 2006 to 2009 without F.D.A. approval.
No one can say with certainty if the OtisKnee device caused Ms. Muss-Jacobs’s problems, but in announcing an $80 million settlement of criminal and civil charges against OtisMed, United States Attorney Paul J. Fishman said patients “should be entitled to trust that the devices their doctors are using are safe, effective, tested and approved.”
An examination of the OtisKnee case shows how easily that trust can be violated in the rapidly evolving world of medical devices, a thriving $110 billion-a-year industry. If not for a whistle-blower, the public might never have learned about the widespread use of a potentially dangerous device that sidestepped regulation.
About 700,000 knee replacements are performed every year, making it the most common elective surgery in the country. An aging population is increasing demand, creating opportunity for companies that make orthopedic devices and the accessories used to implant them.
OtisMed was an Alameda, Calif., start-up that saw an opening in that growing market. The company’s guides worked with knee replacement components made by other medical device makers. The idea was to use magnetic resonance imaging and three-dimensional software to create guides at an OtisMed facility that were then shipped to the hospitals. The guides directed the angle of the surgeon’s cuts so the artificial knee would be properly aligned. In theory, the method helped surgeons tailor bone cuts to a patient’s anatomy.