Controversial Surgeon’s Dismissal

Producer of joint replacement devices, Zimmer Inc. is surrounded by controversy regarding the device quality and safety of their NexGen CR-Flex cementless total knee replacement implant. There is also controversy regarding how it parted ways with one of its top consultants, Dr. Richard A. Berger, after complaints of Zimmer knee failure.


Dr. Berger is currently an assistant professor and orthopedic surgeon at Rush University Medical Center in Chicago, IL. He began his college career with an undergraduate degree in mechanical engineering from MIT, and graduated in 1985. He then attended medical school at Tufts University School of Medicine in Boston, MA. After graduating in 1989 he went on to perform his residency in orthopedic surgery at the University of Pittsburg in Pittsburg, PA. In 1995 when he completed his residency program he accepted a fellowship opportunity in joint replacement at Rush University Medical Center where he appears to have stayed.

Berger has accredited his degree in mechanical engineering from MIT in helping him design specialized instruments, which allow him to perform surgery without cutting any muscle, tendon or ligament, as well as design gender-specific implants that fit and perform better for active patients. For Zimmer Inc., Dr. Berger worked as a paid consultant for more than a decade. He was considered by them as a specialist, and was involved in their surgical implant designs and techniques. His disagreement with the company began with the NexGen CR-Flex device which was designed to last 15 years. However, he noticed that there was a failure pattern occurring in patients only one year post-operatively. When Berger initially brought his concerns to company officials they responded by pointing to NexGen’s successful usage rate. The next time he voiced his concerns to Zimmer, the company maintained that the problem was not from their device, but rather from Berger’s surgical technique.

Berger said he had hoped to avoid a public showdown with the company so he followed a more traditional route and performed a study with another Rush University surgeon, Dr. Della Valle, who also had issues with the Zimmer knee failure rate. Their relationship finally ended abruptly after Berger participated in a paper presented at the 2010 Annual Meeting of the American Academy of Orthopedic Surgeons regarding the failure rate. Soon after the study was made public, Zimmer cut Berger from its consultant payroll. Zimmer, however, claims that the termination was part of a normal rotation of consultants.