Patients Sue B. Braun alleging defect in Aesculap replacement knees

Medical device maker B. Braun concealed from regulators problems with its line of ceramic-coated artificial knees and promoted the products to surgeons despite knowing some of their Aesculap knee replacement devices were prone to fail, a lawsuit filed in a California court alleges.

The Bethlehem-based company’s Aesculap Implant Systems subsidiary marketed the “advanced surface” ceramic coated knees as superior to standard bare metal implants, claiming they would last longer, the lawsuit says. But the ceramic joints were defective, the suit alleges, because they didn’t adhere properly to cement used to bond them with the patients’ bones.

As a result, the 25 knee replacement patients who are suing B. Braun and Aesculap in a California court were or will be required to undergo additional surgeries to correct problems with the joints or implant different devices, the suit says.

A spokesman for B. Braun, a German company with U.S. headquarters in Bethlehem, did not respond to messages Tuesday.

The lawsuit was filed last month in Los Angeles Superior Court by attorneys Christopher K. Johnston of Guaynabo, Puerto Rico, and Anthony Buzbee of Houston on behalf of the patients, who are from Louisiana, Florida and 10 other states.

According to the Aesculap knee replacement lawsuit, Aesculap sought and received permission from the U.S. Food and Drug Administration to sell its advanced surface replacement knees by demonstrating that the devices were as safe and effective as devices that had already been approved. The process is less rigorous than the FDA’s standard medical device approval process, the suit says.

The lawsuit alleges that the advanced surface joints’ ceramic coating caused moisture to collect between the implants and the bone cement used to connect them to patients’ femurs or tibias. As a result, the suit alleges, the implants loosened and failed prematurely.

It is common for doctors who are removing a replacement knee implant to use a saw to cut through the bone cement, the suit says. In cases involving Aesculap’s ceramic coated joints, surgeons found “the implant components were easily removed by hand, using just two fingers, or after a single mallet strike,” the suit alleges.

B. Braun and Aesculap were told by physicians on numerous occasions that joints that had been removed had no cement attached, the suit claims. The companies responded by blaming the failures on the brand of bone cement, the use of cement containing antibiotics or the addition of antibiotics or the surgeons’ cementing technique, the suit alleges. They did not, however, include with the implants specific instructions regarding the type of cement to be used or the technique to be used, the suit alleges.

The suit claims B. Braun and Aesculap concealed the scope of the problem from doctors, sales people and the FDA. It also alleges the companies failed to properly test the devices before putting them on the market. The suit alleges that they prematurely ended a clinical trial after one of the participating physicians noticed the bond between the implant and cement had failed.

“Defendants terminated the study in bad faith to intentionally conceal the true risks and dangers associated with the ceramic coating,” the suit alleges.

The suit also claims the companies failed to report the failures to the FDA.

By Peter Hall