A new metal hip replacement lawsuit has joined the existing litigation over DePuy’s Pinnacle hip implant. The metal hip replacement lawsuit echoes similar concerns related to side effects and the safety of the device.

The Pinnacle Hip Replacement System is a type of artificial hip joint. Artificial hip joints are medical implants designed to replace a failing hip joint. Many factors can cause a person’s hip joint to fail, including arthritis, physical injury, and even normal wear-and-tear.

However, the Pinnacle Hip is a specific type of artificial hip. In a healthy human hip, the joint between the upper leg bone and the hip is protected by a lining of cartilage and lubricating fluids. However, artificial hip joints have to take steps to reduce friction where the parts of the implant meet. In many artificial hips, the interfacing surface is comprised of a polymer or ceramic. However, in metal-on-metal hip implants like the Pinnacle system, the metal itself is supposed to be a special alloy that does not need additional protection from grinding. However, this new metal hip replacement lawsuit and others have alleged that metal-on-metal hip implants perform worse than other types of artificial joints.

The metal hip replacement lawsuit was filed by plaintiff Michael Hackett of Michigan. In 2008, Hackett had his right hip replaced with the Pinnacle System at Central Michigan Community Hospital in Mount Pleasant, Mich. However, in 2013, his physicians learned that Hackett had experienced bone degradation, fluid buildup, and soft tissue damage around the device. Early this year, Hackett underwent revision surgery to replace the device. His metal hip replacement lawsuit alleges that the Pinnacle Hip was inherently defective.

Similar metal hip replacement lawsuits have alleged that there are a variety of problems associated with metal-on-metal hip implants, including the Pinnacle Hip. Metal-on-metal hip implants allegedly can slowly grind their metal surfaces against each other, grinding off tiny flakes of metal. In this form, the suits allege, the metal can more easily dissolve into the patient’s body and cause a variety of complications, including tissue damage and tumor-like growths around the implant. The alleged irritation and damage is extremely painful. Additionally, it has been alleged that metal-on-metal hip implants fail more often than other artificial hips, requiring revision surgery. Revision surgery is the process of repairing or replacing a failed hip implant. Revision surgery may be more technically complex that the original hip replacement, as the process of implanting an artificial hip involves removing some of the original bone from the hip. This leaves surgeons with less material to work with during the revision surgery.

Hackett’s metal hip replacement lawsuit has joined existing lawsuits in the form of a multidistrict litigation or MDL. MDLs are a type of group lawsuit, similar in some ways to a class action lawsuit. Both MDLs and class action lawsuits allow a group of patients who have allegedly suffered similar harm at the hands of the same defendant to combine their lawsuits. The main difference is that class action lawsuits start out as group lawsuits, while MDLs consist of a group of individual lawsuits which are later coordinated into a single legal proceeding.

The individual metal hip replacement lawsuit is titled Michael J. Hackett v. DePuy Orthopaedics Inc., et al., Case No. 3:14-cv-00827-K, filed within the MDL In re: DePuy Orthopaedics Inc., Pinnacle Hip Implant Products Liability Litigation, MDL No. 2244, in the U.S. District Court for the Eastern District of Michigan.