Trunnionosis, Metallosis, and Their Effects
What is Trunnionosis?
Hip replacements, specifically of the metal-on-metal variety, are composed of several parts, including the ball, the stem, and the prosthesis. In the majority of hip replacements that are produced today, the prosthesis rests on top of the ball. This allows the femoral head to be modular, fitting better into the socket joint of the pelvis. The trunnion is the place where the femoral neck tapers off, attaching to the femoral head.
As previously stated, the trunnion is necessary in order to attach the femoral neck to the femoral head. However, a recent development has alerted doctors to a connection between this style of hip implant, (metal-on-metal), and the presence of foreign, malignant metal debris in and around the area of the implant. The movement of the hip implant creates this debris as it wears against itself and sends shards of metal into the surrounding soft tissue. The wearing away of the metal trunnion is known as “trunnionosis.”
The existence of these eroded metals from the trunnion in the body is highly dangerous and painful for those experiencing their effects, and they have been known to cause many adverse consequences, including, (but not limited to), tissue necrosis.
Trunnionosis is also often referred to as “metallosis,” though in truth, metallosis is more specifically concerned with the problem of the build-up and the presence of metal debris in the body, while “trunnionosis” refers to the overall process of the trunnion wearing and causing the problem of “metalosis.” However, you may often hear physicians, attorneys, and experts use the two terms “trunnionosis” and “metallosis” interchangeably
What does Trunnionosis (Metallosis) cause?
Many, if not all patients who suffer from trunnionosis are at a high risk for many other medical problems. The two metals used most often in metal-on-metal hip implants are Chromium and Cobalt. Negative effects may be experienced by the unintentional presence of both metals in the human body. In addition, Cobalt is highly toxic and poses a serious threat when it migrates into unintended areas of the body.
Specifically, when Chromium and Cobalt invade the vulnerable soft tissue around the hip implant it increases the likelihood that they will be absorbed into the bloodstream, which can lead to many serious issues, including future neurological and cardiac problems. Although the previously mentioned issues may be the most serious, trunnionosis (metallosis) has also been known to cause joint loosening and dislocation, bone chipping and fracturing, and the development of pseudotumors, all of which are serious medical concerns and should be addressed immediately by a doctor.What Should I do if I think I have Trunnionosis or Metalosis?