Unfortunately, hip replacements can fail for a variety of reasons. Fortunately, revision hip surgery is possible for the great majority of these cases. Total hip revision surgery can range from a simple to a very complex operation. A hip replacement can fail by several mechanisms, fortunately none is common. Infection, dislocation, loosening and fracture around the implant are all causes of failure. Each has a different type of revision surgery that is required.
Revision total hip surgery does have a higher rate of complications compared to primary hip surgery as one would expect. However, revision hip surgery can be very successful and turn a bad situation into a functional and painless hip.
The Possible Causes of Failure in Total Hip Replacement:
1. Infection; Fortunately, infection is rare, occurring in less than 1 percent of cases. The key is avoiding infection in the first place by using sterile technique, efficient surgery, giving antibiotics before and after surgery, etc. If a hip replacement becomes infected, treatment may range from a "washout", to removal of the implant and placement of an antibiotic spacer for 2-3 months, followed by a re-implantation surgery to restore the hip replacement.
2. Dislocation: This is when the ball "pops out" of the socket. If this occurs early, this can normally be put back in the joint, and likely will not happen again. However, if this recurs multiple times, a revision surgery may be needed. Fortunately, this is rare, less than 1 percent of cases.
3. Loosening: The number one cause of long term failure of total hip replacement is a process called osteolysis, which simply means bone destruction. All hip replacements wear. With traditional metal on plastic bearings, this creates microscopic wear particles. If enough wear occurs and too many particles are created, the body's white blood cells can engulf these particles and set off an enzymatic reaction that can destroy the bone around the hip implants, causing them to become loose. Loose implants are painful, leading to revision surgery. Osteolysis, if it occurs, is a late phenomenon of joint replacement. This problem has led to the search for bearing surfaces with reduced wear, such as crosslinked plastic, ceramic on ceramic, and metal on metal. (See Hot Topics for more info)
4. Fracture: Trauma to the operative leg can in rare cases lead to a fracture around the femoral component or stem. If this occurs, depending on the type of fracture and stability of the stem, a revision surgery most likely would be necessary.
Fortunately, all these complications are uncommon. The majority of patients who undergo hip replacement surgery do not have any complication and have a successful outcome.
