A total knee replacement is expected to last around 15-20 years.* At times, unfortunately, there is a failure of the prosthetic knee to function properly either immediately following the surgery or much sooner than the 15-20 year time frame.* There are a variety of reasons why a prosthetic knee joint may fail early. If you have experienced any of the following difficulties after a total knee replacement, then you may require a revision total knee replacement.*
- Mechanical loosening: The artificial joint begins to separate from the bone. This usually occurs in patients who had a total knee replacement at an earlier age and are now older, but can also occur closer to the time of surgery when the prosthetic is not fit properly to the anatomy of the patient.
- Infection: An infected joint will become stiff and painful, and can potentially loosen as well.
- Bone fractures: If the bone fractures near the artificial joint either from trauma or biomechanical stress, it may be necessary to replace the original prosthesis with a new one with longer stems that will fix the fractures like a metal pin.*
- Instability: Partial or complete dislocation of the artificial joint can cause unsteadiness, limited range of motion, and intense pain. Rapid swelling may occur that can sometimes involve blood and/or other fluid accumulation around the joint.
- Wear and breakage: Over time, parts of the artificial joint may simply wear out and even break, requiring that either part or all of the implant be replaced.* This is more likely in patients who engage in high-impact activities.*
During revision total knee replacement, the original prosthesis is removed and replaced with a new one. This procedure is more complex than a primary total knee revision and requires specialized tools and a skilled surgeon. For these reasons, it is critical that you select a surgeon who has extensive experience performing revision total knee replacements. Dr. Brandon Gough is a talented orthopedic surgeon at Novocur in the Phoenix Arizona area.
A revision total knee replacement typically occurs in two distinct phases:
- First, the surgeon will need to remove the existing prosthetic joint. Because the old implant has likely fused to the bones, some bone may also need to be removed as well.
- A new artificial joint made of either cobalt chrome or titanium is then cemented into place with the addition of stems for added stability of the already weakened bone.
- In some cases, a bone graft is required, moving bone from a donor site on the patient’s own body or more commonly using donated bone. This helps to create more bone surface for the new prosthesis to adhere.
- A specialized prosthetic implant that has been tailored to match the bone structure of each individual patient is required. This prosthetic may also be longer to accommodate the loss of original bone structure.
- Significant pre-operative planning and preparation prior to surgery ensures the new prosthesis accurately and precisely fits into the natural structure of the leg. This is accomplished via pre-operative CT scan, specialized tools to customize the prosthetic implant, as well as advanced technical skill on the part of the surgeon.
Recovery from a revision total knee is similar to recovery from a primary total knee.* A hospital stay of several days is usually required, although most patients are encouraged to stand and walk as quickly as possible, even within hours of the procedure, to facilitate the process of bonding the new implant, growing new bone and to lessen the likelihood of blood clot formation. Physical therapy is recommended for several weeks after the procedure. Within several months, most patients are able to resume normal, low-impact activities.* It is important to note that a revision total knee implant is likely to last around 15-20 years, or longer, if appropriately taken care of, however is not meant to function like that of a primary implant.*
*Individual results may vary.