Revision Knee Replacement
Although the failure rate is low, knee replacements do not last forever. There are two main reasons to revise a knee replacement with the most common being infection, which can cause early loosening of the knee replacement. This usually occurs in the first couple of years after the initial operation and is often due to an infection at the time of the initial surgery.
The other main reason for failure is the loosening of the knee replacement. This generally occurs several years after initial operation and can be due to a mechanical failure of the knee replacement. In some early knee replacement designs, the plastic part of the tibial component became worn and fragmented after approximately eight to ten years. Newer designs have considerably better durability but, eventually, even these will show signs of wear.
The surgery involves removing the old knee replacement whilst leaving as much of the original bone as possible. There can be a considerable amount of bone loss, particularly if the old knee replacement has been infected. If this is the case, it may be necessary to complete the procedure with two operations. In the first, the old knee replacement is removed and the wound is closed. Then antibiotics are given and the infection eradicated over 4-6 weeks. The second stage involves the insertion of the new knee replacement. This technique minimises the risk of any further infection.
Revision knee replacement recovery takes longer than a standard total knee replacement and has a slightly higher complication rate. The prosthesis may also not last as long as a primary knee replacement. Surgery is usually performed through the same incision but may need some extension. The risks and complications are similar to standard knee replacement surgery.