Implant Loosening and Revision Surgery
Revision surgery partly or fully renews an implant that has loosened, worn or become infected over time. Accurate diagnosis and careful planning shape the result.
Knee and hip implants work well for many years in most patients. Over time, however, an implant can separate from the bone, its parts can wear, or an infection can develop. In these cases, the implant may need to be partly or fully renewed. This is called revision surgery.
Why does an implant loosen?
- Wear: Microscopic particles from the plastic insert between the joint surfaces can cause the surrounding bone to break down.
- Mechanical loosening: Years of loading can weaken the bond between implant and bone.
- Infection: Bacteria settling around the implant can cause loosening and pain. It can appear early or years later.
- Fracture around the implant: A fall can break the bone around the implant.
- Recurrent dislocation or instability: Especially in hip replacements, poor soft tissue balance can lead to dislocation.
What are the signs?
New pain in a joint replacement that used to be comfortable is the most important warning sign. The pain often increases with weight bearing, standing up or the first steps. A feeling of looseness, swelling, warmth, a change in walking or a shorter leg may also appear. Fever or discharge from the wound suggests infection and should be checked without delay.
How is it diagnosed?
Serial X-rays show changes between the implant and the bone. CT, a bone scan and blood tests are requested when needed. If infection is suspected, testing fluid taken from the joint is an important part of diagnosis. Finding the exact cause of loosening determines the treatment.
How is revision surgery done?
Revision surgery is more extensive than the first replacement and needs careful planning. Loose parts are removed, bone loss is filled with bone grafts or special augments, and revision implants with longer stems and stronger fixation are fitted. Sometimes replacing only the worn plastic insert is enough.
When there is infection, treatment is usually done in two stages: the implant is removed and replaced with a temporary antibiotic-loaded spacer, and a new implant is fitted once the infection is under control. In suitable cases, a single-stage exchange is possible.
Recovery
Recovery after revision can take somewhat longer than after the first replacement. How much weight you can put on the leg depends on the degree of bone loss and the technique used. The physiotherapy programme is individual, and follow-up visits are more frequent.
Preparing for revision surgery
Before revision, general health is assessed in detail. Reports from the previous operation and details of the implant are obtained where possible; they help plan which parts will be replaced and which instruments to prepare. A new implant is not fitted until infection has been fully ruled out.
Frequently asked questions
My replacement hurts. Do I definitely need a revision?
No. Pain in a joint replacement is not always caused by loosening; soft tissue problems, back-related pain or tendon inflammation can cause similar symptoms. Revision is not decided before an accurate diagnosis.
How long does revision surgery take?
It depends on how many parts are replaced and how much bone has been lost. It usually takes longer than the first replacement.
If there is an infection, is the implant replaced immediately?
Some infections caught early can be treated by cleaning the joint and giving antibiotics while leaving the implant in place. Established infections usually require a two-stage exchange.
How long does a revision implant last?
Revision implants can also work for many years. The result depends on the amount of bone loss, whether there was infection and the patient's general health.
The information on this page is general and does not replace an examination. An examination is needed to decide which treatment suits you.