Joint Fusion Vs. Joint Replacement Surgery
Over the past 25 years, joint replacement surgery has become an increasingly common procedure. However, not all affected joints are candidates for replacement. Joint fusion or arthrodesis, can be the better consideration for:
The ends of two bones are fused together in arthrodesis with screw fixation and possible bone grafting. Reasons for considering a joint fusion include:
- affected joint has become unstable
- joint damage has occured from injury or disease
- joint pain occurs when moved
The goal of arthrodesis is pain relief and regained stability and strength. The bones are aligned in the most functional position, but lose their natural motion.
In 1996, I (Carol Eustice, Arthritis Guide for About.com) had right ankle fusion surgery. In 1998, I had my left ankle fused. After living with rheumatoid arthritis for over 29 years, and having the experience of both joint replacement surgery and fusion, I have developed my own perspective. Recently, a series of questions were asked of me and I offered the following answers:
Question: What makes ankle fusion preferable over total ankle replacement?
Answer: In theory, ankle replacement should be preferable over ankle fusion since motion would be preserved. Relief from pain and regained stability are attainable results from fusion. In 1997, doctors in Pittsburgh announced a new total ankle replacement system. Since then, ankle replacement systems have improved, but there still is concern over long-term failure rates.
Question: Is radiographically visible joint destruction necessary before a fusion is done? At what stage in the progression of arthritis is it best to have a fusion done? Is it necessary to wait for much destruction to occur?
Answer: Yes. Fusion is done as a last resort after medications and pain treatment plans produce unsatisfactory results. The extreme pain which justifies fusion surgery is felt when bone rubs on bone after cartilage has significantly worn away. There would certainly be x-ray evidence of such destruction.
Question: Does the fusion really alleviate all the pain?
Answer: Speaking from personal experience, yes, it does alleviate all the pain. The best result is derived from surgery without any complications and from expert technique by the surgical team. Failure to place the ankle in the "optimal position" can lead to a poor clinical result.
Question: How much motion is sacrificed for pain relief?
Answer: Essentially all. The joint is placed in a fixed position. If the ankle is fused in the optimal position, some compensatory increase in motion can be expected at the midtarsal joints. Rocker bottom shoes are usually recommended to compensate for loss of motion but I personally never felt the need for them.
Question: How long does the patient have to be non-weightbearing after an ankle fusion?
Answer: For the first 6 weeks the patient is non-weightbearing. Unprotected weightbearing can begin only after some bone striation is visible on x-ray at the site of fusion.
Question: After the pins are removed how long do you have to be in a cast?
Answer: The average immobilization time until all casts are removed is between 4 and 7 months. The pins are not removed if the internal fixation operative technique is used. There also are external fixation techniques as well as arthroscopic arthrodesis.