It is important to mention the date of this article which is July, 2015. The reason I bother to state the date is simply because in the world of ankle surgery, particularly that of ankle implants, the technology is changing at a very rapid rate.
If you scan the internet for information on ankle implants (artificial joints), you will get a very diversified opinion as to the long term effectiveness of ankle implants. In spite of the fact that implants have been available for other joints of the body, for a long time, with a good track record, it seems that has not been the case with the ankle joint.
Total ankle arthroplasty has been performed over the last 40 years or so and whenever a new technique or new materials were introduced, there seemed to be an early air of enthusiasm soon to be followed by disappointment.
The higher than normal failure rates for ankle implants can be attributed to the following:
An obese patient is another criteria that will expedite implant failure. For obvious reasons, if a patient is extremely overweight this over stresses the ankle joint and the implant and increases the possibility for implant failure.
Diabetics, simply because of the inherent lower extremity problems a poorly controlled diabetic exhibits, this too can lead to implant failure. Many diabetics simply should not have lower extremity surgery because of poor vascular status and increased chance of infection and the inability to fight infection should one occur.
Osteoporosis, or demineralization of bone. If the bone stock of the ankle and tibia bone are not adequate, at the very least, the implant if more likely to loosen up and then fail.
Abnormal gait patterns in individuals who suffer from neurological disease such as Parkinson's disease or Multiple Sclerosis or other similar disease entities.
Prior to the advent of ankle implants, the only real option in chronic ankle pain was to fuse the ankle joint. Keep in mind that this article is about chronic, severe ankle pain that has not responded to more conservative treatments.
Conservative treatments that should be tried prior to ankle arthroplastic procedures include orthotics, AFO or ankle-foot orthosis which is essentially a combination orthotic and ankle brace, physical therapy, cortisone injections and ankle arthroscopy.
Although ankle fusions generally work out well, there are inherent problems with this procedure. Because the ankle joint is fused, meaning there is no longer any motion within that joint, it tends to put excessive pressure on the adjacent joints, in particular the subtalar joint which is the joint just below the ankle joint.
Since normal gait is predicated on the ability of the ankle to bend, when this motion has been stunted, it has to change the gait pattern in the individual.
The amount of damage that can be done will depend on a number of factors.
It is estimated that roughly ten percent of people who have had an ankle fusion will go on to require a fusion of an adjacent joint.
The attraction to an ankle implant is the hope that the painful degenerated ankle joint can be replaced with an artificial joint which will allow the individual to return to some semblance of a normal life style. This is particularly true of the younger, more active person. Of course, as already stated, there is always the concern about the patient out living his implant and the need for another surgery.
Studies comparing ankle fusions vs. ankle implants have generally found that both groups function similarly when walking on flat surfaces. People who have had ankle implants tended to exhibit better functionality when going up and down stairs and ambulating on uneven surfaces.