Part 2 – Disadvantages of Osseointegration

Part 2 Disadvantages of Osseointegration

This is the second installment of our four-part series on Osseointegration, Bionic Solutions, and Clinical Outcomes, with Dr. Laurent Frossard. Other parts include:

You can obtain a PDF version of the transcript for this interview, complete with references, at Part_2 – Disadvantages of Osseointegration.pdf.

For your search convenience, we have also included a raw text transcript beneath the embedded video below.

Finally, if you like the video, don’t forget to check out our Key Contacts & Related Information section at the bottom of this article.

Raw Transcript

Wayne:

Welcome back to our series on Osseointegration, Bionic Solutions, and Clinical Outcomes. This is Part 2, Disadvantages of Osseointegration, with our guest, Dr. Laurent Frossard.

Dr. Frossard, do you think patients or prospective patients are well informed of the disadvantages of osseointegration?

Dr. Frossard:

This is an important question. The answer is not always “yes”!

Most of the time, the information available to the public presents predominantly the benefits of osseointegration and other bionic solutions. What could go wrong is often limited to a list of potential mishaps.

The scientific community is partially to blame for that. We have produced far more evidence of advantages than limitations. The pharmaceutical industry wants to know if a medication is safe before to know if it works. And we tend to look at medical devices like bionic solutions the other way around! We are partially responsible for a biased view of the outcomes.

Like you, I am a strong advocate of informing and empowering potential users so that they can make an educated decision about their treatment options with bionic solutions fully aware of all the risks.

Wayne:

What are the main disadvantages of osseointegration?

Dr. Frossard:

In the world of science, we report disadvantages in terms of adverse events. More particularly, we talk about the risk of an adverse event. And this risk represents the likelihood of an event to occur that is expressed in percentage.

We know most adverse events for bionic limbs. However, how often they occur is not always known. Studies estimated that:

  • 6% of cases will experience issues of implant stability. So basically what it means is the growth of the bone around the implant, called osseointegration, will be incomplete and leave the implant loose within the bone. And we are talking about millimeters here.
  • 9% of cases will face bone fractures, we call them periprosthetic fractures. Simply, the bone around the implant breaks when it is not strong enough to handle challenging loads. This often happens during a fall.
  • 31% of cases will deal with breakages of the implant parts. It could be the part into the bone or the part coming out of the residuum. Breakage could be due to poor design of components, overuse of the prosthesis, and catastrophic events like a fall.
  • 41% of cases will experience deep infections. Basically, there is bad stuff near the implant and the bone. It needs to be treated aggressively as early as possible to prevent serious complications.
  • And, finally, 100 % of cases will experience superficial infections. This is a minor infection around the stoma. We know these infections occur often. But I believe they occur even more often than we think because we are not recording them very well.

All these adverse events have several common negative effects for the users. First, they cause pain. They significantly disturb the lifestyle because they limit the usage of the prosthesis for extended durations. Finally, they cost money paid either by the healthcare system and/or the users themselves as out-of-pocket expenses.

Wayne:

I would like to stay on the issues with infections: What are the consequences of these infections?

Dr. Frossard:

The immediate consequence of an infection is pain. I have seen people in real pain, incapable of loading the implant, being basically bedridden for several days.

The thing is that deep infections must be treated early and aggressively. So, one of the consequences is the intake of strong antibiotics. In rare cases, antibiotics must be administrated through an IV in a hospital. In most cases, patients tend to take long courses of strong antibiotics orally at home.

Wayne:

And what is the problem with that?

Dr. Frossard:

This is a very legitimate question. On a one hand, antibiotics allow to overcome infections and prevent possible removal and re-amputation. So, antibiotics are a solution.

On the other hand, regular intake of strong antibiotics can lead to severe health issues in the long run, like building immunity to antibiotics or guts problems.

But I think it might be even worse than that. Users think that they are becoming astute to prevent infections. So, they tend to self-medicate. For example, I’ve heard many people say that they take a course of antibiotics “preventively” before they are exposed to a risky situation, like a trip overseas, for example. So, antibiotics might create substantial problems in the long run as well.

Wayne:

You just mentioned the removal of the implant and re-amputation: how often does that happen?

Dr. Frossard:

We know that adverse events alone or combined can lead to catastrophic failure of the procedure.

Practically, studies indicated that the implant had to be removed in up to 20% of cases.

However, the rate of failure depends on studies and the methodology they used. So, there might be some variations depending on the indications and comorbidity of the patients treated as well as the design of the implant, the surgical team, the rehabilitation program.

In some rare cases, clinicians could remove the implant, wait that the bone heals, and put back another implant. And that could skew reports of failures as well.

Wayne:

Do we know how to prevent these adverse events?

Dr. Frossard:

So, we know that there are some individuals that seem to experience infections more regularly than others. So, they are “infection frequent flyers”!

The bottom line is that the implant sticking out is, indeed, an open stoma exposed to the environment. Some very skilled surgeons find ways to seal the gap between the skin, the bone, and the implant. And that seems to reduce risks of infection.

The worst case is when the bone is completely apparent without direct contact with the skin. This means that the bone will have no blood supply. Sooner or later, the bone will “die” and become brittle. Sadly, it will be a matter of time before something seriously threatening will happen during bodyweight bearing.

Wayne:

You have talked about what we know; is there still a lot that we don’t know?

Dr. Frossard:

Yes. We are consistently gaining better data to assess the strengths and weaknesses of bionic solutions. New registered clinical trials will soon provide further information.

However, there are many fundamental aspects about osseointegration and bionic solutions that we need to understand. However, the good news is that we know what we don’t know!

Wayne:

Dr. Frossard, you’ve given us great insight into the current advantages and disadvantages of bionic solutions involving osseointegration. In Part 3 of this series, we’re going to ask you how we can improve these solutions.

For more information on Dr. Laurent Frossard, please visit his website.

For a complete description of bionic limb technologies, devices, and research, see our complete guides on bionic arms & hands and bionic legs and feet.