Currently Osseointegration Prosthetic Limb or OPL and the Osseointegrated Prosthesis for the Rehabilitation of Amputees or OPRA are the only versions commercially available to date. The OPL device utilizes a three dimensional method of Osseointegration which is common in joint replacement procedures. The OPRA system utilizes screw fixation which offers a one dimensional interface and is how dental implants are secured. In a one dimensional system you obtain bony on-growth but with a three dimensional system bony in-growth is achieved. With bony in-growth, bone doesn’t simply adhere to the outer surface of the implant, it actually penetrates the device; thus enabling minute blood vessels and nerves to form within the newly created structure. These new blood vessels promote healing within this structure, unlike a one dimensional system where there is no significant integration between bone and the implant itself.
In 1990 the Germans developed a three dimensional Integral Leg Prosthesis or ILP implant that was utilized successfully until it was essentially replaced with the more advanced OPL device. Although the ILP device is still utilized in a limited capacity in both the Netherlands and Australia.
There are a few differences between the German ILP device and the newer OPL implant. They both share a three dimensional interface, although the ILP device utilizes a titanium coated Chrome Cobalt stem; where as the OPL device utilizes a stem made of a solid titanium core. The OPL device has moved away from simply offering a three dimensional titanium coated interface. The implant has been modernized and now offers one immediate stabilization through the use of concepts seen in modern day cement-less hip replacement implants. By applying the latest in medical technology (which is based upon hip replacement Bio Materials), there is no longer a need for patients to wait 6 to 8 weeks between two surgeries to become mobile again. Today, most patients are mobilizing in ten to fourteen days after a single stage procedure.
In comparison, the Swedish screw fixation (OPRA) device has a prolonged rehabilitation protocol that doesn’t allow full mobilization for up to 12 months and after a two stage procedure.
This site provides information and links regarding all versions of OI, so you can choose the version that best suits you, if at all. Even though OPRA is the original implant, the Direct Fixation Implant and ITAP versions are conducting some promising research in areas that the others don’t currently offer. Combined with unrelated research being conducted in the United States by Hugh Herr, who heads the Biomechatronics research group at the MIT Media Lab and OI research that is being conducted by Dr Roy Bloebaum at the University of Utah. One can foresee things getting pretty interesting in the near future.
* As of August 2013 Dr Ronald Hillock of Las Vegas, Nevada performed OI surgery on a 63 year old Above Knee Amputee under custom device guidelines but his work is not a part of any FDA approved study and there is no team or established rehabilitation protocol behind his work. As the procedure has not been performed in a significant number of patients that would enable one to develop a proper protocol. Patients seeking this route are essentially agreeing to be guinea pigs of sorts; with no established protocol in the event a problem arises. This custom implant is sold by Signature Orthopedic in Sydney, Australia. Although there is no documentation as to where the device is actually being manufactured.
The Las Vegas patient is NOT the first to undergo Osseointegration surgery in the US. There is a well respected Orthopedic surgeon in Utah who was the first to implant an American with an OI device under the same custom device guidelines. Interesting enough, he is also responsible for implanting the first Canadian with an Ossseointegrated device.
The unnamed surgeon believes it inappropriate to go public without proper implant follow up. So for now, his work remains unpublished. Although he is utilizing a modified compress device from BioMet, which was initially designed for bone tumor applications. The device has since been utilized by a few others but in a limited capacity; as the procedure falls under the Fda custom device guidelines which limits the number of procedures to five per year under this classification.