Osseointegration is derived from the Greek ‘osteon’ meaning bone, and the Latin ‘integrare’, which means to make whole. It is defined as the direct contact between living bone and the surface of a synthetic, often titanium based, implant.
Osseointegration’s original application was in bone and joint replacement surgeries and not only has it dramatically enhanced these surgeries and their outcomes but now it is also used to vastly improve the quality of life for amputees.
Sir John Charnley pioneered Hip Replacement surgery in 1962. His design and approach involved fixing the replacement prosthesis to the bone, which he based on a dental practice of using bone cement. His revolutionary technique is still used today.
The concept of osseointegration in dentistry first started in 1965 with Professor Per-Ingvar Branemark who threaded trans-oral titanium implants into the mandible and maxilla (the bones of the upper and lower jaw) to act as anchorage for dental prostheses.
In 1990, based on a successful technique developed by his father, Brånemark performed the first transcutaneous femoral intramedullary prosthesis on an above knee amputee with an A 12-cm screw-fixation titanium threaded device.
A non weight-bearing period of six to 12 months was applied to allow proper osseointegration.
Clinically osseointegration for amputees has been used since 1995, utilising a skeletally integrated titanium implant that is connected through an opening in the stump (stoma) to an external prosthetic limb. The traditional suction prosthesis is no longer required and perfect fit is achieved via a torque controlled knee connector.
This allows for direct contact to the ground, which provides greater stability, more control and minimises energy exerted.
There is a large debate in the orthopaedic community between using Screw Fixation or Fit and Fill Principle in the absence of bone cement. To date clinical data from hip arthroplasty has shown superior results with the press fit implants compared to those replaced using screw fixation. This is because press fit implants allows for much earlier mobilisation, better fixation and long term stability of the implant.
In 1982 ESKA Implants Lübeck/Germany, now Orthodynamics, pioneered a 3D macro porous surface structure that allowed for ingrowth between the bone and implant surface.
These images show the process of bone ingrowth into the spongiosa metal.
After the successful osseointegration results of the Spongiosa metal in hip and knee arthroplasty, Orthodyamics produced the OGAP-OPL implant in 1990. This implant was first implanted into the femoral canal of a young man who had lost his leg in a motorcycle accident.