Distraction Implantation. A New Technique in Total Joint Arthroplasty and Direct Skeletal Attachment.

backgroundUsing the marrow canal of a tubular bone as a holding compartment for implant stems has been the paradigm in total joint arthroplasty for more than a century, and for direct skeletal attachment of limb prostheses for about forty years. Both interventions rely on the osteogenesis in the inner walls of the marrow canal in a direction radially inwards. It so remains despite the frequent aseptic loosening of the implant stems caused by the resorption of the marrow canal's inner walls which increases the canal's diameter and reduces its capacity to hold the implant. MATERIALS AND

methodsTo improve the bone-device bond, we suggest an implantation methodology that activates positive osteogenic remodeling in the circular direction rather than radially inwards. The rationale is that circular osteogenesis is a component of natural healing of bone fractures and its activating may mitigate the consequences of resorption caused by stress shielding, bone developmental growth and other factors.

resultsCircular osteogenesis occurs in response to the distraction of slots precut into the bone tube. We call this methodology distraction implantation (DI) because of its debt to Ilizarov type distraction osteogenesis (DO). The methodology is accompanied by a design of an implant stem, and has been investigated in a previous pilot animal study.

conclusionDistraction implantation is based on a component of natural healing of bone fractures and therefore has merit to be investigated further.