Overcoming the Limitations of Allograft in Impaction Bone Grafting for Revision Arthroplasty
Lead Research Organisation:
University of Southampton
Department Name: Development Origin of Health and Disease
Abstract
The replacement of lost bone is a major clinical and socio-economic need, particularly in the fields of revision arthroplasty, spinal and trauma surgery. Often, a lack of sufficient host (own or autogenous) bone precludes the universal use of autogenous bone while the use of donor (allogeneic) bone carries risks of rejection and infection. Bone marrow contains stem cells (skeletal stem cells), which can be isolated and can be readily expanded, while retaining their ability to form a variety of tissues like bone and fat.
Given the demographic challenge of an ageing population, the development of strategies to exploit the potential of bone progenitors which can give rise to cells of the osteogenic lineage, offers a compelling approach to augment bone formation to replace or restore the function of traumatised or degenerated bone.
We propose a unique programme to create a living composite of bone progenitor cells and a synthetic scaffold together with a new innovative process for placing the synthetic polymer scaffold and cells in the hip cavity ( a process of vibration impaction bone grafting)that can be applied in orthopaedic applications requiring new bone stock. We will show in this work the ability of bone progenitor cells together with an optimised synthetic scaffold and an innovative vibration impaction process our ability to augment bone formation in impaction bone grafting. To prove our concept, we will use a standard clinical orthopaedic procedure called femoral impaction grafting wherein a new prosthesis is needed to replace a degenerated hip implant and needs bone stock.
Given the demographic challenge of an ageing population, the development of strategies to exploit the potential of bone progenitors which can give rise to cells of the osteogenic lineage, offers a compelling approach to augment bone formation to replace or restore the function of traumatised or degenerated bone.
We propose a unique programme to create a living composite of bone progenitor cells and a synthetic scaffold together with a new innovative process for placing the synthetic polymer scaffold and cells in the hip cavity ( a process of vibration impaction bone grafting)that can be applied in orthopaedic applications requiring new bone stock. We will show in this work the ability of bone progenitor cells together with an optimised synthetic scaffold and an innovative vibration impaction process our ability to augment bone formation in impaction bone grafting. To prove our concept, we will use a standard clinical orthopaedic procedure called femoral impaction grafting wherein a new prosthesis is needed to replace a degenerated hip implant and needs bone stock.
Technical Summary
Each year in the UK there are over 50,000 primary hip replacement operations at a cost of #250million. With an increasing ageing population, this is set to rise to 65,000 by 2026 of which 30-50% will require subsequent revision surgery. In a large proportion, bone augmentation will be necessary. We have recently demonstrated the stimulation of new bone formation in a small animal in vivo model of impaction bone grafting. We proved that highly porous polymer scaffolds could mechanically shield skeletal or mesenchymal stem cells (MSCs) during impaction. After impaction the MSCs stimulated angiogenesis and augmented new bone formation. In parallel we have been developing protocols to improve the compaction process using vibration compaction strategies as the risk of femoral fracture in impaction bone grafting of the femur is substantial. Our approach can be used to extend or replace auto and allograft in revision hip arthroplasty. We require funding to transfer the concept of an allograft synthetic bone extender and vibration impaction processes to a larger clinically releavant ovine model of hip revision arthroplasty as a precursor for clinical trials.