Bone non union and long bones pseudarthrosis : contribution of BMPs

Long bones fractures are complicated by non union in 10 % of thecases. In the “risk” groups, the non union rate can reach 30 %. Inaddition, evolution is unforeseeable on sight of the septic nature ofthe pseudarthrosis, which worsens the prognosis and increases morbidity.Bone reconstruction in case of bone defect, remains an unresolvedproblem today with the classic techniques. Amputation isstill a topical solution in these non union problems. The knowledgeof the factors intervening in the bone reconstruction and the molecularmechanisms are crucial. It is well known that the osteoregenerationdepends on 3 actors: the osteoregenerative cells(mesenchymal stem cells, osteoblasts), the osteoinductive proteinsand the carrier. The autograft gathers the whole of these actors:cells and growth factors contained within a matrix. The BoneMorphogenetic Proteins (BMP), are one of these growth factors.They are now usable in clinical practice and can be added duringthe treatment of a resistant non union. What is the mode of action ofthese growth factors? What are their advantages and their drawbacks?Are they safe? Are they effective and, above all, are theysuperior to the classic techniques in the treatment of the long bonesnon union? Is it possible to compare resistant cases of non unionwith bone defect or/ and septic complications after iterative procedure?How to obtain control group in such situations ?