Treatment of Atrophic Nonunion Fractures by Autologous Mesenchymal Stem Cell Percutaneous Grafting

Treatment of Atrophic Nonunion Fractures by Autologous Mesenchymal Stem Cell Percutaneous Grafting. A Randomized, Double-blind, Controlled Study

Bone fractures heal most of the time particularly well and without complications. The solidification takes rarely more than two to three months. The wound healing depends greatly on a good blood supply and needs several steps. These processes culminate in a new mass of heterogeneous tissue which is known as the fracture callus. Unfortunately, 2%-5% bone fractures cannot achieve a proper solidification and between the ununited fragments a scar tissue appears. This incorrect healing induces pain and even infections. When this situation persists more than 6 months, it is referred to as nonunion fracture, which will require some form of intervention to stimulate the natural healing process of the body. First of all, good surgical techniques with stable immobilization should be applied and local infection should be excluded. Then stimulation of the callus is required. Cell therapy with bone marrow cells has emerged as a promising new approach for bone regeneration. Animal studies as well as preliminary human studies have shown that Mesenchymal Stem Cells, a particular kind of stem cells isolated from the bone marrow, could induce callus formation when injected in the nonunion site of a broken bone.

In this study the investigators aim at determining whether Mesenchymal Stem Cells (MSC) isolated from the patient's bone marrow and injected in the nonunion site could be a safe and effective treatment for nonunion fractures. Patients will be randomized in two groups; one injected with Mesenchymal Stem Cell and the other injected with placebo. The investigators seek also to know how long it takes to develop the callus formation and whether there is a partial or a complete callus formation.

Inclusion Criteria:

• Male or female; female patients must use a reliable contraception method
• Age ≥ 18 years
• Fracture having no radiological callus after 6 months and absence of any hypertrophic bone reaction.
• No sepsis
• Good skin covering
• Be able and willing to participate in the study
• Written informed consent

Exclusion Criteria:

• Evidence of malignancy (except non-melanoma skin cancer) in the past five years
• Pregnancy or breastfeeding
• Patient positive by serology or PCR for HIV, hepatitis B or C infection
• Insufficient reduction of the fracture with displaced fragments
• Evidence of local sepsis by clinical signs, biological parameters (CRP) and/or positive isotopic scan using Indium-labelled leucocytes