Previous clinical studies have shown the efficacy of a foreign body-induced membrane combined with bone autograft for the reconstruction of traumatologic or pathologic large bone defects or, bone non union. This membrane, rich in mesenchymal stromal cells (MSC), avoids bone autograft resorption and promotes consolidation by revascularisation of the bone and secretion of growth factors. Reconstruction requires two different surgical stages: firstly, insertion of a cement spacer in the defect, and secondly, removal of the spacer, preservation of the foreign body-induced membrane and filling of the cavity by bone autograft. The optimal time to perform the second surgical stage remains unclear. So, we aimed to correlate bone healing and, phenotype and function of cells isolated from the induced membrane, in patients whose second surgery was performed on average after 6 months (i.e. beyond the recommended time of one month). Cell phenotype was determined by flow cytometry and cell function by: alkaline Phosphatase enzyme activity, secretion of calcium and von Kossa staining. Second, using histological and immunohistochemistry studies, we aimed to determine the nature and function of induced membrane over time. Seven patients were included with their consent. Results showed Treated patients achieved in all cases bone union (except for one patient) and in in vitro and histology and immunohistochemistry gave some indications which need to be completed in the future. First, patient age seemed to be an indicator of bone union speed and recurrent infection, appeared to influence in vitro MSC osteogenic potential and induced membrane structure. Second, we reported, in bone repair situation, the commitment over time in osteogenic lineage of a surprising multipotent tissue (induced membrane) able of vascularisation/ osteogenesis/ chondrogenesis at a precocious time. Finally, best time to perform the second stage (one month) could be easily exceeded since bone union occurred even at very late times.
Used routinely in maxillofacial reconstructive surgery, the chondrocostal graft is also applied to hand surgery in traumatic or pathologic indications. The purpose of this overview was to analyze at long-term follow-up the radiological and histological evolution of this autograft, in hand and wrist surgery. We extrapolated this autograft technique to the elbow by using perichondrium. Since 1992, 148 patients have undergone chondrocostal autograft: 116 osteoarthritis of the thumb carpometacarpal joint, 18 radioscaphoid arthritis, 6 articular malunions of the distal radius, 4 kienbock's disease, and 4 traumatic loss of cartilage of the proximal interphalangeal (PIP) joint. Perichondrium autografts were used in 3 patients with elbow osteoarthritis. Magnetic Resonance Imaging (MRI) was performed in 19 patients with a mean follow-up of 68 months (4–159). Histological studies were performed on: Whatever the indication, the reconstruction by a chondrocostal/ostochondrocostal or perichondrium graft yielded satisfactory clinical results at long-term follow-up. The main question was the viability of the graft.
Despite the strong mechanical strain in the hand and wrist, chondrocostal graft is a biological arthroplasty that is trustworthy and secure over the long term, although it can cause infrequent complications inherent to this type of surgery. Despite the inevitable histological modification, the cartilage remains alive and is of satisfactory quality at long term follow-up and fulfills the requirements for interposition and reconstruction of an articular surface. The perichondrium graft constitutes a new arsenal to cure cartilage resurfacing. The importance of perichondrium for the survival of the grafted cartilage, as previously reported, as well as its role in resurfacing, is being investigated.
20 cases of bone defect have been treated by the induced membrane technique avoiding allograft, microsurgery and amputation 9 cases of long bone defect (humerus and 2 bones arm) and 11 cases of bone defct at the hand have been included in this multicentric prospective study (3 centers). 11 cases were traumatic, 7 cases were septic non union and 2 cases were tumor. At hand level's bone reached at least one phalanx, and for long bone the mean defect was 5cm (3–11). All cases were treated by the induced membrane technique which consists in stable fixation, flap if necessary and in filling the void created by the bone defect by a cement spacer (PMMA). This technique needs a second stage procedure at the 2nd month where the cement is removed and the void is filled by cancellous bone. The key point of this induced membrane technique is to respect the foreign body membane which appeared around the cement spacer and which create a biologic chamber after the second time. Bone union was evaluated prospectively in each case by an surgeon not involved in the treatment by Xray and CT scan. Failure was defined as a non union at 1 year, or an uncontrolled sepsis at 1 month.Introduction
Material and Methods
Properties of human amniotic membrane are particularly interesting. To use it as an Advanced Therapeutic Medicinal Product in bone surgery, we are evaluating its association with a potentially osteoinductive scaffold. The human Amniotic Membrane (hAM) is known to have a good potential to help the regeneration of tissues. It has been used for 100 years in many medical disciplines because of its properties: a membrane containing stem cells and growth factors, with low immunogenicity and anti-microbial, anti-inflammatory, anti-fibrotic and analgesic properties. Moreover, previous published data showed the possibility of We aim to use hAM as an Advanced Therapeutic Medicinal Product for bone repair to treat large defects or pseudarthrosis. So we are studying the association of hAM with nanofiber jet sprayed polycaprolactone (PCL) scaffolds and the possibility to induce its osteodifferenciation.Summary
Introduction
Human amniotic membrane has interesting properties for regenerative medicine. To use it as an Advanced Therapeutic Medicinal Product in bone surgery, we are evaluating: the necessity of its osteodifferentiation and the impact on immunogenicity; its optimal condition for storage. The human Amniotic Membrane (hAM) is known to have a good potential to help the regeneration of tissues. It has been used for 100 years in many medical disciplines because of its properties: a flexible scaffold containing stem cells and growth factors, with low immunogenicity and anti-microbial, anti-inflammatory, anti-fibrotic and analgesic properties. Previous published data showed the possibility of in vitro osteodifferentiation of the whole tissue. We aim to use this «boosted membrane» as an Advanced Therapeutic Medicinal Product for bone repair to treat large defects or pseudarthrosis, so, we are studying: The necessity to osteodifferentiate the tissue and its consequence on the immunogenicity; Its in vivo osteogenic potential; The effects of the cryopreservation on cell viability and function.Summary
Introduction
