Abstract. Introduction. Bone grafts are utilised in a range of surgical procedures, from joint replacements to treatment of bone loss resulting from cancer. Decellularised
Summary Statement. Supercritical fluid (SCF) sterilization produces clean and osteoconductive
Introduction and Objective. In recent years, along with the extending longevity of patients and the increase in their functional demands, the number of annually performed RSA and the incidence of complications are also increasing. When a complication occurs, the patient often needs multiple surgeries to restore the function of the upper limb. Revision implants are directly responsible for the critical reduction of the bone stock, especially in the shoulder. The purpose of this paper is to report the use of
Introduction. Cancellous and cortical bone used as a delivery vehicle for antibiotics. Recent studies with cancellous bone as an antibiotic carrier in vitro and in vivo showed high initial peak concentrations of antibiotics in the surrounding medium. However, high concentrations of antibiotics can substantially reduce osteoblast replication and even cause cell death. Objectives. To determine whether impregnation with gentamycine impair the incorporation of
Secondary sterilisation of
There have been conflicting reports on the effects of gamma irradiation on the material properties of cortical
The BMP-2 content and bone forming potential of 2 leading allograft products (OsteoAMP® and Osteocel® Plus) was tested across 3 commercially available lots. Surprisingly, there was no BMP-2 content associated with the cells contained within Osteocel® Plus. OsteoAMP® contained greater than 1000 times the overall BMP-2 content than Osteocel® Plus. Correspondingly, Osteocel® Plus did not form new bone at any timepoint in the 12 week in vivo study while OsteoAMP® had increasing new bone formation at each sequential timepoint. Interestingly, the highest cellularity of Osteocel® Plus was just prior to implant at t0, decreasing at each timepoint, decreasing further at the terminal endpoint of the study at 12 weeks (82% of cells had died or migrated). Conversely, the cellularity of OsteoAMP® increased at each timepoint. Implants containing living cells are often characterised by the orthobiologics industry as ‘osteogenic’. The positive function and ultimate fate of these cells has been assumed with little to no proof of efficacy. In this study we compare the bone forming ability of the market leading stem cell product claiming osteoinductivity as well as osteogenicity, Osteocel® Plus, against the market leading allograft derived growth factor product, OsteoAMP® which claims osteoinductivity but contains no viable cells. The goal of the study is to determine if a cellular product will form new bone or produce a false positive when evaluated histomorphometrically using an osteoinductive control over time in vivo. Additionally, the osteoinductive potential from each product will be quantified by in vitro by measurement of BMP-2 content via ELISA.Summary
Introduction
Impacted
Periosteal mesenchymal stem cells (PMSC) are an emerging niche of stem cells to enhance bone healing by tissue engineering process. They have to be differentiated into osteoprogenitors in order to synthesize new bone matrix. In vitro differentiation with specific differentiation medium (DM) is not exactly representative of what occurs in vivo. The interaction between PMSC and growth factors (GF) present in biological matrix is somewhat less understood. The goal of this study is to explore the possibility of spontaneous PMSC differentiation in contact with different biological matrices without DM. 500.000 porcine PMSC were seeded on 6-well plates and cultured with proliferation medium (PM). When reaching 80% confluence, biological samples (n=3) of demineralized bone matrix (DBM), decellularized porcine
In 2021 the bone grafting market was worth €2.72 billion globally. As
Many factors have been reported to affect the functional survival of OCA transplants, including chondrocyte viability at time of transplantation, rate and extent of
Despite the growing success of OCA transplantation in treating large articular cartilage lesions in multiple joints, revisions and failures still occur. While preimplantation subchondral drilling is intended to directly decrease allograft bioburden and has been associated with significant improvements in outcomes after OCA transplantation, the effects of size, number, and spacing of subchondral bone drill sites have not been fully evaluated. This study aimed to investigate the effects of drill size with or without pulse-lavage of OCA subchondral bone by quantifying remnant marrow elements using histomorphometry. With IRB and ACUC approvals, human and canine OCAs were acquired for research purposes. Portions of human tibial plateau OCAs acquired from AATB-certified tissue banks that would otherwise be discarded were recovered and sectioned into lateral and medial hemiplateaus (n=2 each) with a thickness of 7 mm. Canine femoral condyles and tibial plateaus were split into lateral and medial components with a thickness of 7 mm (n=8). Using our clinical preimplantation preparation protocol, holes were drilled into the subchondral bone of each condyle and hemiplateau OCA using either 1.6 mm OD or 3.2 mm OD drill bits from the cut surface to the cortical subchondral bone plate. One femoral condyle and one hemiplateau per drill bit size were pulse-lavaged while the corresponding OCAs were not. The mean total %-fill remaining marrow elements for each treatment group was calculated. Little to no quantifiable bone marrow element retention was noted to remain within the subchondral bone of human or canine OCA specimens after subchondral drilling of
Cervical and lumbar spine fusion procedures are increasing every year. Nonetheless, these procedures are associated with high infection rates, resulting in additional cost burden. The conundrum of achieving efficient spinal fusions with minimum complications requires an ideal bone graft with osteoconductive, osteoinductive, osteogenic and structural characteristics. Synthetic bone graft substitutes with or without autograft,
Summary. 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. Introduction. 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. Materials and Methods. HAM from cesarean delivery were provided by a local bank of tissue. 4 groups of hAM were performed:. Group 1: non treated (fresh hAM);. Group 2: cryopreserved hAM;. Group 3: cultured hAM in osteogenic medium 3 weeks;. Group 4: cultured hAM in osteogenic medium 3 weeks and then cryopreserved. Cell viability was measured and the osteodifferentiation was revealed by Alizarin Red and von Kossa staining on whole tissue and on histological sections. We grafted these 4 groups of hAM in an ectopic murine model (subcutaneously) either alone (to evaluate its resorption and its immunological tolerance) or wrapped around bone substitute (to observe its osteogenic potential). We explanted grafted tissues after 1, 2, 4 and 8 weeks and performed histological and immunological studies. Results. To date, in vitro studies showed: A macroscopic mineralization of hAM in group 3. Different cell viability according to the groups that apparently doesn't alter the osteogenic potential. A tensile strength dependent on the time of cryopreservation and the type of cyropreservant used. In vivo macroscopic studies showed: no immunological reaction neither resorption of hAM after 4 weeks of implantation in all the groups and a tissue calcification in group 3. In vivo microscopic studies showed: the presence of hAM in a vascularised fibrous capsule; the bilayer hAM structure is still observed without sign of inflammation. Discussion. We confirmed the in vitro osteodifferentiation of hAM reported by others. First in vivo experiments let us think that the tissue keeps its low immunogenicity after its osteodifferentiation; the histological results will confirm it. The definition of optimal conditions for cryopreservation is in progress. At the end of this proof of concept, we will able to conclude if hAM can be used as an
We investigated the antibiotic concentration in fresh-frozen femoral head allografts harvested from two groups of living donors. Ten samples were collected from patients with osteoarthritis of the hip and ten from those with a fracture of the neck of the femur scheduled for primary arthroplasty. Cefazolin (1 g) was administered as a pre-operative prophylactic antibiotic. After storage at −80°C for two weeks the pattern of release of cefazolin from morsellised femoral heads was evaluated by an in vitro broth elution assay using high-performance liquid chromatography. The bioactivity of the bone was further determined with an agar disc diffusion and standardised tube dilution bioassay. The results indicated that the fresh-frozen femoral heads contained cefazolin. The morsellised bone released cefazolin for up to four days. The concentration of cefazolin was significantly higher in the heads from patients with osteoarthritis of the hip than in those with a fracture. Also, in bioassays the bone showed inhibitory effects against bacteria. We concluded that
The role of bone-graft extenders in impaction revision surgery is becoming increasingly important. Tricalcium phosphate and hydroxyapatite have been shown to be both biocompatible and osteoconductive, yet many surgeons remain reluctant to use them. The difficulty in handling bone-graft extenders can be partly alleviated by using porous particles and adding clotted blood. In an in vitro model we measured the cohesive properties of various impaction graft mixes. Several factors were evaluated including the use of pure bone graft compared with mixes with extender, washing the bone and the addition of clotted blood. Our findings showed that pure
To prevent infections after orthopedic surgery, intravenous antibiotics are administered perioperatively. Cefazolin is widely used as the prophylactic antibiotic of choice. Systemic antibiotic therapy may however be less effective in longstanding surgery where
In impaction grafting of contained bone defects after revision joint arthroplasty the graft behaves as a friable aggregate and its resistance to complex forces depends on grading, normal load and compaction. Bone mills in current use produce a distribution of particle sizes more uniform than is desirable for maximising resistance to shear stresses. We have performed experiments in vitro using morsellised
