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Background:Spinal fusion is a commonly used procedure in spinal surgery. To ensure stable fusion, bone graft materials are used. ABM/P-15 (commercial name i-FactorTM Flex) is an available synthetic bone graft material that has CE approval in Europe. This peptide has been shown to improve bone formation when used in devices with fixation or on bone defects. However, the lack of external stability and large graft size make posterolateral lumbar fusion (PLF) a most challenging grafting procedure. This prospective randomized study was designed to evaluate early spinal fusion rates using an anorganic bovine-derived hydroxyapatite matrix (ABM) combined with a synthetic 15 amino acid sequence (P-15) – ABM/P-15 bone graft, and compared with allograft in an uninstrumented PLF model in sheep. The objective of this study was to assess fusion rates when using ABM/P-15 in uninstrumented posterolateral fusion in sheep.Methods: Twelve Texas/Gotland mixed breed sheep underwent open PLF at two levels L2/L3 and L4/L5 without fixation instruments. The levels were randomized so that sheep received an ABM graft either with or without P15 coating. Sheep were euthanized after 4.5 months and levels were harvested and evaluated with a micro-CT scanner and qualitative histology. Fusion rates were assessed by 2D sections and 3D reconstruction images and fusion was defined as intertransverse bridging.Results: There was 68% fusion rate in the allograft group and an extensive migration of graft material was noticed with a fusion rate of just 37% in the ABM/P-15 group. Qualitative histology showed positive osteointegration of the material and good correlation to scanning results. Conclusions: In this PLF fusion model, ABM/P15 demonstrated the ability to migrate when lacking external stability. Due to this migration, reported fusion rates were significantly lower than in the allograft group. The use of ABM/P15 as i-FactorTM Flex may be limited to devices with fixation and bone defects.

The synthetic bone graft material, silicate-substituted calcium phosphate (SiCaP), has been successfully used in spinal fusion surgery. The efficacy of SiCaP-packed 3D-printed lamellar titanium cages used in transforaminal lumbar interbody fusion (TLIF) and lateral lumbar interbody fusion (LLIF) requires investigation. This study evaluated the efficacy of this combination in TLIF and LLIF surgeries treating adult spinal deformities and degenerative disorders. We retrospectively analysed a consecutive case series of 93 adult patients with lumbar degenerative disease or deformity requiring interbody cages who underwent TLIF or LLIF surgery with SiCaP-packed 3D-printed lamellar titanium cages, performed by a single lead surgeon. The primary endpoint was solid fusion 12 months after surgery, assessed using computed tomography. Secondary endpoints were patient-reported outcomes; EuroQOL five dimensions (EQ-5D), visual analogue scale (VAS) for pain (EQ-5D VAS), VAS pain scores for leg and back, and Oswestry disability index (ODI). Complications were recorded. Computed tomography revealed solid fusion in 92/93 (98.9%) patients with good cage integration at the vertebral body interface and no evidence of screw loosening. Patient-reported outcomes significantly improved for all parameters 1 year post-operation. Mean VAS significantly declined 1 year following TLIF surgery (back: −5.5; leg: −6.7) and following LLIF surgery (back: −5.9; leg: −6.9). Mean ODI declined 1 year following TLIF surgery (−43.0) from crippled to minimal disability and following LLIF surgery (−41.2) from severe to minimal disability. SiCaP-packed 3D-printed lamellar titanium cages provided excellent rates of solid fusion in TLIF and LLIF surgeries with notable improvements in patient-reported outcomes.

Objectives The purpose of this study was to evaluate the use of synthetic bone graft material as a filling material at the mandibular symphysis donor site of autologous bone in children. Materials and methods A blinded patient group comprised 20 patients with unilateral (UCLP) or bilateral (BCLP) cleft of lip and palate, all with an indication for alveolar cleft repair. The study took the form of a prospective randomized clinical trial. We used lateral cephalograms for the measurement of the symphyseal donor area defect both peroperatively and at 12 months postoperatively. The data obtained were digitalized and the treatment outcome expressed in numbers. Comparisons with a previous study were made. Histology of biopsies and CT scans were used for visualising bone formation. Results This study demonstrates that the micro-structured, resorbable calcium phosphate ceramic provides good regeneration properties for the repair of a critical size bony defect in children. One year postoperatively, the measurements taken from lateral cephalograms show that there is scarcely any visible residual defect. Histological investigations of the bone biopsies show solid, induced bone formation and almost complete resorption of the micro-structured calcium phosphate. Conclusions The findings of this study (novel in children) indicate that micro-structured resorbable calcium phosphate is an excellent alternative to autologous bone. The digital findings showed a restored donor site defect significantly indicating the efficacy (i.e. osteoconductivity and resorbability) of this bone substitute. The biopsy histology demonstrated the overall presence of newly formed vital bone and the resorption of the bone substitute. Its use for grafting the alveolar cleft is currently researched and it may become the new standard. Clinical relevance As co-morbidity and prolonged operation time at the donor operation site are inherent to the alveolar cleft repair procedure, the use of the described bone substitute is winning progress.

The aim of this study was to evaluate the effect of a biphasic synthetic bone graft material composed of β-tricalcium phosphate (β-TCP) and calcium sulfate (CS) in 12 New Zealand rabbits.A circular bicortical critical-size cranial defect was created in each of 12 rabbits. The defects were grafted with β-TCP/CS. Animals were euthanized at 3 and 6 weeks. Harvested tissue specimens were evaluated histologically and histomorphometrically. Parameters associated with new bone formation and graft resorption were measured and calculated. The results were statistically analyzed using the Mann-Whitney test.Our data demonstrated the biocompatibility of synthetic β-TCP/CS, as no inflammatory response was observed, and no fibrosis was developed between the graft particles and the newly formed bone. Moreover, β-TCP/CS acted as an osteoconductive scaffold that allowed a significant bone regeneration and graft biodegradation with time.In this animal model, synthetic β-TCP/CS proved to be a biocompatible, osteoconductive, and bioresorbable bone graft substitute.

Restoring alveolar bone following tooth extraction or pathological diseases is important, and recent efforts have been made to overcome the use of autografts during dental implantation. Although micro-macroporous biphasic calcium phosphate (MBCPTM) has performed well in orthopedic procedures, few studies have investigated its use in dentistry. Here, we report a greater than eight-year clinical follow-up of bone regeneration using MBCPTM after sinus grafting. MBCPTM technology is a unique mixture of hydroxyapatite and β-tricalcium phosphate, which displays both macroporosity and microporosity. A total of 25 patients (33 implantation sites) were evaluated by X-rays, and their pre-operative and immediate post-operative bone heights were measured. After approximately six months, dental implantation was performed. Subsequently, X rays were performed each year, and bone height was measured. In all cases, radio-opacity of the implantation area decreased with time, indicating resorption and bone ingrowth at the expense of the MBCPTM material. After one year, the implantation area had the appearance of physiological bone and

PURPOSE The purpose of this study was to compare the new bone formation capability of zirconia with those of other synthetic bone grafts. MATERIALS AND METHODS Twelve rabbits were used and four 6-mm diameter transcortical defects were formed on each calvaria. Each defect was filled with Osteon II (Os), Tigran PTG (Ti), and zirconia (Zi) bone grafts. For the control group, the defects were left unfilled. The rabbits were sacrificed at 2, 4, and 8 weeks. Specimens were analyzed through micro computed tomography (CT) and histomorphometric analysis. RESULTS The Ti and Zi groups showed significant differences in the amount of newly formed bone between 2 and 4 weeks and between 2 and 8 weeks (P

A new method of design and manufacturing of bone graft substitutes is introduced. For the first time it is possible to prepare bone graft substitutes with a directed and controlled pore structure. Furthermore, the formation of sophisticated geometries is feasible. First in vitro investigations with cell cultures show a vital cell growing on the synthetic bone graft material. Numerous applications are possible.

Category: Ankle Arthritis Introduction/Purpose: Various treatments have been suggested for the treatment of periarticular cysts in revision total ankle arthroplasty including autograft and allograft bone grafting, polymethylmethacrylate cement, and revision to ankle or tibiotalocalcaneal arthrodesis. This study investigated the rate of osseous reconstitution following treatment with a unique calcium phosphate-calcium sulfate blend. Methods: A retrospective review of all revision total ankle arthroplasty procedures over a 3 year period was performed. 37 patients were identified that had utilized the calcium phosphate-calcium sulfate blend for the treatment of osseous defects. Data on graft location, volume, infection rate, bone reconstitution rate, and further revision procedures were collected. Plain radiographs were used to determine osseous reconstitution, qualified as bony trabeculae present with no lytic area remaining. Patient's average age was 66 years old, revision performed an average of 9.5 years after primary arthroplasty, with an average of 503 (range 99-1333) days of follow up. Results: Grafting of 23 tibial, 23 talar, 7 fibular, and 5 calcaneal bone defects were undertaken. All patients had Agility implants at time of primary arthroplasty. 16 patients had retention of Agility components, with 21 being revised to Inbone 2 implants. An average of 8.25 ml of material was used. Complete bone reconstitution was noted in 24 patients (65%). Incomplete or no bony healing was noted in 9 talus, 2 tibias, and 2 fibulas. Further revision was performed or offered to 7 patients for continued symptoms(19%). No seromas or excessive wound drainage was noted. Conclusion: Grafting of osseous defects for total ankle arthroplasty with a fully synthetic calcium sulfate and calcium phosphate mixture is an effective technique. Caution should be used in its use for patients with talar subsidence, as these have higher rates of failure likely due to its diminished blood supply and smaller surrounding structural support. provide significant long-term structural support. It should not be depended to

Background: Augment™ Bone Graft, a fully synthetic bone graft material composed of recombinant human PDGF and a calcium phosphate matrix (rhPDGF/TCP), has been considered as a possible alternative to autogenous bone graft. Before proceeding with randomized control studies comparing rhPDGF/TCP to autograft bone, a human trial to assess efficacy and safety was required. Materials and Methods: The current study was a prospective, open-label, multi-center trial designed to evaluate rhPDGF in a calcium phosphate matrix (Augment™ Bone Graft). Sixty patients requiring hindfoot or midfoot fusion were prospectively followed for 36 weeks. All patients received 0.9 to 2.7 mg of rhPDGF at the fusion sites and returned for clinical and radiographic review at Day 7 to 14 and Weeks 6, 9, 12, 16, 24, and 36. Computerized tomography (CT) scans of the fusion site were obtained at the 6- and 12-week postoperative appointment, with an additional CT scan at 16 weeks if required. Results: No patients suffered a serious adverse event caused by rhPDGF. CT scan evaluation at 12- to 16-week time periods revealed moderate or complete osseous bridging of 75% (44/59) at 36 weeks. Conclusion: These results indicate that rhPDGF is a safe product and provides clinical/radiographic outcomes that justify the pursuit of randomized controlled studies comparing rhPDGF/TCP to autograft. Level of Evidence: IV, Case Series

Osteochondral defects are common in younger, active patients. Multiple strategies have been used to treat these lesions, including microfracture and osteochondral plug transfer. We describe a patient experiencing chronic knee pain and a full-thickness cartilage defect on the lateral femoral condyle. After failing conservative management and microfracture surgery, the patient underwent osteochondral autograft plug transfer, with backfilling of the donor sites using synthetic bone graft substitute. Initial recovery was uncomplicated until the patient experienced pain following a twist of the knee. Magnetic resonance imaging for the subsequent knee injury revealed poor healing at the donor sites. The donor sites were debrided, and specimens revealed a foreign body giant cell reaction. Donor-site morbidity is of primary concern during osteochondral plug transfer; however, insufficient data exist to support the use of synthetic bone graft material. Our results indicate that off-label use of synthetic bone graft substitute during a primary procedure requires further investigation.

The objective of this study was to develop a synthetic bone graft in a paste form. Reported here are the results of the evaluation of a paste of chitosan glutamate (Protosan®) and hydroxyapatite (referred to as a paste) used in a critical size defect model in rats. Eight-millimeter-diameter cranial defects were made in rat calvaria following a protocol approved by the animal review committee. Five groups were studied: (1) empty control, (2) defect filled with paste only, (3) defect filled with the paste containing bone-marrow aspirate, (4) defect filled with paste containing BMP-2, and (5) defect filled with paste containing osteoblasts cultured from bone-marrow aspirate. The sacrifice intervals were 9 and 18 weeks. Calvaria containing the defect were harvested, and the bone mineral density (BMD) was determined by dual energy X-ray absorptiometry. Push-out strength measurements were also performed. The BMD values of empty control were significantly lower than those of other groups at both 9 and 18 weeks. The mechanical properties, that is, push-out strengths and area under the push-out load and displacement were not significantly different between the samples. Histological examination of Goldner-trichromestained undecalcified sections showed the presence of mineralized bone spicules in the defect areas that were more prominent in those filled with paste and osteoblasts cultured from bone-marrow aspirate. Hence, this study demonstrated that the paste of chitosan glutamate and hydroxyapatite-containing osteoblasts cultured from bone-marrow aspirate would be an effective material to repair bone defects.

Composites of water soluble chitosan and hydroxylspatite (HA) in the paste form were studied for the use as a synthetic bone graft material. HA powder was added to 5% aqueous solution of chitosan in different HA to chitosan ratios. Different techniques were developed to measure the viscosity, setting time, compressive moduli, and push out resistance through cadaver bone holes of the HA-chitosan pastes. An optimum formulation was selected based on the results of these measurements. A system was developed to deliver the pastes to the focal defects in the bone by modifying an arthroscopic syringe.

Foot and ankle surgeons are occasionally confronted with having to fill large defects following excision of osseous lesions. This can prove to be quite challenging to the surgeon in regards to the requirement of large amounts of autogenous, allographic, or synthetic bone graft material. The amount of time spent nonweightbearing postoperatively can be quite prolonged, and the evaluation for tumor recurrence at the graft--host interface is difficult to ascertain. Polymethylmethacrylate has been used extensively in orthopedic surgery for many years in a safe manner for total joint replacement. It has also been used to fill large defects following tumor excision (i.e., giant cell tumor) and as an alternative to bone graft. This article briefly reviews the concepts of using polymethylmethacrylate in this manner and presents the use of polymethylmethacrylate in the treatment of foot and ankle lesions with three case presentations. The authors' purpose for this paper is to simply expand on the current medical literature available regarding the use of polymethylmethacrylate in the foot and ankle and to increase the awareness of foot and ankle surgeons regarding its use as a treatment alternative. A follow-up to this article is planned to present a larger patient population, longer term follow-up, and outcomes data.