Bone Core Research Articles

Trans-4 Portal as a New Portal for Accessing the Lunate in Wrist Arthroscopy: a Cadaveric Study

BackgroundEvolving wrist arthroscopy requires creating new portals, and creating portals reciprocally leads to increased indications for arthroscopic wrist procedures. To facilitate access to the lunate bone and fossa for new arthroscopic procedures, a new portal was used. This is a cadaveric study of this portal.ObjectivesIn this cadaveric study, we evaluated a portal in wrist arthroscopy for procedures involving the lunate bone and lunate fossa.Materials and MethodsSeventeen wrists from 10 fresh cadavers were included in this study. After diagnostic arthroscopy, a portal (Trans-4) was made through the fourth extensor compartment, exactly along the lunate’s long axis under direct visualization from the 3-4 portal. Strand retractors were used to protect the extensor tendons and posterior capsule. Lunate bone core decompression and osteoscopy were done through the portal. At the end of the procedure, the position of the decompression hole in the lunate and any possible injury to the extensor tendons, distal radius cartilage, lunate cartilage, and perilunate ligaments were investigated.ResultsLunate bone decompression was performed successfully in all cases using the trans-4 portal. In 15 wrists, the lunate hole was located in the middle third. In the other two wrists, it was located slightly radial in one case and slightly on the ulnar side in the other case. There was no cortical penetration during decompression, and no extensor tendon, superficial nerve branches, or peri-lunate ligament injuries were observed.ConclusionsThe trans-4 portal could be a safe working portal in wrist arthroscopy that enables access to the lunate bone and lunate fossa.

Clinical, Radiographic, and Histologic Evaluation of Maxillary Sinus Lift Procedure Using a Highly Purified Xenogenic Graft (Laddec(®)).

ABSTRACTObjectivesThe aim of this study was to evaluate the clinical, radiographic and histologic results when a highly purified xenogenic bone (Laddec®) was used as grafting material in maxillary sinuses.Material and MethodsIn fifteen patients requiring unilateral maxillary sinus augmentation, the grafting procedure was performed with Laddec®. Forty-two implants were installed after a 6 month healing period. The height of the augmented sinus was measured radiographically immediately after augmentation and postoperatively up to 36 months. At the time of implant placement, a bone core was harvested in each patient for histological examination.ResultsThe cumulative implant survival rate was 97.6%. The original height was 3.65 (SD 0.7) mm and the augmented sinus height was 13.8 (SD 1.4) mm after the surgery. The reduced height of grafted xenogenic material (RDL) at the implant insertion was 0.83 (SD 0.38) mm, and at the final postoperative visit was 0.91 (SD 0.25) mm, showing no significant correlation with the follow-up periods by Spearman’s test (P = 0.118). In addition, no significant difference in the RDL was observed according to the site of implantation (P = 0.682). The mean implant marginal bone loss was 0.38 (SD 0.24) mm. Histological analysis showed the bone cores were composed of 64.72 (SD 3.44)% newly formed bone, 17.41 (SD 2.02)% connective tissue, 16.93 (SD 2.83)% residual graft particles, and 0.94 (SD 0.11)% inflammatory cells.ConclusionsAccording to our data, the highly purified xenogenic bone (Laddec®), used as graft material in the sinus lift procedure, may create adequate bone volume, and appropriate osseointegration of dental implants.

Histological and micro-computed tomographic observations after maxillary sinus augmentation with porous hydroxyapatite alloplasts: a clinical case series.

BackgroundIt is important to visualize the phenomenon which occurs in actual clinical cases to decide the timing of implant placement subsequently after sinus graft. Although several clinical cases of bone augmentation using xenograft have been evaluated, the number of those reports which have described bone remodeling by alloplasty are not sufficient.FindingsIn the present report, to investigate bone remodeling histologically after maxillary sinus augmentation with porous hydroxyapatite alloplast, bone cores from the sinus floor of three female nonsmoking patients (aged 64–73 years) were collected 6 months after sinus lift surgery, embedded in methyl methacrylate resin, and prepared by conventional methods. Bone architecture and graft residues were evaluated by micro-computed tomography of the same specimens. Hematoxylin–eosin and Villanueva–Goldner staining revealed mature osteoblasts and multinucleated osteoclasts on the grafted sinus floor and surface of residual hydroxyapatite particles. The particulate interspace was partially filled with osteoid and calcified tissue and showed active vascularization.ConclusionThe results suggested that bone regeneration and angiogenesis within and between porous hydroxyapatite particles were sufficiently found after 6 month histologically in the grafted sinus floor.Electronic supplementary materialThe online version of this article (doi:10.1186/s40064-016-1885-2) contains supplementary material, which is available to authorized users.

Ridge Preservation Using Composite Alloplastic Materials: A Randomized Control Clinical and Histological Study in Humans.

To evaluate (clinically, histologically, and histo-morphometrically) the use of composite materials (Biphasic calcium sulphate [BCS] with β Tri-Calcium Phosphate (β-TCP) and Hydroxyapatite [HA]) in extraction socket sites and compare it to un-disturbed natural healing. Prospective clinical trial of 36 patients (40 extraction sockets) were randomly assigned to either test or control group. Alveolar ridge horizontal dimension was measured in the middle of the socket at crest and 3 and 6 mm subcrestally. Crestal vertical height was measured at baseline surgery and at 4 month re-entry, at which time bone core biopsies were harvested from the center of the edentulous ridge. Histo-morphometric evaluation of the samples was performed using hematoxylin & eosin stains and morphometric software. The change in horizontal ridge width was higher in the control compared to the experimental group: 2.28 ± 2.36 mm versus 0.03 ± 2.32 mm (p = .007) at -3 mm and 2.28 ± 2.43 versus 0.035 ± 3.05 (p = .02) at -6 mm, for the experimental and control sites, respectively. The vertical distance form bone crest to neighboring horizontal line interconnecting the neighboring teeth was minimal in both groups (0.307 ± 2.01 mm versus 0.14 ± 2.03 mm [p = 0.41]). Residual scaffolds occupied 15.99 ± 11.4% of the volume in the grafted (test) sites while bone area fraction was not statistically different among the groups (47.7 ± 10.6% versus 52.6 ± 11.6%, test versus control, respectively p = .39). The percentage of connective tissue in the control group was significantly higher that test group (36.3 ± 19.4% versus 46.7 ± 10.6% test versus control, respectively, p = .013). Ridge preservation technique using a combination of two synthetic bone grafts β-TCP and HA with BCS resulted in greater stability in the horizontal dimension after 4 months.

Screw insertion in trabecular bone causes peri-implant bone damage

Secure fracture fixation is still a major challenge in orthopedic surgery, especially in osteoporotic bone. While numerous studies have investigated the effect of implant loading on the peri-implant bone after screw insertion, less focus has been put on bone damage that may occur due to the screw insertion process itself. Therefore, the aim of this study was to localize and quantify peri-implant bone damage caused by screw insertion.We used non-invasive three-dimensional micro-computed tomography to scan twenty human femoral bone cores before and after screw insertion. After image registration of the pre- and post-insertion scans, changes in the bone micro-architecture were identified and quantified. This procedure was performed for screws with a small thread size of 0.3mm (STS, N=10) and large thread size of 0.6mm (LTS, N=10).Most bone damage occurred within a 0.3mm radial distance of the screws. Further bone damage was observed up to 0.6mm and 0.9mm radial distance from the screw, for the STS and LTS groups, respectively. While a similar amount of bone damage was found within a 0.3mm radial distance for the two screw groups, there was significantly more bone damage for the LTS group than the STS group in volumes of interest between 0.3–0.6mm and 0.6–0.9mm.In conclusion, this is the first study to localize and quantify peri-implant bone damage caused by screw insertion based on a non-invasive, three-dimensional, micro-CT imaging technique. We demonstrated that peri-implant bone damage already occurs during screw insertion. This should be taken into consideration to further improve primary implant stability, especially in low quality osteoporotic bone. We believe that this technique could be a promising method to assess more systematically the effect of peri-implant bone damage on primary implant stability. Furthermore, including peri-implant bone damage due to screw insertion into patient-specific in silico models of implant-bone systems could improve the accuracy of these models.

Combined exposure to big endothelin-1 and mechanical loading in bovine sternal cores promotes osteogenesis

Increased bone formation resulting from mechanical loading is well documented; however, the interactions of the mechanotransduction pathways are less well understood. Endothelin-1, a ubiquitous autocrine/paracrine signaling molecule promotes osteogenesis in metastatic disease. In the present study, it was hypothesized that exposure to big endothelin-1 (big ET1) and/or mechanical loading would promote osteogenesis in ex vivo trabecular bone cores. In a 2×2 factorial trial of daily mechanical loading (−2000με, 120cycles daily, “jump” waveform) and big ET1 (25ng/mL), 48 bovine sternal trabecular bone cores were maintained in bioreactor chambers for 23days. The bone cores' response to the treatment stimuli was assessed with percent change in core apparent elastic modulus (ΔEapp), static and dynamic histomorphometry, and prostaglandin E2 (PGE2) secretion. Two-way ANOVA with a post hoc Fisher's LSD test found no significant treatment effects on ΔEapp (p=0.25 and 0.51 for load and big ET1, respectively). The ΔEapp in the “no load + big ET1” (CE, 13±12.2%, p=0.56), “load + no big ET1” (LC, 17±3.9%, p=0.14) and “load + big ET1” (LE, 19±4.2%, p=0.13) treatment groups were not statistically different than the control group (CC, 3.3%±8.6%). Mineralizing surface (MS/BS), mineral apposition (MAR) and bone formation rates (BFR/BS) were significantly greater in LE than CC (p=0.037, 0.0040 and 0.019, respectively). While the histological bone formation markers in LC trended to be greater than CC (p=0.055, 0.11 and 0.074, respectively) there was no difference between CE and CC (p=0.61, 0.50 and 0.72, respectively). Cores in LE and LC had more than 50% greater MS/BS (p=0.037, p=0.055 respectively) and MAR (p=0.0040, p=0.11 respectively) than CC. The BFR/BS was more than two times greater in LE (p=0.019) and LC (p=0.074) than CC. The PGE2 levels were elevated at 8days post-osteotomy in all groups and the treatment groups remained elevated compared to the CC group on days 15, 19 and 23. The data suggest that combined exposure to big ET1 and mechanical loading results in increased osteogenesis as measured in biomechanical, histomorphometric and biochemical responses.

A Comparison of Collagen Crosslink Content in Bone Specimens from Elective Total Hip Arthroplasty Patients with and without Type 2 Diabetes

Objective: To compare the amount of non-enzymatic and enzymatic collagen crosslinks in bone specimens from total hip replacement patients with and without type 2 diabetes (controls). Methods: This ex vivo cross-sectional study included 34 bone specimens (13 from patients with type 2 diabetes, 21 from controls) from men and women ≥ 65 years. All participants were undergoing an elective total hip replacement due to osteoarthritis. Cancellers cores were extracted from the interior of the femoral neck/head and bone cores were reduced to approximately 50 mg of powder. High performance liquid chromatography (HPLC) was used to quantify pentosidine, pyridinoline (PYD) and deoxypyridoline (DPD), which were normalized to collagen content. The mean (SD) was calculated for continuous variables and an independent Student’s t-test was used to compare crosslink content between groups. Results: 13 specimens were collected from participants with type 2 diabetes (mean [SD] age 73.8 [6.2] years) and 21 specimens were collected from controls (mean [SD] age 76.7 [6.8] years, p=0.222). There was no between-group difference in the amount of bone pentosidine (type 2 diabetes: 2.07 [0.94] mmol/mol collagen vs. control: 1.99 [0.60] mmol/mol collagen, p=0.753), PYD (type 2 diabetes: 219.2 [25.3] mmol/mol collagen vs. control: 208.1 [25.8] mmol/mol collagen, p=0.227) or DPD (type 2 diabetes: 132.3 [25.9] mmol/mol collagen vs. control: 130.0 [22.8] mmol/mol collagen, p=0.787). Conclusion: Elective total hip replacement patients with and without type 2 diabetes have similar collagen crosslink profiles. Future studies should consider potential confounding factors, such as bone turnover rate, which may influence collagen crosslink content.

POSTERIOR MAXILLARY SOCKET PRESERVATION USING COLLAGENATED CORTICO-CANCELLOUS XENOGRAFT

The current study was conducted to evaluate posterior maxillary socket preservation using Prehydrated Collagenated Cortico-Cancellous Equine Xenograft (Osteobiol®) compared to normal socket healing. 22 posterior maxillary extraction sites, indicated for socket preservation and implant placement were included in this study. They were randomly divided into two equal groups; 1-Study group: in which the extraction socket was filled with the bone graft. 2-Control group: in which the extraction socket was left to heal without bone grafting. All patients underwent preoperative evaluation, the target tooth was extracted atraumatically and the alveolar ridge was preserved using Osteobiol Putty bone graft material in the study group cases. All patients underwent follow up for 9 months. During this period they were regularly examined clinically to monitor healing and assess for any complications. Nine months after the first operative phase, bone core biopsy was taken from all cases of both groups, followed by implant placement. Histologic and histomorphometric evaluation of the retrieved biopsies was performed to assess for the amount, type, percentage of new bone formation as well as the osteoblastic/osteoclastic ratio. No major intraoperative or postoperative clinical complications were encountered in both groups. Histologic and histomorphometric examination of the bone biopsies revealed new bone formation in both groups. Morphometric analysis showed that the mean area fraction of the total bone matrix and the lamellar bone area fraction were significantly higher in the study group than the control group. The osteoblastic/osteoclastic ratio was significantly higher in the study group than in the control group. The used grafting material could be successfully utilized for socket preservation in posterior maxilla with minimally invasive procedures without the use of a barrier membrane or a mucoperiosteal flap.

Minimally Invasive Alveolar Ridge Preservation Utilizing an In Situ Hardening β-Tricalcium Phosphate Bone Substitute: A Multicenter Case Series.

Ridge preservation measures, which include the filling of extraction sockets with bone substitutes, have been shown to reduce ridge resorption, while methods that do not require primary soft tissue closure minimize patient morbidity and decrease surgical time and cost. In a case series of 10 patients requiring single extraction, in situ hardening beta-tricalcium phosphate (β-TCP) granules coated with poly(lactic-co-glycolic acid) (PLGA) were utilized as a grafting material that does not necessitate primary wound closure. After 4 months, clinical observations revealed excellent soft tissue healing without loss of attached gingiva in all cases. At reentry for implant placement, bone core biopsies were obtained and primary implant stability was measured by final seating torque and resonance frequency analysis. Histological and histomorphometrical analysis revealed pronounced bone regeneration (24.4 ± 7.9% new bone) in parallel to the resorption of the grafting material (12.9 ± 7.7% graft material) while high levels of primary implant stability were recorded. Within the limits of this case series, the results suggest that β-TCP coated with polylactide can support new bone formation at postextraction sockets, while the properties of the material improve the handling and produce a stable and porous bone substitute scaffold in situ, facilitating the application of noninvasive surgical techniques.

Three-Dimensional Bone Regeneration of Alveolar Ridge Defects Using Corticocancellous Allogeneic Block Grafts: Histologic and Immunohistochemical Analysis.

In this study, the effectiveness of a corticocancellous block allograft for restoring alveolar ridge defects in preparation for the placement of dental implants was assessed. Significant ridge defects in four partially edentulous patients were reconstructed using an irradiated corticocancellous allogeneic block soaked in platelet-rich plasma, which was also covered with a resorbable collagen membrane. After 5 or 6 months, the sites were reentered and a trephine bone core specimen was obtained from each augmented site for histologic, histomorphometric, and immunohistochemical assessment. In all four cases, histologic evaluation of the augmented site showed areas of new vital bone formation around the graft material (mean newly formed bone fraction, 23.7%; mean total mineralized tissue fraction, 40.1%), in which osteocytes were frequently observed within the lacunae. Immunohistochemical analysis showed the presence of biomarkers commonly related to active bone formation (alkaline phosphatase, osteocalcin, and bone morphogenetic protein-2), confirming that the biochemical environment was conducive to new bone formation. The findings of this study demonstrate that the use of allogeneic block grafts for restoring alveolar ridge defects prior to the placement of dental implants may be an effective and advantageous alternative to autograft procedures.

Efficacy of a new porous titanium compression screw using an ovine osseointegration model

Event Abstract Back to Event Efficacy of a new porous titanium compression screw using an ovine osseointegration model Robert A. Poggie1, Louis-Philippe Lefebvre2, Stephanie Grenier2, Madeleine Chagnon3 and Michel Assad3 1 BioVera Inc., Canada 2 National Research Council Canada, Medical Devices, Canada 3 AccelLAB Inc., Orthopedics and Biomaterials, Canada Introduction: Fracture fixation of small bones remains challenging for pathologies relating to tenuous retrograde blood supply. For example, acute scaphoid fractures are among the most common traumatic injuries and account for 50-80% of carpal injuries[1]. Solid screws without bone grafting are often ineffective in cases of osteonecrosis. The objectives of this study were to evaluate bone healing and strength of fixation of a new porous titanium (Ti) compression screw compared to a conventional titanium compression screw in cortical bone and in challenging models of gap-healing and osteonecrosis. Materials and Methods: Six (6) female Dorset sheep (>18mo.; 75-90kg) were prepared for bilateral hind limb surgeries using either porous Ti (NRC) or conventional solid Ti (Acutrak) headless cannulated compression screws (Ø=3.3-3.8mm; L=15mm). Porous titanium screws presented a 40% porosity with a mean pore size of 344µm, and compressive, shear, and tensile strengths of 157 MPa, 113 MPa and 77 MPa, respectively. The 1st model evaluated non-union following removal of a bone core (Ø=8mm; L=8mm) from the proximal tibia and screw placement in its middle, resulting in a 2-mm peripheral gap. The 2nd model simulated osteonecrosis with a 2nd core removal (Ø=14mm; L=8mm) from the distal femur, submersion in liquid N2, and screw fixation of the devitalized core. The 3rd model quantified bone ingrowth and torsional strength at mid-diaphyseal tibial cortical locations. Sheep were then euthanized at 6 and 12 weeks post-implantation. Bone ingrowth was reconstructed by Micro-CT (SkyScan 1172) and quantified with histomorphometry. Explanted screws were sectioned longitudinally, processed for undecalcified histology, infiltrated with PMMA, microground (Exakt 400 CS), and stained with Goldner’s Trichrome. Digital images were analyzed for bone-implant contact and volumetric bone ingrowth. Torsional strength was recorded with a continuous digital torque meter at necropsy. Results: Following 6 weeks of implantation in the non-union model, 75% of new bone formed adjacent to porous Ti as opposed to 38% with solid Ti screws. At 12 weeks, porous Ti screws exhibited 89% new bone formation vs. 79% for controls. Below the actual gap, bone filled 99% of the area within threads in porous Ti implants vs. 83% for controls at 12 weeks. Following bone devitalization, porous Ti showed up to 51% of new bone formation within its cannulated center as opposed to ≤3% for conventional screws. For the bone ingrowth model (Figure 1), linear bone apposition reached 55% for porous Ti vs. 36% (controls). Limited by failure of the Allen driver, the maximum torque for porous screws was 0.78Nm vs. 0.42Nm for controls. Histopathology revealed excellent safety and biocompatibility as evidenced by a mild tissue reaction. Discussion: Superior bone apposition, volumetric bone ingrowth and torsional strength were observed using the porous titanium screw, likely attributed to its interconnected porosity and higher surface area. A beneficial bone conduction effect was pronounced within the screw cannula. The clinical implication is that porous Ti does not occlude bone ingrowth and vascularization is observed within the compression device itself, translating into bone fixation and healing. Conclusion: Internal fixation with porous titanium compression screws increases the fixation strength and the potential for bone ingrowth in clinically challenging conditions of non-union and osteonecrosis. The authors would like to sincerely thank Dr. Paul A. Martineau and Dr. Edward J. Harvey (McGill University Health Centre), who co-developed this porous implant with the National Research Council of Canada; Special thanks to Dr. Cathy Tkaczyk and Mr. Yannick Trudel for their respective scientific and highly-skilled surgical support

Micro-CT in the Assessment of Pediatric Renal Osteodystrophy by Bone Histomorphometry.

Computed tomography (CT) measurements can distinguish between cortical and trabecular bone density in vivo. High-resolution CTs assess both bone volume and density in the same compartment, thus potentially yielding information regarding bone mineralization as well. The relationship between bone histomorphometric parameters of skeletal mineralization and bone density from microcomputed tomography (μCT) measurements of bone cores from patients on dialysis has not been assessed. Bone cores from 68 patients with ESRD (age =13.9±0.5 years old; 50% men) and 14 controls (age =15.3±3.8 years old; 50% men) obtained as part of research protocols between 1983 and 2006 were analyzed by bone histomorphometry and μCT. Bone histomorphometric diagnoses in the patients were normal to high bone turnover in 76%, adynamic bone in 13%, and osteomalacia in 11%. Bone formation rate did not correlate with any μCT determinations. Bone volume measurements were highly correlated between bone histomorphometry and μCT (bone volume/tissue volume between the two techniques: r=0.70; P<0.001, trabecular thickness and trabecular separation: r=0.71; P<0.001, and r=0.56; P<0.001, respectively). Osteoid accumulation as determined by bone histomorphometry correlated inversely with bone mineral density as assessed by μCT (osteoid thickness: r=-0.32; P=0.01 and osteoid volume: r=-0.28; P=0.05). By multivariable analysis, the combination of bone mineral density and bone volume (as assessed by μCT) along with parathyroid hormone and calcium levels accounted for 38% of the variability in osteoid volume (by histomorphometry). Measures of bone volume can be accurately assessed with μCT. Bone mineral density is lower in patients with excessive osteoid accumulation and higher in patients with adynamic, well mineralized bone. Thus, bone mineralization may be accurately assessed by μCT of bone biopsy cores. Additional studies are warranted to define the value of high-resolution CT in the prediction of bone mineralization in vivo.

Drug diffusion, integration, and stability of nanoengineered drug-releasing implants in bone ex-vivo.

To treat skeletal conditions such as bone infections, osteoporotic fractures, and osteosarcoma, it would be ideal to introduce drugs directly to the affected site. Localized drug delivery from the bone implants is a promising alternative to systemic drug administration. In this study we investigated electrochemically nanoengineered Ti wire implants with titania nanotubes (TNTs), as minimally invasive drug-releasing implants for the delivery of drugs directly into the bone tissue. Since trabecular bone in vivo contains a highly interconnected bone marrow, we sought to determine the influence of marrow on drug release and diffusion. Electrochemical anodization of Ti wires (length 10 mm) was performed to create an oxide layer with TNTs on the surface, followed by loading with a fluorescent model drug, Rhodamine B (RhB). Cores of bovine trabecular bone were generated from the sternum of a young steer, and were processed to have an intact bone marrow, or the marrow was removed. RhB-loaded TNTs/Ti wires were inserted into the bone cores, which were then cultured ex vivo using the ZetOS™ bioreactor system to maintain bone viability. Release and diffusion of RhB inside the bone was monitored using fluorescence imaging and different patterns of drug transport in the presence or absence of marrow were observed. Scanning electron microscopy of the implants after retrieval from bone cores confirmed survival of the TNTs structures. Histological investigation showed the presence of bone cells adherent on the implants. This study shows a potential of Ti drug-releasing implants based on TNTs technology towards localized bone therapy. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 714-725, 2016.

MG-122 Atypical fish pattern consistent with insertion of 5’ CBFB into 16p13 in a case of therapy-related acute myeloid leukaemia

Background The inv (16) and related t (16;16) resulting in fusion of CBFB gene (16q22) to MYH11 (16p13) are not commonly observed in therapy-related AML (t-AML). Objective To present a case of t-AML with CBFB/MYH11 fusion and rearrangement of chromosome 16 other than the commonly described inv (16) and related t (16;16). Case report A 46-year-old woman presented with t-AML 1.25 years after adjuvant radiation and chemotherapy for rectal carcinoma. Peripheral blood showed marked reduction in neutrophils, 24% blasts and increased lymphocytes and monocytes. Bone marrow aspirates revealed large blasts with abundant cytoplasm, fine nuclear chromatin, occasional deep nuclear folds and prominent nucleoli. Bone core biopsy mainly consisted of blasts and was remarkable for numerous eosinophilic myelocytes and metamyelocytes. Cytogenetic analysis of bone marrow aspirate was interpreted as 46,XX,inv (16)(p13.3q22)[6]/47,idem,+8[14]/48,idem,+6,+8[2]. Interphase FISH analysis using the CBFB break-apart probe showed an atypical abnormal signal pattern of two CBFB fusion signals and one 5’ CBFB probe signal. Metaphase FISH analysis showed an abnormal chromosome 16 with a CBFB fusion signal on one arm and a 5’ CBFB signal on the other arm. The normal 16 homologue showed the expected one CBFB fusion signal. The CBFB/MYH11 fusion transcript type A was detected by RT-PCR. Conclusion The abnormal CBFB pattern observed in this case differs from what is expected for an inv (16) or t (16:16), but can be explained by an insertion of 5’ CBFB into 16p13. This case demonstrates that insertion of 5’ CBFB into 16p13 is another mechanism of producing a CBFB /MYH11 fusion.

Fluoroscopy-Guided Percutaneous Vertebral Body Biopsy Using a Novel Drill-Powered Device: Technical Case Series.

A novel coaxial biopsy system powered by a handheld drill has recently been introduced for percutaneous bone biopsy. This technical note describes our initial experience performing fluoroscopy-guided vertebral body biopsies with this system, compares the yield of drill-assisted biopsy specimens with those obtained using a manual technique, and assesses the histologic adequacy of specimens obtained with drill assistance. Medical records of all single-level, fluoroscopy-guided vertebral body biopsies were reviewed. Procedural complications were documented according to the Society of Interventional Radiology classification. The total length of bone core obtained from drill-assisted biopsies was compared with that of matched manual biopsies. Pathology reports were reviewed to determine the histologic adequacy of specimens obtained with drill assistance. Twenty eight drill-assisted percutaneous vertebral body biopsies met study inclusion criteria. No acute complications were reported. Of the 86% (24/28) of patients with clinical follow-up, no delayed complications were reported (median follow-up, 28weeks; range 5-115weeks). The median total length of bone core obtained from drill-assisted biopsies was 28mm (range 8-120mm). This was longer than that obtained from manual biopsies (median, 20mm; range 5-45mm; P=0.03). Crush artifact was present in 11% (3/28) of drill-assisted biopsy specimens, which in one case (3.6%; 1/28) precluded definitive diagnosis. A drill-assisted, coaxial biopsy system can be used to safely obtain vertebral body core specimens under fluoroscopic guidance. The higher bone core yield obtained with drill assistance may be offset by the presence of crush artifact.

3D Porous Architecture of Stacks of β-TCP Granules Compared with That of Trabecular Bone: A microCT, Vector Analysis, and Compression Study.

The 3D arrangement of porous granular biomaterials usable to fill bone defects has received little study. Granular biomaterials occupy 3D space when packed together in a manner that creates a porosity suitable for the invasion of vascular and bone cells. Granules of beta-tricalcium phosphate (β-TCP) were prepared with either 12.5 or 25 g of β-TCP powder in the same volume of slurry. When the granules were placed in a test tube, this produced 3D stacks with a high (HP) or low porosity (LP), respectively. Stacks of granules mimic the filling of a bone defect by a surgeon. The aim of this study was to compare the porosity of stacks of β-TCP granules with that of cores of trabecular bone. Biomechanical compression tests were done on the granules stacks. Bone cylinders were prepared from calf tibia plateau, constituted high-density (HD) blocks. Low-density (LD) blocks were harvested from aged cadaver tibias. Microcomputed tomography was used on the β-TCP granule stacks and the trabecular bone cores to determine porosity and specific surface. A vector-projection algorithm was used to image porosity employing a frontal plane image, which was constructed line by line from all images of a microCT stack. Stacks of HP granules had porosity (75.3 ± 0.4%) and fractal lacunarity (0.043 ± 0.007) intermediate between that of HD (respectively 69.1 ± 6.4%, p < 0.05 and 0.087 ± 0.045, p < 0.05) and LD bones (respectively 88.8 ± 1.57% and 0.037 ± 0.014), but exhibited a higher surface density (5.56 ± 0.11 mm2/mm3 vs. 2.06 ± 0.26 for LD, p < 0.05). LP granular arrangements created large pores coexisting with dense areas of material. Frontal plane analysis evidenced a more regular arrangement of β-TCP granules than bone trabecule. Stacks of HP granules represent a scaffold that resembles trabecular bone in its porous microarchitecture.

HER2 FISH analysis on a skeletal metastasis: a case report and technical review

Eighty per cent of patients who develop metastatic breast cancer will experience a skeletal metastasis. National guidelines recommend biopsy and repeat estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) testing for all metastatic breast cancers to guide further treatment planning. Biomarker analysis in bone biopsy samples is challenging due to the necessity of decalcification of the bone sample in order to allow tissue sectioning. The decalcification solutions may result in the degradation of proteins and thus affect the results of immunohistochemical (IHC) testing for ER, PR, and HER2. The decalcification solutions may also degrade nucleic acids, and result in poor or no hybridization signals when attempting in situ hybridization (ISH) testing for HER2. Here, we report a patient with metastatic breast cancer to the bone who underwent image guided core needle biopsy. Her past medical history was significant for ER+, PR+, and HER2+ breast cancer. The biopsy yielded cores of bone, which were decalcified, and a blood clot that was separated from the bone and fixed in formalin without decalcification. Both specimens showed metastatic carcinoma consistent with a breast primary when viewing hematoxylin and eosin (H&E) stained sections. Immunohistochemical analysis, which was performed only on the clot sections, showed ER+, PR − , and HER2 equivocal (2+) tumor cells. Immunohistochemical analysis was not performed on the bony tissue, because our assays are not validated for use on decalcified tissue. Human epidermal growth factor receptor-2 fluorescence in situ hybridization (FISH) analysis was attempted on the bone biopsy and yielded no signals (analytic failure). This is typical of HER2 FISH analysis in decalcified specimens, due to the impaired deoxyribonucleic acid (DNA) quality. However, HER2 FISH analysis on the clot sections showed that the HER2 gene was amplified. Given the clinical importance of repeat HER2 testing in patients with recurrent breast cancer, techniques that avoid decalcification are needed. Separating the blood clot from the bony tissue, and processing it without decalcification may yield viable tumor whose DNA has not been degraded, and it then can be used for the analysis of ER, PR, and HER2.

Application of xenograft for alveolar ridge preservation in posterior sites: a randomized controlled clinical trial

To investigate the effect of ridge preservation with Bio-Oss Collagen and Bio-Gide in posterior sites. From May 2010 to July 2013, 16 patients with bilateral posterior teeth planned to be extracted and replaced by implants were enrolled. One of the sockets was randomly selected and presserved with Bio-Oss Collagen and Bio-Gide (intervention group). The contralateral socket was left to heal spontaneously (control group). Cone-beam (CBCT) scans were performed immediately after the extraction and 6 month later. The bone cores were collected during the implant placement surgery and analyzed by micro-computed tomography. After 6 month healing, the vertical and horizontal dimensional alteration of the treatment group were (0.55 ± 1.05) mm and (-0.99 ± 0.94) mm respectively, while the vertical and horizontal change of control group were (-0.71 ± 1.41) mm and (-2.26 ± 1.29) mm respectively. The micro-computed tomography results showed that there was no significant difference in new bone volume between control and intervention groups. Applying Bio-Oss Collagen and Bio-Gide for ridge preservation in posterior sites resulted in less vertical and horizontal bone resorption of sockets following extraction.

Validation of single photon absorptiometry for on-farm measurement of density and mineral content of tail bone in cattle

A validation study examined the accuracy of a purpose-built single photon absorptiometry (SPA) instrument for making on-farm in vivo measurements of bone mineral density (BMD) in tail bones of cattle. In vivo measurements were made at the proximal end of the ninth coccygeal vertebra (Cy9) in steers of two age groups (each n = 10) in adequate or low phosphorus status. The tails of the steers were then resected and the BMD of the Cy9 bone was measured in the laboratory with SPA on the resected tails and then with established laboratory procedures on defleshed bone. Specific gravity and ash density were measured on the isolated Cy9 vertebrae and on 5-mm2 dorso-ventral cores of bone cut from each defleshed Cy9. Calculated BMD determined by SPA required a measure of tail bone thickness and this was estimated as a fraction of total tail thickness. Actual tail bone thickness was also measured on the isolated Cy9 vertebrae. The accuracy of measurement of BMD by SPA was evaluated by comparison with the ash density of the bone cores measured in the laboratory. In vivo SPA measurements of BMD were closely correlated with laboratory measurements of core ash density (r = 0.92). Ash density and specific gravity of cores, and all SPA measures of BMD, were affected by phosphorus status of the steers, but the effect of steer age was only significant (P &lt; 0.05) for steers in adequate phosphorus status. The accuracy of SPA to determine BMD of tail bone may be improved by reducing error associated with in vivo estimation of tail bone thickness, and also by adjusting for displacement of soft tissue by bone mineral. In conclusion a purpose-built SPA instrument could be used to make on-farm sequential non-invasive in vivo measurements of the BMD of tailbone in cattle with accuracy acceptable for many animal studies.

Human breast cancer bone metastasis in vitro and in vivo: a novel 3D model system for studies of tumour cell-bone cell interactions.

Bone is established as the preferred site of breast cancer metastasis. However, the precise mechanisms responsible for this preference remain unidentified. In order to improve outcome for patients with advanced breast cancer and skeletal involvement, we need to better understand how this process is initiated and regulated. As bone metastasis cannot be easily studied in patients, researchers have to date mainly relied on in vivo xenograft models. A major limitation of these is that they do not contain a human bone microenvironment, increasingly considered to be an important component of metastases. In order to address this shortcoming, we have developed a novel humanised bone model, where 1 × 10(5) luciferase-expressing MDA-MB-231 or T47D human breast tumour cells are seeded on viable human subchaodral bone discs in vitro. These discs contain functional osteoclasts 2-weeks after in vitro culture and positive staining for calcine 1-week after culture demonstrating active bone resorption/formation. In vitro inoculation of MDA-MB-231 or T47D cells colonised human bone cores and remained viable for <4 weeks, however, use of matrigel to enhance adhesion or a moving platform to increase diffusion of nutrients provided no additional advantage. Following colonisation by the tumour cells, bone discs pre-seeded with MDA-MB-231 cells were implanted subcutaneously into NOD SCID mice, and tumour growth monitored using in vivo imaging for up to 6 weeks. Tumour growth progressed in human bone discs in 80 % of the animals mimicking the later stages of human bone metastasis. Immunohistochemical and PCR analysis revealed that growing MDA-MB-231 cells in human bone resulted in these cells acquiring a molecular phenotype previously associated with breast cancer bone metastases. MDA-MB-231 cells grown in human bone discs showed increased expression of IL-1B, HRAS and MMP9 and decreased expression of S100A4, whereas, DKK2 and FN1 were unaltered compared with the same cells grown in mammary fat pads of mice not implanted with human bone discs.