OBJECTIVE: To investigate the biocompatibility of porous WE43 magnesium alloy scaffolds manufactured by 3D printing technology and to observe its effect in treating femoral defects in New Zealand white rabbits. METHODS: In vitro cytotoxicity test was performed using bone marrow mesenchymal stem cells from Sprague Dawley (S-D) rats. According to the different culture media, the cells were divided into 100% extract group, 50% extract group, 10% extract group and control group. After culturing for 1, 3 and 7 days, the cell activity of each group was determined by cell counting kit-8 (CCK-8). In the in vivo experiment, 3.0-3.5 kg New Zealand white rabbits were randomly divided into three groups: Experimental group, bone cement group and blank group, with 9 rabbits in each group. Each rabbit underwent surgery on the left lateral femoral condyle, and a bone defect with a diameter of 5 mm and a depth of 6 mm was created using a bone drill. The experimental group was implanted with WE43 magnesium alloy scaffolds, the bone cement group was implanted with calcium sulfate bone cement, and the blank group was not implanted. Then 4, 8 and 12 weeks after surgery, 3 rabbits in each group were euthanized by carbon dioxide anesthesia, and the femur and important internal organs were sampled. Micro-computed tomography (Micro-CT) scanning was performed on the left lateral femoral condyle. Sections of important internal organs were prepared and stained with hematoxylin-eosin (HE). Hard tissue sections were made from the left lateral femoral condyle and stained with methylene blue acid fuchsin and observed under a microscope. RESULTS: In the cytotoxicity test, the cell survival rate in the 100% extract group was higher than that in the control group (140.56% vs. 100.00%, P < 0.05) on 1 day of culture; there was no statistically significant difference (P>0.05) in cell survival rate among the groups on 3 days of culture; the cell survival rate in the 100% extract group was lower than that in the control group (68.64% vs. 100.00%, P < 0.05) on 7 days of culture. Micro-CT scanning in the in vivo experiment found that most of the scaffolds in the experimental group had been degraded in 4 weeks, with very few high-density scaffolds remaining. In 12 weeks, there was no obvious stent outline. In 4 weeks, a certain amount of gas was generated around the WE43 magnesium alloy scaffold, and the gas was significantly reduced from 8 to 12 weeks. Hard tissue sections showed that a certain amount of extracellular matrix and osteoid were generated around the scaffolds in the experimental group in 4 weeks. In the bone cement group, most of the calcium sulfate bone cement had been degraded. In 8 weeks, the osteoid around the scaffold and its degradation products in the experimental group increased significantly. In 12 weeks, new bone was in contact with the scaffold around the scaffold in the experimental group. There was less new bone in the bone cement group and the blank group. CONCLUSION The porous WE43 magnesium alloy scaffold fabricated by 3D printing process has good biocompatibility and good osteogenic properties, and has the potential to become a new material for repairing bone defects.
Animals ; Rabbits ; Printing, Three-Dimensional ; Alloys/chemistry* ; Tissue Scaffolds/chemistry* ; Magnesium/chemistry* ; Rats, Sprague-Dawley ; Biocompatible Materials ; Mesenchymal Stem Cells/cytology* ; Femur/surgery* ; Rats ; Absorbable Implants ; Male ; Bone Regeneration ; Tissue Engineering/methods* ; Cells, Cultured

Aged ; Biological Monitoring ; Female ; Femur/chemistry* ; Humans ; Knee Joint/chemistry* ; Male ; Meniscus/chemistry* ; Metals/analysis* ; Middle Aged ; Tibia/chemistry*

The present study aimed at investigating the effects of Puerarin (PR), a major isoflavonoid isolated from the Chinese medicinal herb Puerariae radix, on bone metabolism and the underlying mechanism of action. The in vivo assay, female mice were ovariectomized (OVX), and the OVX mice were fed with a diet containing low, middle, and high doses of PR (2, 4, and 8 mg·d(-1), respectively) or 17β-estradiol (E2, 0.03 μg·d(-1)) for 4 weeks. In OVX mice, the uterine weight declined, and intake of PR at any dose did not affect uterine weight, compared with the control. The total femoral bone mineral density (BMD) was significantly reduced by OVX, which was reversed by intake of the diet with PR at any dose, especially at the low dose. In the in vitro assay, RAW264.7 cells were used for studying the direct effect of PR on the formation of osteoclasts. PR reduced the formation of tartrate resistant acid phosphatase (TRAP)-positive multi-nucleated cells in the RAW 264.7 cells induced by receptor activator for nuclear factor-κB Ligand (RANKL). MC3T3-E1 cells were used for studying the effects of PR on the expression of osteoprotegerin (OPG) and RANKL mRNA expression in osteoblasts. The expression of OPG mRNA and RANKL mRNA was detected by RT-PCR on Days of 5, 7, 10, and 12 after PR exposure. PR time-dependently enhanced the expression of OPG mRNA and reduced the expression of RANKL mRNA in MC3T3-E1 cells. In conclusion, our results suggest that PR can effectively prevent bone loss in OVX mice without any hyperplastic effect on the uterus, and the antiosteoporosis activity of PR may be related to its effects on the formation of osteoclasts and the expression of RANKL OPG in osteoblasts.
Animals ; Bone Density ; drug effects ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Femur ; chemistry ; growth & development ; metabolism ; Humans ; Isoflavones ; administration & dosage ; Mice ; Osteoclasts ; drug effects ; metabolism ; Osteoporosis ; genetics ; metabolism ; physiopathology ; prevention & control ; Osteoprotegerin ; genetics ; metabolism ; Ovariectomy ; Pueraria ; chemistry ; RANK Ligand ; genetics ; metabolism

OBJECTIVETo study the bone state with ultimate stress by examining biomechanical distribution of upper femur in Chinese, in order to accumulate more experiences for clinical work.

METHODSTotally 60 Chinese femurs from fresh cadavers were randomly divided into two groups. All the femurs were cleaned, and the body age ranged from 36 to 72 years old, averaged 56.4 years, including 41 from males, and 19 from females. These two groups underwent mechanical stress and bending stress tests. Special mechanical laboratory and machines were used to get the information. Results about the loading value at each testing point under stress were collected.

RESULTSThe four faces of the upper femur suffered different stress under external forces. The bone on upper femur can tolerate more mechanical stress than bending stress. Medial and lateral region of the femur neck and the rear side of the small tuberosity section were themain position enduring the vertical stress. The rear position of the base femur neck and the small tuberosity section were the main regions enduring the bending stress. Those main positions had strong cancellous bones. The intertrochanteric fracture fixation and artificial femoral stems were designed depending on this biomechanical basis.

CONCLUSIONAccording to our experiment result, doctors need to chose more effective fixations for upper femur fracture, and femoral stems for the patients. More information should be collected by further researches.

Adult ; Aged ; Biomechanical Phenomena ; Female ; Femur ; chemistry ; Humans ; Male ; Middle Aged ; Stress, Mechanical

Silicosis had been considered for decades as an illness with manifestations of lung fibrosis due to inhalation of overconcentrated SiO2 dust. To the best of our knowledge, studies have yet to report SiO2 deposits in any other tissues and organs. In the present case, while performing bilateral artificial total hip arthroplasty for one patient, we found that the articular cartilage of the bilateral femoral head was black. Therefore, specimens thereof were sent for pathological examination. Pathological examination (immunohistochemistry) and polarized light microscopy revealed the presence of considerable brown, acicular, rhombic, and crumb-like crystals. The crystals were mainly composed of SiO2. SiO2 could deposit in vessels and femoral head cartilage via blood circulation.
Blood Vessels/*chemistry ; Cartilage/*chemistry ; Femur Head/*pathology ; Humans ; Lung/*radiography ; Male ; Middle Aged ; Silicon Dioxide/*analysis ; Silicosis/*diagnosis ; Synovitis/*pathology

OBJECTIVETo explore the effect of combination of Epimedii Folium and Ligustri Lucidi Fructus on osteoporosis rats induced by retinoic acid.

METHODSixty three-month-old male Wistar rats were randomly divided into the normal control group, the model group, the Epimedii Folium group, the Ligustri Lucidi Fructus group, the combination group of Epimedii Folium and Ligustri Lucidi Fructus and the raloxifene group. The osteoporosis model was established through oral administration with retinoic acid for two weeks. Meanwhile, all of treatment groups were administered with corresponding drugs for three weeks. The contents of serum calcium (Ca), phosphorus (P), alkaline phosphatase (AKP) and tartrate-resistant acid phosphatase (StrACP) were detected, and the pathomorphological changes of femurs were observed.

RESULTThe model control group showed much lower contents of serum Ca and P than the normal control group, but with significantly higher AKP and StrACP activity than the normal control group. The femoral head area showed reduced, narrow and sparse trabecular bones, with typical osteoporosis-like changes. Compared with the model control group, all of treated groups showed significant increase in Ca and P contents in serum, and down-regulate AKP and StrACP levels, while trabecular bones became more and wider, and densely interweaved as a reticular formation. Among them, the combination group showed the most significant effect.

CONCLUSIONEpimedii Folium and Ligustri Lucidi Fructus could effectively correct the abnormal bone metabolism and improve pathological conditions of bone tissues, so as to show the anti-osteoporosis effect. The combined application of the two drugs showed a better efficacy.

Acid Phosphatase ; blood ; Alkaline Phosphatase ; blood ; Animals ; Body Weight ; drug effects ; Calcium ; blood ; Drug Interactions ; Drugs, Chinese Herbal ; pharmacology ; therapeutic use ; Epimedium ; chemistry ; Femur ; drug effects ; pathology ; Isoenzymes ; blood ; Ligustrum ; chemistry ; Male ; Osteoporosis ; blood ; chemically induced ; drug therapy ; pathology ; Phosphorus ; blood ; Rats ; Rats, Wistar ; Tartrate-Resistant Acid Phosphatase ; Tretinoin ; adverse effects

Bone mineral density (BMD) using dual energy radiography absorptiometry are commonly used for the diagnosis of osteoporosis. It is usually measured at the spine and also at one hip joint. Controversy still exists regarding the use of bilateral hip scanning. We analyzed the difference of BMD at bilateral hips in 384 postmenopausal women, retrospectively. The concordance and discordance rates of the lowest T-score and BMD between both hips were evaluated. The BMDs of the femoral neck and trochanter were significantly different between both hips (P < 0.05). There were also discrepancies between the lowest T-scores of both hips (P < 0.05). The discordance rates were about 30%. Due to significant differences in BMD between both hips at the femoral neck and trochanter and high discordance rate, bilateral hip measurements using DEXA are recommended to avoid underestimating osteoporosis.
Absorptiometry, Photon ; Aged ; Body Mass Index ; *Bone Density ; Female ; Femur/chemistry ; Femur Neck/chemistry ; Hip/*radiography ; Humans ; Middle Aged ; Osteoporosis/diagnosis ; Postmenopause ; Retrospective Studies

BACKGROUNDCalcium phosphate cement (CPC) is a favorable bone-graft substitute, with excellent biocompatibility and osteoconductivity. However, its reduced osteoinductive ability may limit the utility of CPC. To increase its osteoinductive potential, this study aimed to prepare tissue-engineered CPC and evaluate its use in the repair of bone defects. The fate of transplanted seed cells in vivo was observed at the same time.

METHODSTissue-engineered CPC was prepared by seeding CPC with encapsulated bone mesenchymal stem cells (BMSCs) expressing recombinant human bone morphogenetic protein-2 (rhBMP-2) and green fluorescent protein (GFP). Tissue-engineered CPC and pure CPC were implanted into rabbit femoral condyle bone defects respectively. Twelve weeks later, radiographs, morphological observations, histomorphometrical evaluations, and in vivo tracing were performed.

RESULTSThe radiographs revealed better absorption and faster new bone formation for tissue-engineered CPC than pure CPC. Morphological and histomorphometrical evaluations indicated that tissue-engineered CPC separated into numerous small blocks, with active absorption and reconstruction noted, whereas the residual CPC area was larger in the group treated with pure CPC. In the tissue-engineered CPC group, in vivo tracing revealed numerous cells expressing both GFP and rhBMP-2 that were distributed in the medullar cavity and on the surface of bony trabeculae.

CONCLUSIONTissue-engineered CPC can effectively repair bone defects, with allogenic seeded cells able to grow and differentiate in vivo after transplantation.

Animals ; Bone Cements ; chemistry ; Bone Morphogenetic Protein 2 ; Calcium Phosphates ; chemistry ; Cells, Cultured ; Femur ; surgery ; Rabbits ; Recombinant Proteins ; Tissue Engineering ; methods ; Transforming Growth Factor beta

OBJECTIVETo determine the concentrations of lead (Pb) and cadmium (Cd) in three kinds of materials (cartilage, cortical bone, and cancellous bone) of the femur head obtained from patients in the process of operation.

METHODSConcentrations of Pb and Cd were determined in selected parts of the femur head of 30 patients after total hip arthroplasty, using ICP-AES (atomic absorption spectrophotometry).

RESULTSPb contained the highest concentration in cortical bone, while Cd did so in cancellous bone. There were statistically significant differences in the concentrations of both elements between the cartilage and cortical bone, and also differences in the concentration of Pb between the cartilage and cancellous bone. There were no significant differences in the concentrations of Pb or Cd between cortical and cancellous bone.

CONCLUSIONComparative studies on toxic metals should take into account both analogous bones and their fragments, as even if they come from the same kind of bones (e.g. femur head), clear differences exist in concentrations of heavy metals related to the sampling site and type of tissue (cartilage, cortical bone, and cancellous bone).

Adult ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Hip ; Cadmium ; chemistry ; Environmental Exposure ; Environmental Pollutants ; chemistry ; Female ; Femur Head ; chemistry ; Humans ; Lead ; chemistry ; Middle Aged ; Poland

Referring to the anatomical characterization of natural spongy bone and channel network in cortical bone, we designed a new pattern of biomimetic impalnt with preset channel for blood vessel inserting to treat early femoral head necrosis. The surgical ptrocedure was simulated by CAD model. Ceramic stereolithography was applied to fabricate the green part. Other process, such as dehydration, rinsing, drying and sintering, were taken successively. The final ceramic part kept identical with the engineered part either in the shape or in the internal structure. No deformation or crack happened. Pore size, interconnected pore size, porosity and interconnected porosity of ceramic part could satisfy cellular grouth. Spectrum analysis showed that no phase transition or chemical reaction happened during fabrication process. The biocompatibility of the final part kept the same with original during beta-TCP powder. The compressive strength was 23.54 MPa, close to natural spongy bone. It is an ideal implant to treat early femoral head necroseis because it makes preimplantation of cells and biological factors, blood velssel inserting, early establishment of blood supply possible. At the same time, it could provide enough mechanical support to prevent collapse of femoral head. It could provide a wide clinical foreground.
Biocompatible Materials ; chemistry ; Bone Substitutes ; chemical synthesis ; chemistry ; Calcium Phosphates ; chemistry ; Computer-Aided Design ; Femur Head Necrosis ; therapy ; Humans ; Porosity ; Prostheses and Implants ; Tissue Engineering ; Tissue Scaffolds ; chemistry