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Osteoporotic fractures seriously endanger the elderly quality of life, especially postmenopausal women. Currently, calcium phosphate cement (CPC) is one of the materials used for the treatment of osteoporotic fractures. This study intends to investigate the biological effects of lithium (Li)-doped CPC. Li was dissolved into ultrapure water as curing solution to prepare CPC@Li composite material. Li did not affect the morphology of CPC. CPC@Li composite showed a sustained release of Li in 14 days. Compared with CPC, CPC@Li promoted the adhesion, proliferation, and osteogenic differentiation of rat bone marrow stem cells. The result of femur implantation in an osteoporosis mouse model showed that a larger amount of new bone was formed surrounding the CPC@Li implant and closely to the implant surface, indicating favorable osteogenesis and osteointegration capabilities. Li-doped CPC is promising to be used in clinic for its enhanced bone regeneration ability.

In this study, tricalcium silicate (C 3 S) calcium/polyphosphate/polyvinyl alcohol organic-inorganic self-setting composites were successfully designed. A variety of tests were conducted to characterize their self-setting properties, mechanical properties, degradation properties, and related biological properties. The composite bone cements showed a short setting time (5.5-37.5 min) with a 5:5-6:4 ratio of C 3 S/CPP to maintain a stable compressive strength (28 MPa). In addition, PVA effectively reduced the brittleness of the inorganic phase. Degradation experiments confirmed the sustainable surface degradation of bone cement. A maximum degradation rate of 49% was reached within 56 days, and the structure remained intact without collapse. Culturing MC3T3 cells with bone cement extracts revealed that the composite bone cements had excellent biological properties in vitro . The original extract showed a proliferation promotion effect on cells, whereas most of the other original extracts of degradable bone cements were toxic to the cells. Meanwhile, extracellular matrix mineralization and alkaline phosphatase expression showed remarkable effects on cell differentiation. In addition, a good level of adhesion of cells to the surfaces of materials was observed. Taken together, these results indicate that C 3 S/CPP/PVA composite bone cements have great potential in bone defect filling for fast curing.

In this work, a modified dicalcium phosphate dihydrate (DCPD) bone cement with unique biodegradable ability in a calcium phosphate cement system was prepared by the hydration reaction of monocalcium phosphate monohydrate and calcium oxide and integration with pullulan (Pul), a non-toxic, biocompatible, viscous, and water-soluble polysaccharide that has been successfully used to improve defects in DCPD bone cement, especially its rapid solidification, fragile mechanical properties, and easy collapse. The effect of different contents of Pul on the structure and properties of DCPD were also studied in detail. The modified cement was characterised by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, ultraviolet-visible absorption, X-ray photoelectron spectroscopy analysis, and rheological property measurements. The results indicated that Pul promoted the hydration formation of DCPD, and interface bonding occurred between Pul and DCPD. With increasing content of Pul, the setting time of the DCPD bone cement increased from 2.6 min to 42.3 min, the compressive strength increased from 0 MPa to 20.4 MPa, and the anti-collapse ability also improved owing to the strong interface bonding, implying that the DCPD bone cement improved by Pul has better potential for application in the field of non-loading bone regenerative medicine compared to unmodified DCPD bone cement.

In this work, novel magnesium calcium phosphate/sodium alginate composite cements were successfully fabricated with a proper setting time (5-24 min) and high compressive strength (91.1 MPa). The physicochemical and biological properties of the cement in vitro were fully characterized. The composite cements could gradually degrade in PBS as the soaking time increase, and the weight loss reached 20.74% by the end of 56th day. The cements could induce the deposition of Ca-P layer in SBF. Cell experiments proved that the extracts of the composite cements can effectively promote the proliferation and differentiation of the mouse bone marrow mesenchymal stem cells (MSCs). These preliminary results indicate that the magnesium calcium phosphate/sodium alginate composite cements could be promising as potential bone repair candidate materials.

Bone cement based on poly(methyl methacrylate) (PMMA) powder and methyl methacrylate (MMA) liquid is a very popular biomaterial used for the fixation of artificial joints. However, there is a risk of this cement loosening from bone because of a lack of bone-bonding bioactivity. Apatite formation in the body environment is a prerequisite for cement bioactivity. Additionally, suppression of infection during implantation is required for bone cements to be successfully introduced into the human body. In this study, we modified PMMA cement with γ-methacryloxypropyltrimetoxysilane and calcium acetate to introduce bioactive properties and 2-( tert -butylamino)ethyl methacrylate (TBAEMA) to provide antibacterial properties. The long-term antibacterial activity is attributed to the copolymerization of TBAEMA and MMA. As the TBAEMA content increased, the setting time increased and the compressive strength decreased. After soaking in simulated body fluid, an apatite layer was detected within 7 days, irrespective of the TBAEMA content. The cement showed better antibacterial activity against Gram-negative E. Coli than Gram-positive bacteria; however, of the Gram-positive bacteria investigated, B. subtilis was more susceptible than S. aureus .

Curcumin (Cur) is an active ingredient of Curcuma longa. Cur has many pharmacological effects, such as anti-inflammation, anti-oxidation, anticoagulation, hypolipidemic, anti-angiogenesis and anti-cancer. An injectable curcumin loaded chitosan/hydroxyapatite bone cement (Cur-CS/HA) was prepared as a bone scaffold and drug delivery. Tween 20, a nonionic surfactant, was incorporated into the cement to improve the solubility of curcumin. Four types of Cur-CS/HA (Group0, Group1, Group5 and Group10) were prepared with different Tween 20 ratios (0, 1, 5 and 10%, respectively). The samples were characterized by infrared spectroscopy (IR), X-ray diffraction (XRD) and scanning electron microscope (SEM). Compression tests were carried out to evaluate the strength of the scaffolds. In addition, the inhibition assay was carried out on MG63 cells with the extracts of drug loaded materials. The results showed that Cur had an effect on the setting time (p < 0.05). Cur reduced the compressive strength of the CS/HA cement (p < 0.05). The release studies showed that Tween 20 could effectively improve the solubility of curcumin. When the Tween 20 content in cement increased from 0 to 10%, the cumulative release (30 d) of Cur increased from 5.5 to 10.6%. Moreover, the cement had good injectability, good anti-collapsibility and good biocompatibility to meet the clinical requirements. The result of inhibition assay showed that Cur-CS/HA could inhibit the proliferation of MG63 cells. Tween 20 incorporated Cur-CS/HA had great potential to use as a drug-loaded artificial bone material.

Poly (methyl methacrylate) (PMMA) bone cement is widely used for anchoring joint arthroplasties. In cement brands approved for these procedures, micron-sized particles (usually barium sulphate, BaSO 4 ) act as the radiopacifier. It has been postulated that these particles act as sites for crack initiation and subsequently cement fatigue. This study investigated whether alternative radiopacifiers, anatase titanium dioxide (TiO 2 ) and yttria-stabilised zirconium dioxide (ZrO 2 ), could improve the in vitro mechanical, fatigue crack propagation and biological properties of polymethyl methacrylate (PMMA) bone cement and whether their coating with a silane could further enhance cement performance. Cement samples containing 0, 5, 10, 15, 20 and 25%w/w TiO 2 or ZrO 2 and 10%w/w silane-treated TiO 2 or ZrO 2 were prepared and characterised in vitro in terms of radiopacity, compressive and bending strength, bending modulus, fatigue crack propagation, hydroxyapatite forming ability and MC3T3-E1 cell attachment and viability. Cement samples with greater than 10%w/w TiO 2 and ZrO 2 had a similar radiopacity to the control 10%w/w BaSO 4 cement and commercial products. The addition of TiO 2 and ZrO 2 to bone cement reduced the bending strength and fracture toughness and increased fatigue crack propagation due to the formation of agglomerations and voids. Silane treating TiO 2 reversed this effect, enhancing the dispersion and adhesion of particles to the PMMA matrix and resulted in improved mechanical properties and fatigue crack propagation resistance. Silane-treated TiO 2 cements had increased nucleation of hydroxyapatite and MC3T3-E1 cell attachment in vitro , without significantly compromising cell viability. This research has demonstrated that 10%w/w silane-treated anatase TiO 2 is a promising alternative radiopacifier for PMMA bone cement offering additional benefits over conventional BaSO 4 radiopacifiers.

Recommendation: There is a paucity of data regarding total ankle arthroplasty (TAA) in patients with prior infection involving the ankle, whether it be septic arthritis, osteomyelitis, or infection of the surrounding soft tissues. We recommend that patients with prior infections in the affected ankle be worked up for infection, including a thorough history and physical examination, as well as ordering serologic tests and possible aspiration of the joint. During ankle arthroplasty in patients with prior infection, antibiotics should be added to the cement (if used), and the joint should be thoroughly cleansed. Intraoperative cultures of bone and soft tissue should also be obtained., Level of Evidence: Consensus., Delegate Vote: Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Recommendation: Unknown. There is insufficient evidence for the routine use of antibiotic-impregnated cement during primary total ankle arthroplasty (TAA)., Level of Evidence: Consensus., Delegate Vote: Agree: 100%, Disagree: 0%, Abstain: 0% (Unanimous, Strongest Consensus).

Background: As the major inorganic component of natural bone, nano-hydroxyapatite (n-HA) on its own is limited in its use in bone repair, due to its brittleness. Chitosan (CS) and sodium alginate (SAL) are used to reduce its brittleness and tendency to degradation. However, the compressive strength of the composite is still low, and its biological performance needs further study., Methods: Nano-hydroxyapatite/sodium alginate/chitosan (n-HA/SAL/CS) composite was prepared via an in situ synthesis method. Further, we prepared the n-HA/SAL/CS self-setting bone repair material by mixing n-HA/SAL/CS powder with a curing liquid (20 wt.% citric acid). In addition, the in vitro bioactivity and cell cytotoxicity were also explored., Results: Transmission electron microscopy photos revealed that the n-HA crystals were uniformly distributed throughout the polymer matrix. Infrared IR spectroscopy indicated that the HA interacted with the COO - of SAL and NH 2 - of CS. The compressive strength of the n-HA/SAL/CS bone cement was 34.3 MPa and matched the demands of weight-bearing bones. Soaking in vitro in simulated body fluid demonstrated that the composite material had reasonably good bioactivity, while cytotoxicity tests indicated that the n-HA/SAL/CS cement could promote cell proliferation and was biocompatible., Conclusions: Compressive strength of n-HA/SAL/CS can satisfy the needs of cancellous bone, and in vitro bioactivity and cytotoxicity tests results indicated that the n-HA/SAL/CS composite could act as an optimal bone repair material.

Introduction: Because of its good osteoconductivity, strontium (Sr) ranelate has been extensively used as a bone substitute for the treatment of bone disorders. To facilitate treatment, Sr is also incorporated into calcium phosphate cement (Sr-CPC); however, the Sr from Sr-CPC is not sufficient to induce a significant increase of bone mass in an ovariectomized rat model. To improve the efficiency of Sr-CPC, we developed a calcitonin gene-related peptide (CGRP)- and Sr-enriched CPC (CGRP-Sr-CPC)., Methods: We used X-ray diffraction and Fourier transform infrared spectroscopy to measure properties of CGRP-Sr-CPC. We also employed a cell proliferation assay, alkaline phosphatase (ALP) assay and real-time PCR to assess the effects of CPC implants on proliferation and differentiation of bone mesenchymal stem cells (BMSCs) from an ovariectomized rat model., Results: CGRP did not change the composition, pore sizes and compressive strength of the cement body as compared with Sr-CPC. Meanwhile, CGRP-Sr-CPC did not show cell cytotoxicity to BMSCs. Further, CGRP and Sr released from CGRP-Sr-CPC significantly enhanced the cell proliferation of BMSCs and increased the activity of ALP during differentiation of BMSCs, compared with CGRP- or Sr-CPC. Moreover, CGRP-Sr-CPC significantly up-regulated the expression levels of osteogenic differentiation-related genes including Alp, Bmp2, Osteonectin and Runx2 during differentiation., Conclusions: These findings demonstrate the optimized effects of CGRP- and Sr-enriched CPC in promoting proliferation and osteogenic differentiation of BMSCs, suggesting the potential ability of this novel cement to assist the formation of new bone during osteoporosis-induced bone disorders.

Acrylic bone cements have an elastic modulus several times higher than the surrounding trabecular bone. This has been hypothesized to contribute to certain clinical complications. There are indications that the addition of specific fatty acids and triglyceride oils may reduce the elastic modulus of these types of cements. Some of these additives also appear to have inherent antibiotic properties, although this has never been evaluated in bone cements. In this study, several types of fatty acids and triglyceride oils were evaluated for use in acrylic bone cements. Their mechanical properties were evaluated under uniaxial compression testing and selected cements were then further characterized in terms of microstructure, handling and antibacterial properties using scanning electron microscopy, polymerization temperature measurements, agar diffusion tests and bactericidal activity assays of cement extracts. It was found that any of the evaluated fatty acids or triglyceride oils could be used to tailor the stiffness of acrylic bone cements, although at varying concentrations, which also depended on the type of commercial base cement used. In particular, the addition of very small amounts of linoleic acid (<2.0 wt%) resulted in Young's moduli and compressive strengths in the range of human trabecular bone, while maintaining a similar setting time. Further, the addition of 12.6 wt% ricinoleic acid to Osteopal V cement was found to have a significant antibacterial effect, inhibiting growth of Staphylococcus aureus in an agar diffusion test as well as demonstrating 100% bactericidal activity against the same strain., (© The Author(s) 2015.)

Purpose: Proximal femoral bone loss is a common challenge in revision hip arthroplasty. In this study, in-vitro fixation of a non-cemented, rectangular, dual-tapered, press-fit femoral component designed to achieve metadiaphyseal fixation was analyzed using an accelerated proximal femoral bone loss model to assess the potential use in revision cases., Methods: The press-fit AlloclassicTM femoral stem was implanted in ten cadaveric femurs and tested under cyclic biomechanical loading in an intact state, and then again after sequential proximal femoral bone resections, simulating increasing amounts of bone deficiency. Anterior-posterior and medial-lateral interface motions were measured at the distal stem tip throughout loading. 
, Results: Three specimens remained stable throughout testing, with initial and peak per-cycle motions of less than 50 μm. Six specimens were destabilized under loading with higher per-cycle motions, specifically at the distal stem tip during peak loading in the anterior-posterior direction, with motions of 78±69 μm, compared to 12±9 μm in the stable specimens (P<.05). Total migration of the destabilized specimens was also significantly higher, specifically at the proximal stem tip in the medial-lateral direction, with migrations of 101±34 μm (P<.05) and at the distal stem tip in the anterior-posterior direction, with migrations of 155±179 μm (P<.05), compared to 33±12 μm and 13±11 μm for the stable specimens., Conclusion: The results indicate that when strong initial fixation is achieved, long-term success is possible given substantial proximal femoral bone loss.

Bio-convertible artificial bone with slow release of anti-osteoporosis drug is useful to treat osteoporosis. Apatite cement containing 6% simvastatin (APD) had lower crystallinity than natural bone. In-vitro drug release tests in simulated body fluid (pH 7.8) and acetate buffer (pH 4.5) were performed at 37.0 C as physical models of osteoblast and osteoclast conditions (SOB and SOC). The device had lower drug release rate under SOB, but significantly higher rates under SOC. The simvastatin release rate changed depending on dissolution media, it repeated twice, and the rate under SOC was 15 times higher than under SOB. The device showed dissolution medium responsive drug release. After implantation of the APD in osteoporosis rats, the bone mineral density was evaluated by the x-ray computed tomography. The result indicated that the bone mineral density of APD implanted rat was significantly higher than that of control diseased. The result indicated that the device was therapeutically useful to bone regeneration.

We developed a novel calcium phosphate cement (CPC) by combining the silk fibroin and osteogenic supplements (β-glycerophosphate, ascorbic acid, and dexamethasone) with α-tricalcium phosphate cement. Mesenchymal stem cells (MSCs) were cultured on the novel CPC scaffold. Results showed that the novel CPC scaffold was biocompatible and favorable for the adhesion, spreading, and proliferation of MSCs. Osteogenic differentiation of MSCs was confirmed by high osteocalcin content and elevated gene expressions of bone markers, such as alkaline phosphatase, collagen type I, and osteocalcin. Therefore, the novel CPC scaffold may be potentially useful for implant fixation and more rapid new bone formation in moderate load-bearing applications.

Infection following surgery can result in significant pain and morbidity for patients undergoing vertebroplasty/kyphoplasty, and often results in revision surgery. This study focuses on the development of Al-free glass polyalkenoate cements (GPCs) based on 0.04SrO-0.12CaO-0.36ZnO-0.48SiO( 2) glass, with the intent of optimizing their antibacterial efficacy by incorporating low-molecular-weight polyacrylic acids (PAA) and trisodium citrate (TSC), and evaluating the resultant GPCs against bacteria relevant to spinal infections, P. aeruginosa and E. coli. Ion-release profiles were determined for the GPC formulation containing E6 PAA (Cement A) and E7 PAA (Cement B), and Zn, Na, and Sr release was recorded over 1, 7, and 30 days. Inhibition was found in E. coli at each time period (0-30 days) and this generally decreased with exposure time in water. The largest GPC inhibition zones were produced by Cement A (6 mm); however the control material Simplex P + tobramycin produced much higher inhibition zones (11 mm). When testing the GPC against P. aeruginosa, inhibition was only present at the 0-day time period. Simplex P + tobramycin was found to produce inhibition at each time frame. Analysis of the agar from the inhibition zone of the E. coli test revealed that there is a significant change in Zn concentration as compared to a control agar specimen, which suggests that Zn release is responsible for the antibacterial effect of the GPCs.

Purpose: To compare the effectiveness of pulse-lavage brushing followed by hydrogen peroxide-gauze packing with either technique alone or normal-saline irrigation in bone-bed preparation for cemented total hip arthroplasty., Methods: 44 fresh-frozen ox femoral canals were prepared for cemented total hip arthroplasty using 4 techniques: normal-saline irrigation, pulse-lavage brushing, hydrogen peroxide-soaked gauze packing, and a combination of the latter 2 techniques. The maximum tensile pull-out force required to separate the prosthesis from the femoral canal was measured as an indicator of the strength of the cement-bone interface., Results: The mean pull-out force to separate the prosthesis from the femoral canal was significantly higher in specimens prepared with pulse-lavage brushing followed by hydrogen peroxide-soaked gauze packing or pulse-lavage brushing alone than those prepared with normal-saline irrigation or hydrogen peroxide-soaked gauze packing alone (p<0.001)., Conclusions: Pulse-lavage brushing is more effective at cleansing the femoral canal and increasing mechanical strength at the cement-bone interface than preparation with normal-saline irrigation or hydrogen peroxide-soaked gauze packing.

The arterial blood gas chemistry was measured continuously in ten patients during primary cemented total hip replacement in order to define more precisely the patterns of changes in blood gases during various stages of the operation. All ten patients demonstrated significant drops in PaO2 after femoral cement implantation and nine of the ten after acetabular cement implantation. The mean drop in PaO2 following acetabular cement expressed as mean +/- SD was 18 +/- 8 mmHg (16 +/- 6%) (P < 0.05) and femoral cement application was 25 +/- 11 mmHg (23 +/- 9%) (P < 0.05). For changes in PaO2 there were corresponding drops in SpO2 in all patients with the femoral cement and in eight patients with the acetabular cement. The mean drop in SpO2 following the application of acetabular and femoral cements respectively were 1.7 +/- 1.5% and 3 +/- 2.45%. No changes in blood PaO2 were observed during dislocation of the hip joint or reaming of acetabulum and femur. In vitro studies revealed no effect of the liquid monomer or the cured cement on the performance of the Clark electrode of the sensor. We suggest that significant drops in PaO2 occur with both acetabular and femoral cement implantation and that the derangements in blood PaO2 last longer than detected by pulse oximetry following cement implantation.