Application Of Bone Cement Research Articles

Incorporation of Methotrexate in Calcium Phosphate Cement: Behavior and Release in Vitro and in Vivo

The application of antibiotic-loaded calcium phosphate bone cement in the treatment and prevention of osteomyelitis suggests that calcium phosphate cement could also be used as an anticancer drug carrier to reduce the local recurrence of bone tumors and systemic toxicities of chemotherapy. We added 0 to 400 mg of methotrexate to 40 g cement, with final methotrexate concentrations of 0% to 1% (weight/weight). The setting times, mechanical properties, microstructures, and in vitro methotrexate release kinetics of these methotrexate-calcium phosphate bone cement specimens were evaluated, along with in vivo methotrexate release kinetics in 24 rabbits. Methotrexate did not significantly alter the cement setting time. The compressive and tensile strengths of the methotrexate-calcium phosphate bone cement specimens were significantly less when 400 mg methotrexate was used, compared to control samples without methotrexate addition. Nevertheless, the cement remained compliant with the minimum requirements for clinical application. The scanning electron microscopy micrographs showed that the basic crystal structure did not alter. The methotrexate release kinetics in vitro and in vivo confirmed that methotrexate-calcium phosphate bone cement was a monolithic matrix system, with a burst effect in the initial stage and a sudden drop thereafter. Drug delivery in vivo was faster than in vitro. We estimated that the incorporated methotrexate could be continuously released over 2 to 4 months at a higher than minimum concentration. The methotrexate had no apparent toxicity on the host rabbits, even at the highest dose of methotrexate tested. The methotrexate-calcium phosphate bone cement system may be a potentially effective therapy for bone tumors in humans.

Pretibial Full Thickness Skin Burn following Indirect Contact from Bone-Cement Use in a Giant Cell Tumour

Bone cement reaches significant temperatures and is known to cause thermal and chemical damage to various tissues. All the reports of such damage occurred following a direct contact of the tissue or structure with cement. We report the case of a patient with a giant cell tumour of the proximal tibia who underwent curettage and bone cement application through a posterior approach and subsequently developed full thickness pretibial skin damage despite showing no evidence of any direct contact of the involved skin with bone cement. This is the first report of its kind and though anecdotal is a serious complication that surgeons should be aware of.

Intra-abdominal Application of Bone Cement for Uncontrollable Perivertebral Hemorrhage

Extensive bleeding from the perivertebral space is a rare encountered problem in abdominal trauma surgery. In this report, we present a technique for the hemostasis of perivertebral hemorrhage apart from the conventional hemostatic measures in a patient with penetrating injury to the lumbar artery and tributaries. In order to construct a controlled compartment in the retroperitoneal perivertebral cavity, bone cement was plastered alongside the dissection plane near the vertebral wall and hemostasis was achieved. Bone cement application, therefore, may pose as an alternative hemostatic method for patients with uncontrollable bleeding in the perivertebral compartment.

The effect of cementing technique on structural fixation of pegged glenoid components in total shoulder arthroplasty

Although loosening of cemented glenoid components is one of the major complications of total shoulder arthroplasty, there is little information about factors affecting initial fixation of these components in the scapular neck. This study was performed to assess the characteristics of structural fixation of pegged glenoid components, if inserted with two different recommended cementing techniques. Six fresh-frozen shoulder specimens and two types of glenoid components were used. The glenoids were prepared according to the instructions and with the instrumentation of the manufacturer. In 3 specimens, the bone cement was inserted into the peg receiving holes (n = 12) and applied to the back surface of the glenoid component with a syringe. In the other 3 specimens, the cement was inserted into the holes (n = 15) by use of pure finger pressure: no cement was applied on the backside of the component. Micro-computed tomography scans with a resolution of 36 microm showed an intact cement mantle around all 12 pegs (100%) when a syringe was used. An incomplete cement plug was found in 7 of 15 pegs (47%) when the finger-pressure technique was used. Cement penetration into the cancellous bone was deeper in osteopenic bone. Application of bone cement on the backside of the glenoid prosthesis improved seating by filling out small spaces between bone and polyethylene resulting from irregularities after reaming or local cement extrusion from a drill hole. The fixation of a pegged glenoid component is better if the holes are filled with cement under pressure by use of a syringe and if cement is applied to the back of the glenoid component than if cement is inserted with pure finger pressure and no cement is applied to the back surface of the component.

Osteoporotic Vertebral Fractures

Due to a demographic increase in patients with osteoporosis the epidemiology of vertebral fractures changes. Osteoporosis is characterized by low bone density, microarchitectural deterioration of bone tissue and impaired bone strength, which leads to an increased bone fragility and susceptibility to fracture. Asymptomatic vertebral deformity was found to be associated with subsequent risk of symptomatic fractures, particularly vertebral fracture, and increased risk of mortality after a fracture. After the first osteoporotic fracture at any site the risk for further fractures increases dramatically. Osteoporosis represents, besides the origin of such vertebral fractures and impaired bone healing, a problem in osteofixation and implant stability in fracture treatment in orthopedic surgery. Two new treatment strategies of percutaneous vertebro- and kyphoplasty have gained worldwide attention in the treatment of osteoporotic vertebral fracture and short-term observational studies and case-control studies indicate that the results are favorable, regarding both pain relief and functional status. Actually, it cannot be decided whether the internal application of bone cement to the vertebral body is effective in the long run. Special attention has to be given to the underlying osteoporosis in order to reduce the incidence of further fractures in the patients at risk. Diagnosis and treatment of osteoporosis have to be part of the treatment concept of osteoporotic vertebral fractures. Thus, it is important that orthopedic surgeons identify, assess and treat patients with fragility fractures for osteoporosis according to the currently available treatment protocols.

Anterior spinal column augmentation with injectable bone cements

A vertebral fracture, whether originating from osteoporosis or trauma, can be the cause of pain, disability, deformation and neurological deficit. The treatment of vertebral compression fractures has, for many years until the advent of vertebroplasty, consisted of bedrest and analgesics. Vertebroplasty is a percutaneous technique during which bone cement is injected in a vertebral body to provide immediate pain relief by stabilization. Inflatable bone tamps can, prior to the injection of cement, be used to create a void in the vertebral body, in which case the technique is known as balloon vertebroplasty (or kyphoplasty). The chance of extracorporal cement leakage is smaller for balloon vertebroplasty than for vertebroplasty. Some authors also claim to have gained some correction in vertebral body height or angulation. Both interventions can be used for several indications, including osteoporotic compression fractures and osteolytic lesions of the vertebral body such as myeloma, hemangioma or metastasis, and also for traumatic burst fractures in combination with pedicle screw instrumentation. Polymethyl methacrylate cement is the bone void filler that is used most frequently, although the application of calcium phosphate cements has been studied widely in vitro, in vivo and also in small-scale clinical series. The clinical results of (balloon-) vertebroplasty are favorable with 85–95% of all patients experiencing immediate and long-lasting relief of pain. Serious complications are relatively rare but include neurological deficit and pulmonary embolism. In this paper, both vertebroplasty and balloon vertebroplasty and their respective indications, techniques and results are described in relation with the application and limitations of permanent and resorbable injectable bone cements.

Current attitudes towards cementing in TKR: a national survey amongst members of the BASK

Respondents 198 (66%) Regularly perform TKR 184 Use cemented components 155 (84%) Use uncemented components 18 (10%) Hybrid 11 (6%) Patella resurfacing Routinely 71 (39%) Never 28 (15%) Only if necessary 85 (46%) Routine use of tourniquet 165 (90%) Pulse Lavage Regularly use 137 (75%) Never 25 (14%) Occasional 22 (11%) Brush (Out of 166 who use cement) Routinely 13 (8%) In 1999 the BOA and BASK published a joint document dKnee replacement: a guide to good practiceT as a consensus statement of best practice in total knee replacement. It is recommended that dIn cemented knee replacement the bone surfaces should be cleaned, irrigated and dried before application of bone cement, and cement should be compressed where possibleT. We intended to assess the current practice of total knee replacements amongst the members of the BASK with particular emphasis on the cementing techniques, and to evaluate the present practice in accordance to the guideline issued by the BOA and BASK. A short postal questionnaire was designed and sent to all 300 members of the British Association for Surgeons of the Knee (BASK) as of 2002.

Surface studies on acrylic bone cement

Poly(methyl methacrylate) (PMMA) is used to fill the gap between the prosthesis and the surrounding bone in cemented arthroplasties. Biocompatibility problems related to bone cement application limit the clinical success of these cemented arthroplasties. Being the cement surface in close connection with the living bone, it is reasonable to assume that surface properties such as, surface composition and surface energy, will play a role in the biomaterial performance. X-ray photoelectron spectroscopy (XPS) analysis and surface energy studies were carried out during 4 months, in order to assess a possible correlation between aging time and surface changes. The aging of PMMA, in a biological model fluid, strongly influences the composition and wettability of the cement surface. These changes may be explained through the hydrolysis of PMMA ester groups and the subsequent hydrogen bonding. Although our study does not exactly reproduce the in vivo environment surrounding a prosthesis, it suggests that the changes in the composition and wettability of the surface may modulate the host response towards the implant, thus contributing to its loosening.

Surface studies on acrylic bone cement

Poly(methyl methacrylate) (PMMA) is used to fill the gap between the prosthesis and the surrounding bone in cemented arthroplasties. Biocompatibility problems related to bone cement application limit the clinical success of these cemented arthroplasties. Being the cement surface in close connection with the living bone, it is reasonable to assume that surface properties such as, surface composition and surface energy, will play a role in the biomaterial performance. X-ray photoelectron spectroscopy (XPS) analysis and surface energy studies were carried out during 4 months, in order to assess a possible correlation between aging time and surface changes. The aging of PMMA, in a biological model fluid, strongly influences the composition and wettability of the cement surface. These changes may be explained through the hydrolysis of PMMA ester groups and the subsequent hydrogen bonding. Although our study does not exactly reproduce the in vivo environment surrounding a prosthesis, it suggests that the changes in the composition and wettability of the surface may modulate the host response towards the implant, thus contributing to its loosening.

Mechanical behaviour of a new acrylic radiopaque iodine-containing bone cement

In total hip replacement, fixation of a prosthesis is in most cases obtained by the application of methacrylic bone cements. Most of the commercially available bone cements contain barium sulphate or zirconium dioxide as radiopacifier. As is shown in the literature, the presence of these inorganic particles can be unfavourable in terms of mechanical and biological properties. Here, we describe a new type of bone cement, where X-ray contrast is obtained via the introduction of an iodine-containing methacrylate copolymer; a copolymer of methylmethacrylate and 2-[4-iodobenzoyl]-oxo-ethylmethacrylate (4-IEMA) is added to the powder component of the cement. The properties of the new I-containing bone cement (I-cement) are compared to those of a commercially available bone cement, with barium sulphate as radiopacifier (B-cement). The composition of the I-cement is adjusted such that similar handling properties and radiopacity as for the commercial cement are obtained. In view of the mechanical properties, it can be stated that the intrinsic mechanical behaviour of the I-cement, as revealed from compression tests, is superior to that of B-cement. Concerning the fatigue behaviour it can be concluded that, though B-cement has a slightly higher fatigue crack propagation resistance than I-cement, the fatigue life of vacuum-mixed I-cement is significantly better than that of B-cement. This is explained by the presence of BaSO 4 clumps in the commercial cement; these act as crack initiation sites. The mechanical properties (especially fatigue resistance) of the new I-cement warrant its further development toward clinical application.

Application of Bioactive Bone Cement as Substitution Material on the Treatment of Implant Surgery

Application of Bioactive Bone Cement as Substitution Material on the Treatment of Implant Surgery

Percutaneous Balloon Kyphoplasty in Vertebral Body Compression Fracture: A case report

Vertebral body compression fractures can cause chronic back pain and may result in progressive kyphosis. Traditional treatment for patients with vertebral body compression fractures includes bed rest, analgesics, and bracing. Vertebroplasty has been used to alleviate pain and enhance stability of spine. This technique, however, can not restore the height of the collapsed vertebral body and carries the potential risk of serious complications, such as paralysis due to cement leakage into the epidural space. Percutaneous balloon kyphoplasty is a novel technique, which involves the introduction of inflatable bone tamps into the fractured vertebral body to elevate the endplates, prior to fracture fixation with bone cement. Kyphoplasty, therefore, can offer the advantages of realigning the spinal column and regaining the height of the fractured vertebra, which may be helpful to decrease the pulmonary, GI, and the early morbidity consequences related to these fractures. In addition, it reduces the risk of serious complications following kyphoplasty. We performed percutaneous balloon kyphoplasty on a 69-year-old female with L5 vertebral compression fracture 5 days after fracture. The bone tamp was inflated by raising the pressure to 200 psi. Polymethylmethacrylate bone cement application was complete at 4 ml to the left side and 3 ml to the right side of vertebral body. The focal kyphosis was corrected from 2.5o back to neutral alignment. The height restoration was 4.2 mm at midvertebral body. The patient experienced significant pain relief after the procedure and expressed satisfaction with the treatment.

Increasing bone screw anchoring in the femur head by cement administration via the implant--a biomechanical study

Osteoporosis reveals a higher risk of fractures. Due to the lack of possibilities to anchor fixation elements, fracture treatment often turns out to be complicated. An experimental study served to investigate the extent to which the application of bone cement through a modified gliding screw (Dynamic Hip Screw DHS) would improve the screw anchoring in osteoporotic femoral heads. Quasi-static compressive and torsional load tests were used to assess the desired improvement of the screw anchoring. Cadaver femur pairs served to compare the cement augmentation to the uncemented contralateral control. The improvement of the holding strength of the screw under static compressive and torsional load depended on the cement flow into the adjacent bone tissue. The filling with additional cement was only successful after having created a small hollow space at the screw tip with a special instrument. Consequently, under compression as well as torsion, the cement application yielded improvements from 17% up to several times as much. In the application of gliding screws in osteoporotic femoral heads, the locally limited cement application through the implant has been shown to be a biomechanical possibility to improve screw fixation.

Biodegradable bone cement compositions based on acrylate and epoxide terminated poly(propylene fumarate) oligomers and calcium salt compositions

The synthesis of biodegradable bone cement compositions is presented. These bone cement compositions can be applied as a putty-like mixture and harden to a strong material in a bone fracture. They degrade from the site of application to allow the ingrowth of new bone for complete healing of the bone fracture. The bone cement is composed of a solid particulate phase dispersed in an initially liquid polymeric phase, which can be hardened by cross-linking. The polymeric phase is a low-molecular-weight liquid poly(propylene fumarate) (PPF) containing double bonds available for cross-linking. The solid particulate phase consists of calcium carbonate and tricalcium phosphate. PPF oligomers of M w = 1800 and M n = 750 were prepared from the condensation of non-volatile bis(2-hydroxypropyl fumarate) and propylene-bis(hydrogen maleate) trimers. PPF terminated divinyl and diepoxide derivatives were obtained from the reactions between PPF diol and acryloyl chloride or epichlorhydrin, respectively. Putty-like cement compositions were prepared from a mixture of 30 wt% polymer phase containing benzoyl peroxide-dimethyl toluidine as polymerization catalyst and 70 wt% calcium salts. The divinyl and diepoxide terminated PPF oligomers provided a high strength composition of between 30 and 129 MPa which is suitable for bone cement applications. In vitro hydrolysis of the composites showed little weight loss with the compressive strength remaining above 20 MPa after 4 weeks in buffer solution. Compositions of the PPF oligomers cross-linked without calcium salts showed a gradual weight loss (10–65 wt% after 4 weeks) when placed in buffer solution followed by high water absorption (18–200 wt% after 4 weeks), with the epoxide terminated PPF being the least to degrade or absorb water.

Development of chronic mandibular osteomyelitis in a miniswine model

Previous attempts to develop a reproducible model of chronic mandibular osteomyelitis have met with limited success. In this study, osteomyelitis was produced in the mandibles of eight adult Yucatan miniswine by the intramedullary application of sodium morrhuate, Staphylococcus aureus, and either polymethylmethacrylate bone cement or bone wax. At 8 weeks' postinfection, the mandibles were surgically debrided and specimens were obtained for culture. Although all of the animals developed clinical evidence of osteomyelitis that was supported by positive cultures, the original organism (S aureus) was recovered only from those animals where bone wax had been used to seal the cortical defects. This animal model may be useful for evaluating newer treatment modalities for chronic osteomyelitis.

The technique of cemented total hip arthroplasty

The success of cemented total hip arthroplasty is dependent on the quality of cement techniques. The techniques can be divided into three groups: bone preparation, cement application, and prosthesis insertion. Modern cement techniques have improved the results of total hip arthroplasty. Careful adherence to each of the steps throughout the procedure remains of critial importance and will maximize the opportunity for successful long-term results.

Mechanical effects of reaming and implantation of acrylic cement into the medullary cavity of bones.

Changes in the mechanical properties of the rat femur caused by intramedullary application of bone cement were studied. In one group of animals reaming of the medullary cavity was performed, and bone cement was injected. In a control group only reaming was performed. At various intervals from day 0 to day 180 following operation the mechanical characteristics of the bone were evaluated. Reaming of the medullary cavity provoked a temporarily reduced bending moment of the femur at 40 days after operation. Intramedullary bone cement caused no significant changes in the bending moment of the femora until day 180 after operation. At this time, the bending moment of the cemented femora was significantly greater than that of the contralateral bones. This may be attributed to more periosteal bone being deposited, as implantation of bone cement induced a significant increase in periosteal reaction. The elastic stiffness of the bone was not altered either by reaming or the implantation of bone cement. It is concluded that reaming and implantation of bone cement into the medullary cavity do not impair the mechanical properties of the femur in the young rat.

Direct effects of acryl bone cement monomer on isolated heart muscle.

Experiments were carried out in isolated dog heart muscle to determine the direct effect of acryl bone cement monomer on the myocardial contractility. The monomer caused a dose-dependent decrease in the maximum velocity of shortening (Vmax) and the maximum force development (Fm), consequently resulting in a leftward shift of the force-velocity relation curves. There was also a concomitant decrease in work, power, the maximum rate of force development (max dF/dt) and time to peak force (TPF) from the onset of force development. These results indicate that acryl bone cement monomer exerts a direct negative inotropic effect on the myocardium and that the myocardial depression due to free monomer absorbed from the mixed bone cement into the systemic circulation during operation seems to be one of the major causes of the cardiovascular complications associated with the clinical application of bone cement.