Polymethylmetacrylate Bone Cement Research Articles

Minimal Invasive Percutaneous Kyphoplasty of C1 Lytic Lesion Using an Intraoperative 3D Imaging-Based Navigation System and Fluoroscopy

Background: Percutaneous kyphoplasty is a minimally-invasive techniques that aim to provide pain relief and bone stabilization by the injection of cement. Metastatic lesions of the atlas treated by this technique has been described in only few articles. Objective: We describe the use of kyphoplasty in a painful osteolytic lesion located in the left mass lateral of C1 with a postero lateral approach using 3D CT-scann intraoperative navigation system and fluoroscopy. Methods: A 58 year-old woman with metastastic breast neoplastic which admitted for treatment severe left-sided suboccipital exacerbated by head rotation and neck pain refractory to conventional medical treatment painkillers. CT scan and magnetic resonance imaging of the cervical spine revealed osteolytic destruction the left lateral mass of C1 . The patient underwent a percutaneous kyphoplasty managed using polymethylmetacrylate bone cement. Results: The patient reported post operative substantial pain relief . CT scan showed adequate filling of the osteolytic lesion without the obvious leakage of bone cement. the patient showed no clinical complications, while Clinical follow-up at 3 months revealed that this pain condition was improved and maintained. Conclusion: Minimally invasive percutaneous kyphoplasty using an intraoperative 3D navigation system and fluroscopy with postero lateral approach is a safe and effective alternative reducing post-operative morbidity and effective possibility in selected patients with C1 metastasis

Percutaneous Vertebroplasty and its Short Term Clinical Outcome

Background: Percutaneous vertebroplasty was found to be effective in treating osteoporosis-related compression fractures; it is also useful in treatment of hemangioma, multiple myeloma and metastasis. Objectives: This study was aimed to evaluate the short term clinical outcome of percutaneous vertebroplasty. Patients and Methods: Twenty-seven patients were enrolled into this descriptive analytical study after being informed on technical details of procedure and its pre- and post-operative cares. Polymethylmetacrylate bone cement was injected under continuous CT imaging guidance. The amount of injected cement in each treated vertebral body and any cement leakage was monitored. Results: The mean volume of injected cement was 6.22 2.24 (210) mL. The baseline, immediately after procedure and one week and one month post procedure pain scores were 8.11 1.69 7.85 1.59, 6.30 1.66 and 3.63 1.50, respectively. The pain was significantly reduced gradually after the procedure (P < 0.001). The baseline and immediately after procedure and one week and one month post procedure disability scores were 78.70 9.05, 58.52 13.99, 47.96 14.95, and 37.59 18.87, respectively. The disability significantly faded after the procedure (P < 0.001). Conclusions: Percutaneous vertebroplasty is an efficient technique with low complication rates and a significant reduction in pain.

A Clinical Comparative Study on Low Versus Medium Viscosity PolyMethylMetAcrylate Bone Cement in Percutaneous Vertebroplasty: Viscosity Associated With Cement Leakage

A Clinical Comparative Study on Low Versus Medium Viscosity PolyMethylMetAcrylate Bone Cement in Percutaneous Vertebroplasty: Viscosity Associated With Cement Leakage

A Clinical Comparative Study on Low Versus Medium Viscosity PolyMethylMetAcrylate Bone Cement in Percutaneous Vertebroplasty

Comparative, prospective follow-up study. Comparison of outcome between patients treated with Percutaneous VertebroPlasty (PVP) using low and medium viscosity PolyMethylMetAcrylate (PMMA) bone cement. Viscosity is the characterizing parameter of PMMA bone cement, currently the standard augmentation material in PVP, and influences interdigitation, cement distribution inside the vertebral body, injected volume and extravasation, thereby affecting the clinical outcome of PVP. Currently, low, medium, and high viscosity PMMA bone cements are used interchangeably. However, effect of viscosity on clinical outcome in patients with Osteoporotic Vertebral Compression Fractures (OVCFs) has not yet been explicit subject of investigation. Follow-up was conducted using a 0 to 10 Pain Intensity Numerical Rating Scale (PI-NRS) and the Short Form 36 (SF-36) Quality of Life questionnaire before PVP and at 7 days (PI-NRS only), 1, 3, and 12 months after PVP. Injected cement volume, degree of interdigitation, and cement leakage were analyzed on direct postoperative computed tomography scanning. At 6 and 52 weeks and at suspicion, patients were analyzed for new fractures. A total of 30 consecutive patients received PVP using low viscosity PMMA bone cement (OsteoPal-V) for 62 OVCFs, followed by 34 patients who received PVP using medium viscosity PMMA bone cement (Disc-O-Tech) for 67 OVCFs. Results regarding PI-NRS and SF-36 were comparable between both groups. Postoperative comparison of injected cement volume, degree of interdigitation, proportion of bipedicular procedures, incidence of new vertebral fractures and complications revealed no differences between both groups. Viscosity was identified as a risk factor for the occurrence of cement leakage (yes/no, OR: 2.925, 95% confidence interval: [1.072-7.984], P = 0.036). No major differences in clinical outcome after PVP in OVCFs using low and medium viscosity PMMA bone cement were found. Viscosity of PMMA bone cement was identified as an independent predictor of cement leakage.

An experimental comparison of different devices for pulsatile high-pressure lavage and their relevance to cement intrusion into cancellous bone

Some of the systems marketed for pulsatile high-pressure lavage are clearly different in their mechanical pulse characteristics. To take the matter further we set up an experimental in vitro model to determine whether these different lavage systems might produce different cementation results because of their differing pulse characteristics, and whether the systems differed significantly in terms of cement depth penetration. A total of 48 femoral heads were obtained at operation from patients who had undergone endoprosthetic hip replacement. The specimens were subjected to manual rinsing or semiautomatic cleansing procedures with five different pulsatile lavage devices. After the cleansing procedures, polymethylmetacrylate bone cement was intruded into the cancellous bone under standardised conditions. Determination of cement penetration was done by computed tomography using an image processing software. Irrespective of the nature of the lavage system tested, superficial cement penetration, both up to 2 mm and up to 3 mm, was significantly better after pulsatile high-pressure lavage than it was after manual rinsing of the specimens with a bladder syringe (P < 0.001 in each case). Whereas our experimental model did not show any significant differences between the lavage systems as regards the cementation results to a depth of up to 2 mm (P = 0.996), there were significant differences at a target depth of 3 mm (P < 0.05). As compared with manual rinsing, pulsatile high-pressure lavage in vitro makes highly significant improvements in cement penetration into cancellous bone and should be regarded as an indispensable component of modern cementation techniques for endoprosthetic surgery. Up to the present we have not been able to ascertain what influence the different pulse characteristics of a pulsatile lavage system may have on the intended cementation result, whether it is impact force, pulse shape, pulse duration, flow rate or frequency. Appropriate investigations will be necessary.

An in vitro assessment of the antibacterial properties and cytotoxicity of nanoparticulate silver bone cement

Infections with multiresistant bacteria have become a serious problem in joint arthroplasty. This study reports about in vitro antibacterial activity against multiresistant bacteria and in vitro cytotoxicity of polymethylmetacrylate bone cement loaded with metallic silver particles with a size of 5–50 nm called NanoSilver. In vitro antibacterial activity against S. epidermidis, methicillin-resistant S. epidermidis (MRSE), and methicillin-resistant S. aureus (MRSA) was studied by microplate proliferation tests. Quantitative elution testing and qualitative ongrowth of human osteoblasts was done to study in vitro cytotoxicity. Only NanoSilver cement showed high-antibacterial activity against all strains, including MRSE and MRSA. Gentamicin cement was not effective against MRSA and MRSE due to the high-level gentamicin resistance of the tested strains. Plain cement did not inhibit proliferation of any strains. There was no significant difference regarding in vitro cytotoxicty between NanoSilver and the non-toxic control. Cytotoxicity of cement loaded with silver salts made this kind of silver unsuitable for all day clinical use in the past. This new form of silver called NanoSilver was free of in vitro cytotoxicity and showed high effectiveness against multiresistant bacteria. If the results can be confirmed in vivo NanoSilver may have a high interest in joint arthroplasty.

Improved bonding strength of polyethylene/polymethylmetacrylate bone cement – a preliminary study

The adhesion of polymethylmetacrylate (PMMA) bone cement and low density polyethylene (LDPE) substrate by means of corona discharge treatment are presented. The surfaces were characterized by water contact angle goniometer, Fourier-transform infrared spectroscopy in the attenuated total reflectance mode (FTIR-ATR), electron spectroscopy for chemical analysis (ESCA), and scanning electron microscopy (SEM) for surface morphology. The bonding strength between bone cement and LDPE with varying intensity of corona treatment was evaluated by a 180 degrees peel test. The water contact angles decreased with increasing treatment intensity from 95.0 +/- 1.8 to around 43.5 degrees. It was observed that the oxygen containing groups as hydroxyl, ether, carboxylic acid, ester, ketone or aldehyde groups were introduced on the LDPE surfaces by corona treatment. The peel strength steeply increased from 0 to 1.75 kgf/cm with increasing the intensity of corona treatment. The improved adhesion of bone cement onto LDPE substrate may be due to only secondary force such as hydrogen bonding between PMMA bone cement and hydrophilized LDPE substrate.

887 Prosthesis for the treatment of metastatic bone disease of the hip: Effects of radiotherapy

Twenty-eight patients with metastatic involvement of the proximal femur were treated by resection and prosthetic replacement. A large femoral prosthetic component was routinely fixed with polymethylmetacrylate bone cement. Radiotherapy was delivered preoperatively in 2 and post-operatively in 7 patients. Postoperative pain (Habermann) was excellent in 81% and good in 15% of the patients. Hip functions (hip rating scale of Merle d’Aubigne) were rated as excellent in 19%, very good in 22% and good in 22% of the hips. Survival correlated with preoperative Karnofsky performance status (P < 0.01) and with the absence of postoperative pulmonary complications (P < 0.01). The radiographs of the 18 patients surviving 3 months or longer showed formation of a new bony envelope around the femoral prosthetic component in 11 cases (61%) and bone remodelling of the distal femur in 12 cases (67%). These changes occurred only if no radiotherapy had been delivered to the femur (P < 0.01). Twenty-eight patients with metastatic involvement of the proximal femur were treated by resection and prosthetic replacement. A large femoral prosthetic component was routinely fixed with polymethylmetacrylate bone cement. Radiotherapy was delivered preoperatively in 2 and post-operatively in 7 patients. Postoperative pain (Habermann) was excellent in 81% and good in 15% of the patients. Hip functions (hip rating scale of Merle d’Aubigne) were rated as excellent in 19%, very good in 22% and good in 22% of the hips. Survival correlated with preoperative Karnofsky performance status (P < 0.01) and with the absence of postoperative pulmonary complications (P < 0.01). The radiographs of the 18 patients surviving 3 months or longer showed formation of a new bony envelope around the femoral prosthetic component in 11 cases (61%) and bone remodelling of the distal femur in 12 cases (67%). These changes occurred only if no radiotherapy had been delivered to the femur (P < 0.01).

Effects of polymerization heat and monomers from acrylic cement on canine bone.

We investigated the effects of polymerization heat and toxicity of polymethylmetacrylate bone cement in the canine tibial diaphysis. Heat was studied by filling the tibias with either bone cement or bone wax contained in a monomer tight membrane pouch. Toxicity was studied by filling both tibias with cement, with the control side contained in the membrane pouch. Bone blood perfusion was measured by microsphere technic, and bone remodeling by 99mTc-methylene diphosphonate uptake and by histologic technique. In bone exposed to the combination of polymerization heat and monomer, both perfusion and remodeling were impaired. We did not find any effects of polymerization heat alone. We conclude that hot toxic chemicals from bone cement during polymerization may inhibit bone blood perfusion and remodeling, whereas heat alone seems to be of minor importance for the regenerative processes in cemented diaphyseal bone.

Carbon in medical devices

Abstract The variability of the crystalline structure of carbon allows a correspondingly wide range of possible properties. By controlling the structure of carbon through processing, as for example in the deposition of carbon in a fluidized bed, it is possible to produce deposits with unique combinations of properties. Certain of these carbons have been found to be extremely useful in prosthetic devices. The isotropic carbons deposited at relatively low temperatures (below about 1500°C), often called LTI carbons, are blocompatible in the broadest sense. They do not induce thrombosis or hemolysis or otherwise affect either the formed or molecular element of blood. They have exceptional wear and fatique properties which are not degraded by the body environment. Accordingly, these carbons are widely used in the construction of prosthetic heart valves. The modulus of elasticity of LTI carbon is unusually low for a material of such strength and falls within the limits reported for the elasticity of bone. This property, together with its ability to interface with both soft and hard tissue without eliciting a foreign body response, makes it possible to produce orthopedic joint replacements that can attach directly to bone without using polymethylmetacrylate bone cement. Using special vacuum deposition techniques, it is possible to deposit thin, impermeable isotropic carbons that mimic the structure and properties of the LTI carbon. Materials such as polymers and fabrics can be coated with such carbons and these coatings are finding use on vascular grafts, heart valve sewing rings, percutaneous access devices, and tendon and ligament replacements. Other forms of carbons, e.g. fibers and fiber composites, are currently being used clinically in orthopedic surgery. The impact of carbon on current replacement surgery and some possibilities for future applications will be described.