Low-viscosity Cement Research Articles

Experimental and numerical characterizations of nano-indentation responses of low viscosity and high viscosity bone cements

The present work involves experimentally determining the nano-mechanical properties (elastic modulus, hardness, plasticity index, and recovery resistance) of low viscosity (LV) and high viscosity (HV) Poly (methyl methacrylate) (PMMA) bone cement from load-displacement data obtained using Berkovich indenter, and then the effect of indentation parameters on these properties are explored through a validated three-dimensional (3D) finite element (FE) simulation. The 3D FE model includes a specimen with bilinear isotropic elastic-plastic material model. The good agreement between experimental and simulated load-displacement data for both variants of the bone cement emphasizes the applicability of the 3D FE model to predict mechanical behavior at nano scale indentation for both PMMA bone cements. The experimental and numerical analysis yield significantly higher values of elastic modulus, hardness, plasticity index, and recovery resistance for LV compared to that of HV bone cement. The experimentally determined values of elastic modulus, hardness, plasticity index, and recovery resistance for LV bone cement are 5.04±0.21 GPa, 312.33±2.84 MPa, 0.51±0.04, and 258.90±3.34 GPa, respectively, whereas the corresponding values for HV bone cement are found to be 4.45±0.29 GPa, 301.41±3.67 MPa, 0.42±0.01, and 191.63±1.66 GPa. The simulated load-displacement data concludes a remarkable results (elastic modulus, hardness, plasticity index, and recovery resistance), which suggest that the both variants of PMMA bone cement attain higher peak load along with larger hysteresis curve for increased indenter tip radius for a given indentation depth. The friction coefficient along the contact surfaces of specimen with indenter has no pronounced effect on the measurement of mechanical properties of bone cements.

Assessment of Cement Leakage in Decompressed Percutaneous Kyphoplasty.

Symptomatic osteoporotic compression fractures are commonly addressed through vertebroplasty and kyphoplasty. However, cement leakage poses a significant risk of neurological damage. We introduced "aspiration percutaneous kyphoplasty", also known as "decompressed kyphoplasty", as a method to mitigate cement leakage and conducted a comparative analysis with high viscosity cement vertebroplasty. We conducted a retrospective study that included 136 patients with single-level osteoporotic compression fractures. Among them, 70 patients underwent high viscosity cement vertebroplasty, while 66 patients received decompressed percutaneous kyphoplasty with low-viscosity cement. Comparison parameters included cement leakage rates, kyphotic angle alterations, and the occurrence of adjacent segment fractures. The overall cement leakage rate favored the decompressed kyphoplasty group (9.1% vs. 18.6%), although statistical significance was not achieved (p = 0.111). Nonetheless, the risk of intradiscal leakage significantly reduced in the decompressed kyphoplasty cohort (p = 0.011), which was particularly evident in cases lacking the preoperative cleft sign on X-rays. Kyphotic angle changes and the risk of adjacent segment collapse exhibited similar outcomes (p = 0.739 and 0.522, respectively). We concluded that decompressed kyphoplasty demonstrates efficacy in reducing intradiscal cement leakage, particularly benefiting patients without the preoperative cleft sign on X-rays by preventing intradiscal leakage.

Complication Pattern After Percutaneous Cement Discoplasty: Identification of Factors Influencing Reoperation and Length of Hospital Stay

Percutaneous cement discoplasty (PCD) was introduced to treat symptomatic vertical instability of the lumbar spine in a minimally invasive way. The aim of the present study was to analyse the complication pattern after PCD and to identify factors that predict the chance of cement leakage, reoperation and length of hospital stay (LOS). 344 patients were treated with PCD within the study period. Clinical features and complications were analysed by applying descriptive statistics, while perioperative factors predictive of cement leakage, reoperation and LOS were identified by regression models. Cement leakage rate was 30.4 % in the total cohort, however only fifth of them were symptomatic. Cement leakage itself did not have a significant influence on clinical outcome. Other complications and non-surgical adverse events were registered only in 2.0% of cases. Age, BMI, low viscosity cement, lower level of surgeon's experience and the number of operated levels were identified as risk factors of cement leakage (p<0.01, c-index=0.807). Type of procedure, Charlson comorbidity score, reoperation and non-surgical adverse events significantly increased the LOS (p<0.01). Cement leakage, early surgical practice and high BMI were risk factors for reoperation (p<0.01, c-index=0.72). In summary, PCD is a relatively safe and effective procedure for treating spinal instability due to advanced stage disc degeneration characterized by vacuum phenomenon. Cement leakage is not uncommon but only a radiologic complication without clinical consequences in most cases. On the other hand, it can increase the LOS and it is a significant risk factor for reoperation.

A new mathematical model of compressive stress-strain behaviour of low viscosity and high viscosity bone cement with different strain rates

A new mathematical model of compressive stress-strain behaviour of low viscosity (LV) and high viscosity (HV) bone cement has been proposed to capture large uniaxial deformation under constant applied strain rate by incorporating three-term power law. The modeling capacity of the proposed model has been validated using uniaxial compressive test under eight different low strain rates ranging from 1.39 × 10-4 s-1 to 3.53 × 10-2 s-1 for low viscosity and high viscosity bone cement. The well agreement between the model and experimental response suggests that the proposed model can successfully predict rate dependent deformation behavior for Poly(methyl methacrylate) (PMMA) bone cement. Additionally, the proposed model was compared with the generalized Maxwell viscoelastic model and found to be in good agreement. The comparison of compressive responses over low strain rates for LV and HV bone cement reveals their rate-dependent compressive yield stress behaviour along with a higher value of compressive yield stress of LV bone cement compared to HV bone cement. For example, at the strain rate of 1.39 × 10-4 s-1 the mean value of compressive yield stress of LV bone cement was found to be 64.46 MPa, whereas for HV bone cement it was 54.00 MPa. Moreover, the modeling of experimental compressive yield stress with the Ree-Eyring molecular theory suggests that the variation of yield stress of PMMA bone cement can be predicted using two processes Ree-Eyring theory. The proposed constitutive model might be useful to characterize large deformation behaviour with high accuracy for PMMA bone cement. Finally, both variants of PMMA bone cement also exhibit ductile-like compressive behaviour below the strain rate of 2.1 × 10-2 s-1, whereas above this threshold strain rate, brittle-like compressive failure behavior is observed.

THIRTY YEARS’ FOLLOW-UP OF THREE COMMONLY USED FEMORAL STEMS IN THE NORWEGIAN ARTHROPLASTY REGISTER: 1987–2021

The Norwegian Arthroplasty Register (NAR) started collecting data on total hip arthroplasty (THA) in 1987. Very long-term results of implants for THA are scarce. We aimed to show long-term results for the three most used femoral stems, operated from 1987.We included the uncemented Corail femoral stem (n=66,309) and the cemented Exeter stem (n=35,050) both of which are currently in frequent use. In addition, we included the Charnley stem (n=32,578, in use until 2014). To ensure comparable conditions, stems fixated with low viscosity cement and stems revised due to infections were excluded. Differences in risk of revision (all reasons and stem revisions) were assessed with Kaplan-Meier and Cox regression analyses with adjustment for possible confounding from age, sex and diagnosis (OA, other). Stem revision was defined as a revision caused by loosening of the stem, dislocation, osteolysis in the femur, or periprosthetic femur fracture, and in which the femoral component was removed or exchanged.The median and max follow-up for Corail, Exeter and Charnley were 6.3 (33.1), 8.0 (34.2) and 13.1 (34.3) respectively. Thirty years survival estimates for Corail, Exeter and Charnley stems were 88.6% (CI:85.8–90.9%), 86.7% (83.7–89.2%) and 87.1% (85.4–88.5%) respectively with stem revision as endpoint, and 56.1% (CI:53.1–59.1%), 73.3% (70.5–76.1%) and 80.2% (78.4–82.0%) with all THA revisions as endpoint. Compared to the Corail, the Exeter (HRR=1.3, CI:1.2–1.4) and the Charnley (HRR=1.9, CI:1.7–2.1) had a significant higher risk of stem revision. Women 75 years and older had better results with the cemented stems. Analyses accounting for competing risk from other causes of revision did not alter the findings.The uncemented Corail stem performed well in terms of stem revisions for stem-related revision causes compared to two frequently used cemented stems with very long follow-up. The differences between the three stems were small.

Low viscosity versus high viscosity PMMA bone cement for total joint arthroplasty: Influence of glass transition temperature, residual monomer content, transmittance of chemical functional groups, and crystallinity index on quasi-static flexural strength

The commercially available low viscosity (LV) PMMA bone cement has higher mechanical properties than high viscosity (HV) PMMA bone cement. However, the influence of glass transition temperature, residual monomer content, transmittance of chemical functional groups and crystallinity index on flexural strength is yet to be unveiled. The present study is aimed to investigate the influence of glass transition temperature, residual monomer content, transmittance of chemical functional groups and crystallinity index that contributed to the higher flexural strength of LV bone cement compared to HV bone cement. The thermal behavior analysis indicated higher glass transition temperature and residual content for LV bone cement (87.5 ± 1.80 °C and 15.56±0.62%, respectively) as compared to HV bone cement (81±2.64 °C and 13.69±0.38%, respectively). Moreover, the chemical parameters such as relatively low residual monomer content computed using Raman spectroscopy and low transmittance of chemical functional groups found in FTIR spectra for LV bone cement imply better flexural strength compared to that of HV bone cement. Results indicated the crystallinity index was higher for LV (42.78 ± 0.54%) bone cement than HV bone cement (36.41 ± 0.18%). The difference in flexural strength between LV and HV bone cements governed by glass transition temperature, crystallinity index, residual monomer content and transmittance of chemical functional groups assists in the improvement and applications of PMMA bone cement.

Clinical application of targeted sealing with high viscosity bone cement and secondary injection of low viscosity bone cement in vertebroplasty

To observe the clinical efficacy of targeted sealing with high viscosity bone cement and secondary injection of low viscosity bone cement in the treatment of OVCFs patients with the fracture lines involved vertebral body margin. The elderly patients who underwent vertebroplasty for osteoporotic vertebral compression fractures from January 2019 to September 2021 were selected as the screening objects. Through relevant standards and further CT examination, 56 patients with fracture lines involving the anterior wall or upper and lower endplates of the vertebral body were selected for the study. There were 21 males and 35 females, aged from 67 to 89 years old with an average of (76.58±9.68) years. All 56 patients underwent secondary injection of bone cement during operation. Only a small amount of high viscosity cement was targeted to seal the edge of the vertebral body for the first time, and low viscosity cement was injected to the vertebral bodies during second bolus with well-distributed. The operation time, bone cement volume and bone cement leakage were recorded, and the pain relief was evaluated by visual analogue scale (VAS). All patients were followed up for more than 3 months and the surgeries were successfully complete. The operation time was (50.41±10.30) min and the bone cement volume was (3.64±1.29) ml. The preoperative VAS was (7.21±2.41) points, which decreased significantly to (2.81±0.97) points 3 days after operation(P<0.05). Among the 56 patients, 2 cases(3.57%) had bone cement leakage, 1 case leaked to the paravertebral vein, and 1 case slightly bulged to the paravertebral through the crack when plugging the vertebral crack. Both patients had no obvious clinical symptoms. In vertebroplasty surgery, targeted sealing of high viscosity bone cement and secondary injection of low viscosity bone cement can reduce intraoperative bone cement leakage and improve the safety of operation.

Rectifying an Excessive Vibration Issue in Shallow Foundation with Permeation Grouting: A Case Study

Large vibrating machines are integral part of industrial facility. This paper describes the case example of excessive vibration, encountered in one of the machine foundations in such facility, as well as the corresponding rectification works. This vibrating machine was built on shallow foundation sitting on compacted sand fill layer; the foundation self-weight is more than eight (8) times of the equipment weight. The block foundation dimension is about 7.0 x 1.7 x 1.7 m3. The vibrating machine frequency (which sits above the foundation) is 450 rpm, with a relatively large impulsive cyclic load. In this paper, firstly, the potential root cause of this vibration issue is explored. Thereafter, considerations for the rectification works are described; in this case, a permeation grouting technique, using low-viscosity cement grout is chosen. The work method for this ground improvement works, including the completion criteria are described. Post-improvement vibration measurement indicates that the measured vibration is within the accepted vibration limit, indicating a successful improvement work.

High-viscosity versus low-viscosity cement for the treatment of vertebral compression fractures: A meta-analysis of randomized controlled trials.

High viscosity cement (HVC) and low viscosity cement (LVC) have been used to treat osteoporotic vertebral compression fractures (OVCFs). Our study was to assess the safety and efficacy of HVC and LVC in treating OVCFs. We searched the electronic database for randomized controlled trials of HVC and LVC to treat OVCFs. Random-effects model was performed to pool the outcomes about operation time, visual analogue scale (VAS), bone cement injection volume, oswestry disability index (ODI), bone cement leakage and adjacent vertebral fractures. Twelve randomized trials were included in the meta-analysis. The 2 groups had similar changes in terms of bone cement injection volume, ODI and adjacent vertebral fractures. The HVC group showed shorter operation time and better VAS score improvement. The bone cement leakage rate of the HVC group was significantly better than LVC group (P < .00001).According to the location of bone cement leakage, in the leakages of the veins (P < .00001), the intervertebral disc (P < .00001), the paravertebral area (P = .003) and the intraspinal space (P = .03), the HVC group were significantly better than the LVC group. In terms of bone cement injection volume, ODI and adjacent vertebral fractures, the 2 group are equivalent. HVC had a shorter operation time, lower bone cement leakage rate and better VAS score improvement, compared with LVC.

Cement augmentation for treatment of high to mid-thoracic osteoporotic compression fractures, high-viscosity cement percutaneous vertebroplasty versus balloon kyphoplasty

Whilst the majority of the literature suggests that balloon kyphoplasty (BKP) can relieve pain associated with vertebral compression fractures (VCFs), evidence of high-viscosity cement (HVC) vertebroplasty (VP) or low viscosity cement (LVC) BKP for the treatment of VCFs at the levels of high and mid-thoracic vertebrae remains limited. The purpose of this study was to identify the different outcomes between HVC VP and LVC BKP used to repair high (T4–6) and mid (T7–9)-thoracic VCFs. A total of 114 patients with painful collapsed single-level vertebrae at high to mid-thoracic level who had undergone HVC VP or LVC BKP at a single tertiary medical center was reviewed retrospectively. All patients were divided into the HVC VP group (n = 72) and the LVC BKP group (n = 42). Clinical outcomes including demographic data and visual analogue scale (VAS) were compared. Radiographic data were collected preoperatively, postoperatively, and at final follow-up. More volume (ml) of cement injection was seen in the LVC BKP group (4.40 vs. 3.66, p < 0.001). The operation time (minutes) of the HVC VP group was significantly less than that of the LVC BKP group (33.34 vs. 39.05, p = 0.011). Leakage rate of cement was also fewer in the HVC VP group (26/72 vs. 27/42, p = 0.004). Compared with preoperative data, the VAS was improved after surgery in both groups. The LVC BKP group corrected more middle vertebral body height and local kyphosis angle than the HVC VP group. The outcomes of LVC BKP were not superior to that of HVC VP. HVC VP might be a good alternative to LVC BKP in the treatment of osteoporotic VCFs in high to mid-thoracic spine.

Leveraging Coiled Tubing Conveyance in an Integrated and Rigless Abandonment and Perforation Workflow

Summary In Ecuador, shutoff of an underperforming interval through plug and abandonment (P&amp;A) and perforation of a new interval are traditionally completed with a combination of wireline (WL) and tubing conveyance. An alternative method using enhanced coiled tubing (CT) is presented here; it enables a rigless and efficient workflow that leverages real-time downhole data for on-the-fly optimization. The new workflow relies on CT-conveyed technologies without requiring any additional conveyance methods. CT delivered four different services to start the abandonment by anchoring a 7-in. cast-iron bridge plug (CIBP), complete the abandonment with a low-viscosity cement plug, simulate wellbore dynamics during nitrogen pumping to generate the required underbalanced conditions for perforating, and perforate with a 40-ft ballistic payload of 4 1/2-in. guns. Coupled with real-time downhole telemetry, the enhanced CT workflow provided critical downhole conditions, including fluid levels, accurate depth placement and control, bridge plug setting confirmation, underbalanced conditions, perforating head activation and detonation, and postperforation inflow monitoring. Compared with traditional methods, the enhanced CT workflow introduces several benefits toward completing P&amp;A of old intervals and perforation of new ones. These benefits include enabling a rigless workover (WO) intervention, eliminating the need and cost of a WO rig, reducing operational duration by 13%, and potentially reducing asset footprint and field crews by 95 and 70%, respectively. Elimination of a WO rig reduces environmental impact and the number of personnel on location (i.e., risk). The workflow also extends the reach and efficiency of the service in horizontal wells, enables underbalanced perforation, and delivers actionable real-time downhole data. These data elevate traditional P&amp;A workflows and create a step change in efficiency. First, they allow tracking key downhole parameters that help guarantee a reliable operation of each of the tools and services. Second, they provide insights into the actual downhole conditions throughout the intervention to enable the operator and the field crews to make on-the-fly decisions to deliver a safe and optimal service. Those decisions may include fine-tuning the prescribed treatment or extending the scope of the intervention by leveraging the CT’s pump-through capabilities to maximize well performance and meet, or exceed, the operator’s objectives. The innovative combination of real-time telemetry with abandonment and perforating technologies proved a step change in operational efficiency and range, fueled by the quantity and quality of data recorded during the operation. This case study also marks the first documented perforation with 4 1/2-in. guns with fiber-optic real-time downhole telemetry. Furthermore, the integrated, rigless solution provides operators with an opportunity to extend their WO activity pipeline and free up their WO fleet for other activities.

No Difference in Revision Rate Between Low Viscosity and High Viscosity Cement Used in Primary Total Knee Arthroplasty

BackgroundLoosening remains one of the most common reasons for revision total knee arthroplasty (TKA). Cement viscosity has a potential role in reducing revision rates for loosening. The aim of this study was to assess the outcome for loosening of the 5 most used cemented knee prostheses by constraint type, based on the cement viscosity type used. MethodsThere were 214,708 TKA procedures performed between 1999 and 2020 for a diagnosis of osteoarthritis using the 5 most commonly used minimally stabilized, posterior stabilized, and medial pivot design cemented tibial components. Only procedures with a cemented tibial component were included. Outcomes for two different cement viscosities, 140,060 high viscosity and 74,648 low viscosity cement, were compared for each fixation type within each of the three stability groups. ResultsThere was no difference in a risk of all-cause revision when high viscosity cement was used compared to low viscosity cement for minimally stabilized prostheses (hazards ratio [HR] 1.07 [95% CI 0.99-1.15], P = .09), posterior stabilized prostheses (HR 1.03 [95% CI 0.95-1.11], P = .53), and medial pivot design prostheses (HR 1.06 [95% CI 0.80-1.41], P = .67). No difference was observed between cement viscosity types for any of the prosthesis constraint types when aseptic loosening was assessed. ConclusionsWe found no difference in the risk of revision for any reason, or for loosening, with cement viscosity for the most commonly used minimally stabilized, posterior stabilized, and medial pivot TKA. The role of cement viscosity in the risk of TKA revision remains unclear and further research is required. Level of EvidenceLevel III Retrospective comparative study.

High- versus low-viscosity cement vertebroplasty and kyphoplasty for osteoporotic vertebral compression fracture: a meta-analysis.

To compare high- versus low-viscosity bone cement on the clinical outcomes and complications in patients with Osteoporotic vertebral compression fractures (OVCFs) who underwent percutaneous vertebroplasty (PVP) or percutaneous kyphoplasty (PKP). PubMed, Embase, and the Cochrane Library were searched for papers published from inception up to February 2021 for potentially eligible studies comparing high- versus low-viscosity cement for PVP/PKP. The outcomes were the leakage rate, visual analog scale (VAS), and Oswestry Disability Index (ODI). Eight studies (558 patients; 279 in each group) were included. The meta-analysis showed that the leakage rate was lower with high-viscosity cement than with low-viscosity cement (OR = 0.23, 95%CI 0.14-0.39, P < 0.001; I2 = 43.5%, Pheterogeneity = 0.088); similar results were observed specifically for the disk space, paravertebral space, and peripheral vein, but there were no differences regarding the epidural space and intraspinal space. The VAS was decreased more significantly with high-viscosity cement than with low-viscosity cement (WMD = - 0.21, 95%CI - 0.38, - 0.04, P = 0.015; I2 = 0.0%, Pheterogeneity = 0.565). Regarding the ODI, there was no difference between high- and low-viscosity cement (WMD = - 0.88, 95%CI - 3.06, 1.29, P = 0.426; I2 = 78.3%, Pheterogeneity < 0.001). There were lower cement leakage rates in PVP/PKP with high-viscosity bone cement than low-viscosity bone cement. The two groups have similar results in ODI, but the VAS scores favor high-viscosity bone cement. Therefore, the administration of high-viscosity bone cement in PVP/ PKP could be a potential option for improving the complications of leakage in OVCFs, while the clinical efficacy of relieving pain is not certain.

Survival of Prosthodontic Restorations Luted with Resin-Based versus Composite-Based Cements: Retrospective Cohort Study.

The purpose of this study was to evaluate clinical performance, survival, and complications of indirect composite inlays, onlays, and overlays on posterior teeth. Digital records of 282 patients treated between 2014 and 2018 were accessed and analyzed retrospectively. The included patients received 469 composite restorations luted with seven different resin-based types of cement, i.e., Filtek Ultimate Flow, Enamel Plus, Relyx Ultimate, Harvard Premium Flow, Relyx Unicem, Filtek Bulk Fill Flowable, and Filtek Ultimate. The restorations had been clinically and radiographically evaluated annually. The mechanical and clinical complications, e.g., debonding, fracture, and secondary caries, were evaluated and recorded. The examined restorations exhibited a high survival rate (84.9%), and failure was found in only 71 cases. Fracture was the most common cause (n = 36), followed by prosthetic work release (n = 19) and secondary caries (n = 16). There was a statistically significant difference between failure and cement material (Sig. < 0.001); the composite-based cements (87.2%) had a high survival rate compared to the resin-based cement (72.7%). Similarly, the cements with high viscosity (90.2%) had significantly higher survival rates than the low-viscosity cements (78.9%). Moreover, onlays showed higher longevity compared to overlays (Sig. = 0.007), and patients aged under 55 years showed less complications (Sig. = 0.036). Indirect composite restoration was a successful solution to tooth structure loss. The material of the cementation is an important part of the success. Higher survival rate was found in our study when the fixation materials with high viscosity were used, thus suggesting using these materials with indirect restorations. Composite-based cements had significantly higher survival rate than resin-based cements.

Overview of research work of Prof. Chu on two medical devices

Surgical procedures are relatively common and procedures for broken bones often involve intramedullary nailing to repair the bone and keep it stable. However, there are challenges associated with the process and Professor Woeichyn Chu, who is a distinguished professor based within the Department of Biomedical Engineering at the National Yang Ming Chiao Tung University in Taiwan, is developing a medical device to help surgeons overcome these challenges, benefiting patients and clinicians. The device is called iMET (intra-medullary endo-transilluminating) and came about after Woeichyn Chu spoke with his brother, Dr William Chu, General Orthopedic Department, Cheng Hsin General Hospital, Taiwan, about some of the challenges relating to intramedullary nailing which led the brothers to begin working together to develop a medical device to help target distal locking holes in intramedullary nailing procedures. The iMET device that the brothers are developing is designed to improve target aiming accuracy and reduce dose absorption concerns. In the process, it will save significant time, effort and money. As well as benefiting patients and clinicians, iMET also reduces X-ray fluoroscopy time, which has health benefits for all involved. Woeichyn Chu and his brother are also developing a device called iKypho, which applies negative pressure during bone cement injection in percutaneous vertebroplasty surgeries. iKypho reduces bone cment leakage risks when using low viscosity cement and reducing the costs associated with high viscosity bone cement.

Loosening of tibia baseplates after total knee arthroplasty: Evaluation of pull-out strength of tibia baseplate-cement Interface

BackgroundAseptic loosening is reported as the leading cause of revision total knee arthroplasty on the Australian National Joint Replacement Registry. Loosening of cemented tibial baseplates has been correlated with type of cement used, cementing technique, and cement contamination with biological material. The aim of this study was to evaluate the effect of cementing application and techniques including surface contamination and cement viscosity on fixation strength of tibia baseplates/cement interface. MethodsMechanical assessment of the fixation strength of tibia baseplates/cement interface was tested using a pull-out test on a material testing system. Different tibial baseplate design, cementing techniques, cement viscosity and contamination of the implant/cement interface with bone marrow were assessed to determine if they influenced force required to disrupt the cement/implant interface (pull-out strength). FindingsThe model with contamination of the cement prosthesis interface demonstrated a lower pull-out strength (p < 0.001). The model with the keel and baseplate cemented showed a higher pull-out strength compared to cementing the baseplate alone (p < 0.001). The use of low-viscosity cement resulted in a significantly higher failure force (p = 0.002) compared to high-viscosity cement when cementing the baseplate alone. InterpretationsBiomechanical testing demonstrated improved fixation with cementing the tibial keel and keeping surfaces free from contamination during the cementation process.

CORR Insights®: Does the Risk of Death Within 48 Hours of Hip Hemiarthroplasty Differ Between Patients Treated with Cemented and Cementless Implants? A Meta-analysis of Large, National Registries.

CORR Insights®: Does the Risk of Death Within 48 Hours of Hip Hemiarthroplasty Differ Between Patients Treated with Cemented and Cementless Implants? A Meta-analysis of Large, National Registries.

Comparison of high- and low-viscosity cement percutaneous vertebroplasty with manipulative reduction for the treatment of Kümmell's disease: A retrospective cohort study.

To compare the clinical outcomes and cement leakage rate between high-viscosity and low-viscosity cement percutaneous vertebroplasty (PVP) with manipulative reduction in the treatment of Kümmell's disease (KD). PVP using high-viscosity cement (Group H) or low-viscosity cement (Group L) with manipulative reduction was compared in 86 KD patients. Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), vertebral height, kyphosis angle and complications were evaluated and compared preoperative, one day postoperative, and at final follow-up. The VAS score, ODI score, mean anterior and middle vertebral height variation significantly improved in both groups postoperatively. However, there was no significant difference between the two groups considering the above results preoperative and postoperative. Significantly less cement leakage (13.6%) and shorter operative time (35.6 ± 5.1 min) were observed in Group H when compared with Group L (45.2% and 41.1 ± 5.3 min) (p< 0.05). The clinical outcomes and radiologic findings of PVP with manipulative reduction was not influenced by cement viscosity. However, high cement viscosity PVP was found to be significant less cement leakage and shorter operative time.

A comparison of 2 cementing techniques in hip resurfacing using human femoral heads.

Hip resurfacing remains a valid option in young male patients. The creation of the optimum cement mantle aids fixation of the femoral component. If the cement mantle is too thick the prosthesis can remain proud leading to early failure or if it penetrates too far into the femoral head, it may cause osteonecrosis. 18 of 96 femoral heads collected from patients undergoing total hip arthroplasty were matched for their surface porosity. They were randomly allocated into 2 different cementing groups. Group 1 had the traditional bolus of cement technique, while group 2 had a modified cementing technique (swirl) where the inside of the femoral component was lined with an even layer of low viscosity cement. The traditional bolus technique had significantly greater cement mantle thickness in 3 of 4 zones of penetration (p = 0.002), greater and larger air bubble formation (6 of 9 in bolus technique vs. 1 in 9 in swirl technique, p = 0.05) and more incomplete cement mantles compared with the swirl technique. There was no relationship to femoral head porosity. The swirl technique should be used to cement the femoral component in hip resurfacing. Long-term clinical studies would conform if this translates into increased survivorship of the femoral component.

High-Viscosity Versus a Lower-Viscosity Cement Penetration at Dough Phase In Vivo in Primary Total Knee Arthroplasty

BackgroundPrevious studies have shown that the depth of cement penetration and the presence of radiolucent lines (RLLs) correspond with the risk of aseptic loosening in total knee arthroplasty, while others have found a correlation between the viscosity of the cement and the depth of cement penetration. We compared cement marketed as high-viscosity cement (HVC) with one marketed by the same manufacturer as low-viscosity cement (LVC). We hypothesized that no significant difference would be found in depth of penetration or presence of RLLs between the two cohorts. MethodsThe HVC (n = 50) and LVC cohorts (n = 50) were gathered from two sequential series of primary total knee arthroplasties using the same implants and cementing techniques. Depth of cement penetration and presence of RLL were measured in four tibial zones and were compared between cohorts. ResultsThere were no cases of aseptic loosening in either cohort at a mean of 29 months. Mean maximum cement penetration in 3 of the 4 zones was >3 mm with both cements. There was no significant difference in maximum penetration in any zone between the two cements. There were fewer tibial radiolucencies with HVC than LVC. ConclusionThese findings suggest that the marketing description of HVC or LVC is not necessarily a factor in cement penetration. The term high viscosity should not be used as a descriptor of cement that reaches dough phase more quickly, but rather cement that has a higher viscosity at its dough phase when it is typically applied.