Introduction. While fixation on the acetabular side in resurfacing implants has been uncemented, the femoral component is usually cemented. The most common causes for early revision in hip resurfacing are femoral head and or neck fractures and aseptic loosening of the femoral component. Later failures appear to be more related to adverse soft-tissue reactions due to metal wear. Little is known about the effect of cementing techniques on the clinical outcome in hip resurfacing, since retrieval analysis of failed hip resurfacing show large variations. Two cementing techniques have dominated. The indirect low viscosity (LV) technique as for the Birmingham Hip resurfacing (BHR) system and the direct high viscosity (HV) technique as for the Articular Surface replacement (ASR) system. The ASR was withdrawn from the market in 2010 due to inferior short and midterm clinical outcome. This study presents an in vitro experiment on the cement mantle parameters and penetration into ASR resurfaced femoral heads comparing both techniques. Methods. Five sets of paried frozen cadavar femura (3 male, 2 female) were used in the study. The study was approved by ethics committee. Plastic ASR replicas (DePuy, Leeds, UK), femoral head size 47Ø were used. The LV technique was used for the right femora (Group A, fig. 1 and 3) while the HV technigue was used for the left femora (Group B. Fig 2 and 4). The speciments were cut into quadrants. An initiial visual, qualitative evaluation was followed by CT analysis of cement mantle thickness and cement penetration into bone. Results. No significant differences were seen between the four quadrants within each group. The LV technigue resulted in greater cement penetration and increased cement mantle under the top proximally. The HV technique showed less penetration and lower cement mantle. See figures 1–4. Discussion. The aim was to analyze the effect of the cementing techniques used in hip resurfacing practice. The ASR implant was chosen to improve understanding of whether the implant may have been sensitive to cementing techniques and whether an analysis of cementing with the recommended HV technique may assist in explaning the high incidence of short-term ASR revisions due to fractures. Findings for the HV technigue would indicate a superior technique according to consensus in conventional arthropalsty However, this contradicts clinical evidence on resurfacing, where LV cementation has been shown tho be superior. The superficial intergration in the HV technigue may result in only a superficial integration and subsequently suboptimal fixation to bone. To view tables/figures, please contact authors directly

During total knee arthroplasty (TKA), a tourniquet is often used intraoperatively. There are proposed benefits of tourniquet use including shorter duration of surgery, improved surgical field visualization and increased cement penetration which may improve implant longevity. However, there are also cited side effects that include increased post-operative pain, slowed recovery, skin bruising, neurovascular injury and quadriceps weakness. Randomized controlled trials have demonstrated no differences in implant longevity, however they are limited by short follow-up and small sample sizes. The objective of the current study was to evaluate the rates of revision surgery among patients undergoing cemented TKA with or without an intraoperative tourniquet and to understand the causes and risk factors for failure. A retrospective cohort study was undertaken of all patients who received a primary, cemented TKA at a high-volume arthroplasty centre from January 1999 to December 2010. Patients who underwent surgery without the use of a tourniquet and those who had a tourniquet inflated for the entirety of the case were included. The causes and timing of revision surgery were recorded and cross referenced with the Canadian Institute of Health Information Discharge Abstract Database to reduce the loss to follow-up. Survivorship analysis was performed with the use of Kaplan-Meier curves to determine overall survival rates at final follow-up. A Cox proportional hazards model was utilized to evaluate independent predictors of revision surgery. Data from 3939 cases of primary cemented TKA were available for analysis. There were 2276 (58%) cases in which a tourniquet was used for the duration of the surgery and 1663 (42%) cases in which a tourniquet was not utilized. Mean time from the primary TKA was 14.7 years (range 0 days - 22.8 years) when censored by death or revision surgery. There were 150 recorded revisions in the entire cohort, with periprosthetic joint infection (n=50) and aseptic loosening (n=41) being the most common causes for revision. The cumulative survival at final follow-up for the tourniquetless group was 93.8% at final follow-up while the cumulative survival at final follow-up for the tourniquet group was 96.9% at final follow-up. Tourniquetless surgery was an independent predictor for all-cause revision with an HR of 1.53 (95% CI 1.1, 2.1, p=0.011). Younger age and male sex were also independent factors for all cause revision. The results of the current study demonstrate higher all-cause revision rates with tourniquetless surgery in a large cohort of patients undergoing primary cemented TKA. The available literature consists of short-term trials and registry data, which have inherent limitations. Potential causes for increased revision rates in the tourniquetless group include reduced cement penetration, increased intraoperative blood loss and longer surgical. The results of the current study should be taken into consideration, alongside the known risks and benefits of tourniquet use, when considering intraoperative tourniquet use in cemented TKA

Introduction. Cement pressurisation in the distal humerus is technically difficult due to the anatomy of the humeral intramedullary (IM) cavity. Conventional cement restrictors often migrate proximally or leak, reducing the effect of pressurisation during implantation. Theoretically with a better cement bone interdigitation, the longevity of the elbow replacement can be improved. The aim of this cadaveric study was to evaluate the usefulness of a novel technique for cementation. Method. Eight paired fresh frozen cadaveric elbows were randomly allocated to conventional cementing techniques or cementing using a paediatric foley catheter as a temporary restrictor. The traditional cementing technique consisted of canal preparation using irrigation, brushing and drying prior to cementation, with no use of a cement restrictor. The new technique involved same canal preparation but prior to cementation a size 8 foley catheter was introduced and the balloon inflated to act as a temporary cement restrictor. The humeri were cut into 10mm sections. Each slice was photographed and radiographed. This dual imaging technique was used to establish the best methodology for evaluation of cement penetration. Cement penetration was calculated as a ratio of the area of intra-medullary cavity occupied by the cement. Results. There was no significant difference between the photographic and radiographic method of measuring cement penetration. Cement penetration was significantly better in the foley catheter group (P = 0.002-0.037). The maximum penetration was observed in the most distal 2-5cm. Conclusion. The foley catheter technique consistently and significantly achieved a better cement interdigitation into the cancellous bone, without leaving a void in the cement. This study has demonstrated a new cementing technique for elbow arthroplasty, utilising a paediatric foley catheter as a temporary humeral intra-medullary plug, increasing cement pressurisation and restricting proximal cement migration. Future studies using this methodology will not require supplementation of photographs with radiographic analysis

The development of more wear resistant biomaterials and better locking mechanisms for the polyethylene into the tibial base has significantly reduced polyethylene wear as a reason for revision TKA. Aseptic loosening is now the primary cause for revision TKA. Loosening can be caused by multifactorial operative issues: 1] patient selection, 2] implant alignment, 3] cementing technique. Furthermore, aseptic loosening occurs at a consistent rate over time. Increased cement penetration is important to counter bone resorption. Increasing penetration also improves cement mantle toughness leading to better mechanical integrity of the bone-cement interface and reduces bone-cement interface stress. It is important to recognise that a cleaner and drier interface does improve bone-cement penetration. Techniques to improve the process include better cement formulations, drilling sclerotic bone, devices and implant features to increase pressurization, using negative pressure suction ports in the tibia. We have extensive experience with CarboJet, a method of CO. 2. gas jet cleaning and drying. This experience was developed during 20 years of performing TKA with NO tourniquet. Schnetler et al found that the “use of a tourniquet in TKA causes a paradoxical increase in total blood loss”. So, NO tourniquet TKA is becoming the new paradigm for knee arthroplasty in reconstructive orthopaedics. Goldstein reported that pressurised carbon dioxide jet lavage resulted in a 35% increase in cement penetration depth when used vs. use of pulsatile saline lavage alone. Meneghini used this pressurised carbon dioxide system to study the influence of NO tourniquet use in TKA. He found a significant lowering of opioid consumption postoperatively. Another important factor in increasing the cement interdigitation is the influence of lipids which significantly weakens the bond at the interfaces. If motion is allowed during cementation there is additional loss of penetration and therefore fixation. The pressurised carbon dioxide delivered by the CarboJet system actually pushes the lipid, fatty marrow up and out of the bone allowing it to be suctioned or lap dried from the interface surface. The NO tourniquet technique and the use of carbon dioxide jet gas delivery to improve the bone-cement interface in TKA will be demonstrated

The development of more wear resistant biomaterials and better locking mechanisms for the polyethylene into the tibial base has significantly reduced polyethylene wear as a reason for revision TKA. Aseptic loosening is now the primary cause for revision TKA. Loosening can be caused by multifactorial operative issues: 1] patient selection, 2] implant alignment, 3] cementing technique. Furthermore, aseptic loosening occurs at a consistent rate over time. Increased cement penetration is important to counter bone resorption. Increasing penetration also improves cement mantle toughness leading to better mechanical integrity of the bone-cement interface and reduces bone-cement interface stress. It is important to recognise that a cleaner and drier interface does improve bone-cement penetration. Techniques to improve the process include better cement formulations, drilling sclerotic bone, devices and implant features to increase pressurization, using negative pressure suction ports in the tibia. We have extensive experience with CarboJet, a method of CO2 gas jet cleaning and drying. This experience was developed during 20 years of performing TKA with NO tourniquet. Schnetler et al found that the “use of a tourniquet in TKA causes a paradoxical increase in total blood loss”. So, NO tourniquet TKA is becoming the new paradigm for knee arthroplasty in reconstructive orthopaedics. Goldstein reported that pressurised carbon dioxide jet lavage resulted in a 35% increase in cement penetration depth when used versus use of pulsatile saline lavage alone. Another important factor in increasing the cement interdigitation is the influence of lipids which significantly weakens the bond at the interfaces. If motion is allowed during cementation there is additional loss of penetration and therefore fixation. The pressurised carbon dioxide delivered by the CarboJet system actually pushes the lipid, fatty marrow up and out of the bone allowing it to be suctioned or lap dried from the interface surface. The NO tourniquet technique and the use of carbon dioxide jet gas delivery to improve the bone-cement interface in TKA will be demonstrated

Introduction. The frequency of revision hip arthroplasty is increasing with the increasing life expectancy and number of individuals treated with joint replacement. Newer porous implants have been introduced which may provide better treatment options for revision arthroplasty. These may require cementation to other prosthesis components and occasionally to bone, however, there is currently no information on how these porous implants interface with cement. Materials and Methods. Cylindrical bone (control group) and porous metal probes with a diameter and height of 10mm were created and subsequently cemented in a standardized setting. These were placed under tensile and torsional loading scenarios. In this experimental study, 10 human femoral heads were used to create 20 cylindrical probes with a diameter and height of 10mm. One side was tapered to 6mm for cementation and interface evaluation. A further set of 20 probes of a porous metal implant (Trabecular Metal®) was created with the same geometry. After the probes were created and lavaged, they were cemented at the tapered surface using a medium viscosity cement at a constant cementation pressure (1.2N/mm2). The setup allowed for comparison of the porous metal/cement interface (group A) with the well-studied control group interface bone/cement (group B). The maximal interface stability of groups A and B were evaluated under tensile and rotational loading scenarios and the cement penetration was measured. Results. Group A showed a significantly decreased cement penetration under the same cementation pressure than group B, yet the interface showed a significantly more stable interface in the measured tests: larger maximum tensile force (effect size 2.7), superior maximum tensile strength (effect size 2.6), greater maximum torsional force (effect size 2.2), and higher rotational stiffness (effect size 1.5). Discussion and Conclusion. The porous metal/cement interface displays substantially more stability than does the bone/cement interface. Although these tests evaluate initial stability in an in-vitro setting, they appear promising with regard to their cemented stability. As a result, a multicomponent porous metal construct with cement interdigitation should not compromise the overall implant primary stability

Introduction. Hip resurfacing arthroplasty has gained popularity as an alternative for total hip arthroplasty. Usually, cemented fixation is used for the femoral component. However, each type of resurfacing design has its own recommended cementing technique. In a recent investigation the effect of various cementing techniques on cement mantle properties was studied. This study showed distinct differences in cement mantle volume, filling index and morphology. In this study, we investigated the effect of these cement mantle variations on the heat generation during polymerization, and its consequences in terms of thermal bone necrosis. Materials and methods. Two FEA models of resurfacing reconstructions were created based on CT-data of in vitroimplantations (Fig 1). The two models had distinct differences with respect to the amount of cement that was used for fixation. The first model was based on an implantation with low-viscosity cement, with anchoring holes drilled in the bone, and suction applied to maximize cement penetration. The second model was based on an implantation with medium viscosity cement smeared onto the bone, with no holes and no suction, leading to a thin cement layer. Thermal analyses were performed of the polymerization process, simulating three different types of bone cement: Simplex P (Stryker), CMW3 (DePuy J&J) and Osteobond (Zimmer), with distinct differences in polymerization characteristics. The polymerization kinematics were based on data reported previously. During the polymerization simulations the cement and bone temperature were monitored. Based on the local temperature and time of exposure, the occurrence of thermal bone necrosis was predicted. The total volume of necrotic bone was calculated for each case. Results and discussion. The simulations showed distinct differences between the temperature distributions in the various models. The highest temperature was found in the CMW3 model with a large cement volume (Fig. 2, Table 1), while the Osteobond model with a thin cement mantle produced the lowest temperature rise in the bone. The necrotic bone volume was highest in the CMW3 model with a large cement mantle, while the lowest volume was found in the model with a thin cement layer (Table 1). Assuming that the bone that is being penetrated by cement also is affected by thermal and toxic necrosis, more than 70% of the bone inside the resurfacing implant may become necrotic. In contrast, when using a less invasive cementing technique, thermal necrosis can be reduced to approximately 20% of the volume inside the resurfacing implant. A large zone of necrotic bone at the cement-bone interface may have serious implications for the strength and stability of resurfacing arthroplasty. Conclusion. We conclude that the cementing technique and type of cement used for fixation of a resurfacing implant can dramatically affect the viability of the femoral bone, and therefore the survival of the reconstruction. Thermal necrosis may be reduced by minimizing cement penetration, although this may also have consequences for the mechanical stability

The major benefit of TKA with tourniquet is operating in a bloodless field. A possible secondary benefit is a better cement-bone interface for fixation. The disadvantages of tourniquet use for TKA include multiple risk factors both local and systemic: Nerve damage, Altered hemodynamics with limb exsanguinations (15–20% increase in circulatory volume) and reactive hyperemia with tourniquet release (10% increase in limb size increasing soft tissue tension and secondary pain), Delay in recovery of muscle function, Increased risk of DVT with direct trauma to vessel walls and increased levels of thrombin-antithrombin complexes, A 5.3x greater risk for large venous emboli propagation and transesophageal echogenic particles, Vascular injury with higher risk in atherosclerotic, calcified arteries, Increase in wound healing disturbances, Obese patients TKA with tourniquet show impaired endothelial function and more DVTs. Our initial experience with TKA without tourniquet was in high risk patients with previous DVT or PE, multiple scarring, or compromised cardiovascular status. We have used this method on all patients for the last 14 years. The protocol includes regional anesthesia, incision and approach made with 90-degree knee flexion, meticulous hemostasis, jet lavage and filtered carbon dioxide delivered to dry and prepare bone beds for cementation, application of topical tranexamic acid and routine closure. We have encountered no differences in blood loss or transfusion rates, cement penetration/ fixation, less postoperative pain, faster straight leg raise and knee flexion gains, and fewer wound healing disturbances. We recommend TKA sans tourniquet. Let it bleed!

Purpose:. Glenoid loosening persists as a common cause of anatomic total shoulder arthroplasty (TSA) failure. Considering radiographic evidence of loosening as an endpoint, TSA has a reported survivorship of only 51.5% at 10 years. Component loosening may be related to cementation and it is postulated that poor cement penetration and heat-induced necrosis may partially be responsible. There is a growing interest among surgeons to minimize or abandon cement fixation and rely on biologic fixation to the polyethylene for long-term fixation. De Wilde et al. reported promising early clinical and radiographic results using a pegged, all-polyethylene ingrowth glenoid design implanted without cement. The goal of this study was to compare glenoid micromotion in an all-polyethylene, centrally fluted pegged glenoid using 3 cement fixation techniques. Materials and Methods:. Glenoid components (Anchor Peg Glenoid, Depuy Orthopaedics, Warsaw, IN, USA) (Figure 1) were implanted in polyurethane foam testing blocks with 3 different fixation methods (n = 5 per group). Group I glenoids were implanted with interference fit fixation with no added cement. Group II was implanted with a hybrid fixation, where only the peripheral pegs were cemented. Group III glenoids were fully cemented for implantation. Glenoid loosening was characterized according to ASTM Standard F-2028. The glenoid component and a 44 mm humeral head were mounted to a materials testing frame (858 Mini Bionix II, MTS Crop., Eden Prairie, MN, USA) with a 750N applied joint compressive force (Figure 1). A humeral head subluxation displacement of ± 0.5 mm was experimentally calculated as a value that simulates glenoid rim loading that may occur at higher load activities. For characterization of glenoid loosening, the humeral head was cycled 50,000 times along the superior-inferior glenoid axis, simulating approximately 5 years of device service. Glenoid distraction, compression, and superior-inferior glenoid migration were recorded with two differential variable reluctance transducers fixed to the glenoid prosthesis. Results:. All glenoid components completed the 50,000 cycles of humeral head translation successfully. With respect to glenoid distraction (Figure 2), interference fit fixation had significantly greater distraction compared to both hybrid and fully cemented fixation (p < 0.001). Hybrid fixation also displayed significantly higher distraction compared to fully cemented fixation (p < 0.001). In terms of glenoid compression (Figure 2), hybrid cementation had significantly greater compression compared to both interference-fit and fully cemented fixation (p < 0.001). Discussion:. This is the first biomechanics study comparing glenoid micromotion of a centrally fluted, pegged component using 3 different fixation techniques. Of all fixation methods, the fully cemented components displayed the least amount of motion in all parameters. Hybrid fixation exhibited lower distraction, higher compression, and comparable translation compared to interference-fit fixation. Results may indicate the differences in early motion and suggest little to no advantage of peripheral peg cementation over no cement with respect to initial fixation. Future studies are warranted to further evaluate interference-fit fixation as a viable option for implantation of a central fluted, all-polyethylene glenoid component