髋关节置换术用丙烯酸骨水泥性能评价的关注点

经查阅髋关节置换术用丙烯酸骨水泥的相关文献、相关技术标准、产品指导原则等,认为对骨水泥的评价主要涉及骨水泥的单体残留、凝固行为、机械性能和生物相容性等产品性能。生产企业应加强骨水泥产品的基础研究能力,制定科学的技术指标和试验方法,以确保产品的安全有效性,同时也可为注册申报提供充分的支持性数据。     

Antibiotic‐loaded Bone Cement as Prophylaxis in Total Joint Replacement

One of its most serious complications associated with arthroplasty is the development of infections. Although its prevalence is only between 0.5% and 3%, in some cases it can lead to death. Therefore, an important challenge in joint surgery is the prevention of infections when an arthroplasty is performed. The use of antibiotic‐loaded cements could be a suitable tool due to numerous advantages. The main advantage of the use of antibiotic loading into bone cement derives directly from antibiotic release in the effect site, allowing achievement of high concentrations at the site of action, and minimal or no systemic toxicity. This route of administration was first described by Buchholz and Engelbrecht. In the case of infection treatment, this is an established method and its good results have been confirmed. However, its role in infection prevention, and, therefore, the use of these systems in clinical practice, has proved controversial because of the uncertainty about the development of possible antibiotic resistance after prolonged exposure time, their effectiveness, the cost of the systems, toxicity and loosening of mechanical properties. This review discusses all these topics, focusing on effectiveness and safety, antibiotic decisions, cement type, mixing method, release kinetics and future perspectives. The final objective is to provide the orthopaedic surgeons the right information in their clinical practice based on current evidence.     

Bioactivity of Ceftazidime and Fluconazole Included in Polymethyl Methacrylate Bone Cement for Use in Arthroplasty

Background

The microorganisms that most frequently cause prosthetic joint infection are methicillin-resistant Staphylococcus aureus and gram-negative aerobic bacillus. Studies have documented the efficacy of mixing antibiotics with polymethyl methacrylate, but that of antifungal drugs has not received much attention. The objective of this in vitro study was to characterize the elution profile and bioactivity of ceftazidime and fluconazole when incorporated into bone cement in proportions intended for prophylaxis and treatment of bone infections.

Tibial Component Migration After Total Knee Arthroplasty With High-Viscosity Bone Cement

BackgroundHigh-viscosity (HV) bone cements have been formulated to offer potentially advantageous handling characteristics. However, alteration in the handling characteristics could influence implant fixation and survival. The primary objective of this study was to use radiostereometric analysis after total knee arthroplasty to assess the migration of the Triathlon tibial component fixed with HV cement (Simplex HV).MethodsTwenty-three patients were followed for two years with radiostereometric analysis examinations at 6 visits. Migration was compared with published thresholds and with a control group from a previously published study from the same center using the same implants fixed with a medium viscosity cement. Inducible displacement was assessed, and Oxford 12 Knee Scores and satisfaction were recorded.ResultsMean maximum total point motion migration reaching 0.40 mm (SD 0.16) at one year, and 0.41mm (SD 0.17) at two years, demonstrating a pattern of stable fixation, below published thresholds of acceptable migration, and not significantly different from the control group. One implant had continuous migration between 1 and 2 years but was clinically asymptomatic. Mean maximum total point motion inducible displacement measured at least one year postoperatively was 0.3 mm (SD 0.12). Mean Oxford 12 Knee Scores improved from 19 (SD 7) preoperatively to 42 (SD 8) 2 years postoperatively.ConclusionsThe use of HV cement demonstrated an acceptable pattern of migration at 2 years, indicating low risk for aseptic loosening.     

Routine Use of Antibiotic Laden Bone Cement for Primary Total Knee Arthroplasty: Impact on Infecting Microbial Patterns and Resistance Profiles

Antibiotic-laden bone cement (ALBC) is used in primary arthroplasties throughout Europe. In North America, ALBC is only FDA approved for revision arthroplasty after periprosthetic joint infection (PJI). No article has evaluated whether infecting microbial profile and resistance has changed with the introduction of ALBC. We hypothesized that prophylactic use of ALBC in primary total knee arthroplasty (TKA) has not had a significant impact on infecting pathogens, and antibiotic resistance profiles. A retrospective cohort analysis was conducted of all PJI patients undergoing primary TKA and total hip arthroplasty (THA) between January 2000 and January 2009. No significant change in the patterns of infecting PJI pathogens, and no notable increase in percentage resistance was found among organisms grown from patients with PJI that had received prophylactic antibiotic-loaded cement in their primary joint arthroplasty. Early findings suggest that routine prophylactic use of ALBC has not led to changes in infecting pathogen profile, nor has led to the emergence of antimicrobial resistance at our institution.     

Fracture Toughness of Acrylic PMMA Bone Cement: A Mini-Review

BackgroundAcrylic PMMA bone cement is an essential component in cemented implants and formed the cement-bone and cement-implant interfaces. The information on the fracture parameters of PMMA bone cement would be decisive for all doctors, researchers, and orthopaedic surgeons.PurposeThis review aims to indicate the parameters responsible for the variation in the fracture toughness of PMMA bone cement. This mini-review also points out some limitations of the earlier published research article, which can be added in the future analysis and can be helpful to get the more realistic data of the fracture parameters of PMMA bone cement.ConclusionDifferent mixing techniques, storage medium, temperature, loading conditions, frequency and environment, cement viscosity, type of specimen, and the ASTM standards (shape, size, and geometry), constituents, loading rate, and cement porosity were the critical parameters to affect the fracture toughness of PMMA bone cement. This study will also be helpful to increase the structural integrity of PMMA bone cement and the cemented implant.     

微波消融联合骨水泥、锁定钢板内固定治疗长骨干转移癌

目的探讨原位微波消融联合骨水泥、锁定钢板内固定治疗四肢长骨干转移癌的疗效。方法回顾性分析2010年3月~2018年6月我科收治的17例四肢长骨干转移癌患者的临床资料,其中病理性骨折3例,均采用原位微波消融、病灶刮除后联合骨水泥填充、锁定钢板内固定治疗,手术部位:股骨7例,肱骨6例,胫骨4例。结果所有患者均顺利完成手术,无术中并发症。所有患者术后均获得随访,随访时间5~27个月。术后3月VAS评分、MSTS评分、KPS评分较术前明显改善,差异均有统计学意义(P<0.05)。术后14个月出现右股骨钢板断裂并骨折1例,术后20个月出现左肱骨转移灶复发1例。随访期间死亡12例,存活5例。术后半年、1年及2年生存率分别为94.1%,60.8%及8.9%。结论采用原位微波消融联合骨水泥填充、锁定钢板内固定治疗四肢长骨干转移癌,可以降低肿瘤局部复发率,缓解疼痛,恢复患肢功能,改善患者生活质量。     

Comparative Study of Antibiotic Elution Profiles From Alternative Formulations of Polymethylmethacrylate Bone Cement

BackgroundPolymethylmethacrylate (PMMA) bone cement is commonly used in orthopedic surgery for implant fixation and local antibiotic delivery following surgical debridement. The incidence of nephrotoxicity necessitates the balance of antiinfective properties with the potential for toxicity. Thus, understanding antibiotic elution characteristics of different PMMA formulations is essential. We sought to address this by assessing elution of vancomycin, daptomycin, and tobramycin from Palacos LV (Palacos), Stryker Surgical Simplex P (Simplex), BIOMET Cobalt HV (Cobalt), and Zimmer Biomet Bone Cement R (Zimmer) radiopaque bone cements.MethodsAntibiotics were mixed with each cement formulation, and molds were used to produce beads of cement. Beads were incubated in phosphate-buffered saline at 37°C, and antibiotic elution was measured daily for 10 days with vancomycin and 5 days with daptomycin and tobramycin. Active antibiotic was quantified by serial dilution and comparison to the minimum inhibitory concentration.ResultsThe elution profiles of Simplex were significantly lower than all other cements with all antibiotics (P < .00093). Palacos exhibited a significantly higher vancomycin elution profile than all other cements (P < .00001). The difference in daptomycin elution profiles for Cobalt and Palacos was not significant (P > .43), but both were significantly higher than Zimmer (P < .0006).ConclusionOverall, Stryker Surgical Simplex P exhibits a significantly lower elution profile than all other cements tested. In general, Palacos LV exhibits an increased elution profile compared with other cements. This elution information may assist the surgeon in choosing different cement formulations for the local delivery of antibiotics.     

Combined Autograft and Bone Cement for Painful Chondroblastoma: A Case Report

Chondroblastomas of the talus can lead to joint collapse and are often treated using curettage and bone grafting. In the present report, we describe the case of a 19-year-old female with a large chondroblastoma of the talus associated with a secondary aneurysmal cyst. We treated the large cartilage lesion, which involved most of the talus, with an iliac bone graft combined with bone cement to fill the large bone defect and preserve the subchondral bone of the articular surface of the dome of the talus.     

The Bone and Joint Decade 2000-2010: An update

Background?Fracture and low bone mineral density both have strong predictive value for future fractures. The risk of future fractures can be reduced by medi-cal treatment if patients with osteoporosis are identified, for example by screening fracture patients for low bone mineral density. We suggest that these screening rou-tines be organized at orthopedics departments and we report our experience with such a screening system.

Patients and methods?We screened all patients between 50–75 years of age with a wrist, vertebral, prox-imal humerus, or hip fracture visiting our orthopedics department by measuring bone mineral density (BMD) using DEXA scans. After diagnosis, the patients were referred to their primary care physician for treatment.

Results?Between November 1, 2002, and October 31, 2003, 239 patients were investigated and only 13% had normal BMD values. 45% of the patients were diagnosed with osteopenia and 42% with osteoporosis.

Interpretation?Screening of fracture patients who visit an orthopedics department appears to be an effec-tive way of identifying individuals with low bone min-eral density. The screening routines can be organized as an osteoporosis team consisting of a doctor, a nurse and a secretary at each department. Today, these patients are largely undetected and untreated—at least in our region. In our series, only 13 patients had been DEXA-scanned and were treated by antiresorptive drugs at the time of fracture.??     

Risk Stratified Usage of Antibiotic-Loaded Bone Cement for Primary Total Knee Arthroplasty: Short Term Infection Outcomes With a Standardized Cement Protocol

Efficacy of antibiotic cement (ALBC) in primary knee arthroplasty (pTKA) has been debated. The study’s purpose was to examine efficacy of ALBC versus plain cement (PBC) in preventing infection in high-risk patients undergoing pTKA. 3292 consecutive pTKAs were divided into three cohorts: (1) patients receiving only PBC, (2) patients receiving only ALBC, and (3) only high-risk patients receiving ALBC. Cohorts’ infections were compared. The 30-day infection rates for cohorts 1, 2, 3 were 0.29%, 0.20%, and 0.13% respectively. 6-month rates were 0.39%, 0.54% and 0.38%. 1-year rates were 0.78%, 0.61%, and 0.64%. Differences in infection rates at all time intervals were not statistically significant. The study supports that even judicious risk-stratified usage of ALBC may not confer added benefit in decreasing infection at one year.     

Effects of Pore Size on the Osteoconductivity and Mechanical Properties of Calcium Phosphate Cement in a Rabbit Model

Calcium phosphate cement (CPC) porous scaffold is widely used as a suitable bone substitute to repair bone defect, but the optimal pore size is unclear yet. The current study aimed to evaluate the effect of different pore sizes on the processing of bone formation in repairing segmental bone defect of rabbits using CPC porous scaffolds. Three kinds of CPC porous scaffolds with 5 mm diameters and 12 mm length were prepared with the same porosity but different pore sizes (Group A: 200–300 µm, Group B: 300–450 µm, Group C: 450–600 µm, respectively). Twelve millimeter segmental bone defects were created in the middle of the radius bone and filled with different kinds of CPC cylindrical scaffolds. After 4, 12, and 24 weeks, alkaline phosphatase (ALP), histological assessment, and mechanical properties evaluation were performed in all three groups. After 4 weeks, ALP activity increased in all groups but was highest in Group A with smallest pore size. The new bone formation within the scaffolds was not obvious in all groups. After 12 weeks, the new bone formation within the scaffolds was obvious in each group and highest in Group A. At 24 weeks, no significant difference in new bone formation was observed among different groups. Besides the osteoconductive effect, Group A with smallest pore size also had the best mechanical properties in vivo at 12 weeks. We demonstrate that pore size has a significant effect on the osteoconductivity and mechanical properties of calcium phosphate cement porous scaffold in vivo. Small pore size favors the bone formation in the early stage and may be more suitable for repairing segmental bone defect in vivo.     

Selected Heat-Sensitive Antibiotics Are Not Inactivated During Polymethylmethacrylate Curing and Can Be Used in Cement Spacers for Periprosthetic Joint Infection

Background

Antibiotic use in polymethylmethacrylate (PMMA) spacers has historically been limited to those which are “heat-stable” and thus retain their antimicrobial properties after exposure to the high temperatures which occur during PMMA curing.

经皮后凸成形术并发骨水泥渗漏的类型及临床意义

目的探讨经皮后凸成形术（percutaneous kyphoplasty,PKP）治疗骨质疏松性椎体压缩骨折 （osteoporoticvertebral body compression fracture,OVCF）并发骨水泥渗漏的类型及临床意义。方法回顾性分析北京友谊医院2005年6月至2009年6月期间收治的123例PKP治疗0VCF患者的临床资料,手术椎体共402个,记录骨水泥渗漏部位及骨水泥渗漏给患者带来的临床症状以及术前、术后3d、术后6个月随访时的疼痛视觉模拟评分,以评估疼痛缓解程度;相关数据统计运用SPSS13．0统计软件包,进行配对t检验。P〈0．05为差异有统计学意义,P〈0．01为差异有显著统计学意义。结果本组手术均一次性成功,术后发生渗漏36例52个椎体,渗漏率12．94％。按解剖位置对椎体外的局部骨水泥渗漏共分7型。临床随访6～30个月,平均16个月。除1例骨水泥渗漏至椎管内硬膜外患者术后出现同侧下肢疼痛及肌力减退外,其余患者均无明显临床表现。结论a）经皮后凸成形术治疗骨质疏松性椎体压缩骨折是一种有效、安全的微创手术,能够迅速地改善临床症状。b）按解剖位置对椎体外的局部骨水泥渗漏共分7型。穿刺针道渗漏和椎间盘渗漏发生率最高,但患者无明显临床症状,不影响手术疗效;椎管内渗漏发生率最低,但可产生脊髓神经症状等极少数严重后果。所以仍需尽量避免渗漏的发生。     

Antibacterial efficacy of a new gentamicin‐coating for cementless prostheses compared to gentamicin‐loaded bone cement

Cementless prostheses are increasingly popular but require alternative prophylactic measures than the use of antibiotic‐loaded bone cements. Here, we determine the 24‐h growth inhibition of gentamicin‐releasing coatings from grit‐blasted and porous‐coated titanium alloys, and compare their antibacterial efficacies and gentamicin release‐profiles to those of a commercially available gentamicin‐loaded bone cement. Antibacterial efficacy increased with increasing doses of gentamicin in the coating and loading with 1.0 and 0.1 mg gentamicin/cm² on both grit‐blasted and porous‐coated samples yielded comparable efficacy to gentamicin‐loaded bone cement. The coating had a higher burst release than bone cement, and also inhibited growth of gentamicin‐resistant strains. Antibacterial efficacy of the gentamicin coatings disappeared after 4 days, while gentamicin‐loaded bone cement exhibited efficacy over at least 7 days. Shut‐down after 4 days of gentamicin‐release from coatings is advantageous over the low‐dosage tail‐release from bone cements, as it minimizing risk of inducing antibiotic‐resistant strains. Both gentamicin‐loaded cement discs and gentamicin‐coated titanium coupons were able to kill gentamicin‐sensitive and ‐resistant bacteria in a simulated prothesis‐related interfacial gap. In conclusion, the gentamicin coating provided similar antibacterial properties to those seen by gentamicin‐loaded bone cement, implying protection of a prosthesis from being colonized by peri‐operatively introduced bacteria in cementless total joint arthroplasty. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1654–1661, 2011     

Short‐term Follow‐up of Antibiotic‐loaded Articulating Cement Spacers in Two‐stage Revision of Infected Total Knee Arthroplasty: A Case Series

Objective

Infection of total knee arthroplasty (TKA) is a rare but devastating complication. Two‐stage revision is an effective treatment for late infected TKA. This study aimed to assess the short‐term results of two‐stage revision using articulating antibiotic‐loaded spacers.

Methods

Twenty‐five patients (10 men and 15 women) were diagnosed with late infections after TKA and treated with two‐stage revision from April 2006 to August 2010; 19 of these patients had TKA for osteoarthritis and 6 for rheumatoid arthritis. Median age was 64.9 (range, 56–83) years. In the first‐stage surgery, the prosthesis and all bone cement was removed. After thorough debridement, bone cement with vancomycin and tobramycin was put into a die cavity and made into temporary femoral and tibial spacers, respectively. In the cases of good knee range of motion, the temporary spacers were affixed to the bone surface using the same antibiotic bone cement. In the second surgery, gentamycin Refobacin Bone Cement with vancomycin was used to fix the prosthesis. After two‐stage revision, patients were followed up clinically and radiologically at 1, 3, and 6 months, and then annually. Knee Society Score (KSS), knee function score, knee pain score, and knee range of motion (ROM) were assessed.

Results

Among the group, all spacers were easily removed, and bone defect degree showed no obvious change compared with pre‐implant, 24 (96%) patients had been debrided once, and 1 patient had been debrided twice before reimplant prosthesis. Mean follow‐up was 64.2 (range, 52–89) months. There was no infection recurrence at final follow‐up. Compared with preoperative data, the KSS (66 [59, 71], 83 [80, 88] vs 46 [43, 57], P < 0.01), knee function score (43 [42, 49], 78 [73, 82] vs 32 [25, 37], P < 0.01), knee pain score (34 [33, 37], 42 [40, 45] vs 18 [16, 23], P < 0.01), and knee ROM (92° [86°, 96°], 94° [90°, 98°] vs 78° [67°, 86°], P < 0.01) were all improved during follow‐up and at final visit. Three patients experienced complications in the interval period: one case had knee dislocation, one had knee instability, and one had a chip in the femoral component of the spacer.

Conclusion

Using articulating antibiotic‐loaded spacers showed benefits for treating infected TKA in selected patients. No infection recurrence was observed during follow‐up.

     

Hollow Notched K‐Wires for Bone Drilling With Through‐Tool Cooling

Kirschner wire (K‐wire) is a common tool in clinical orthopedic surgery for bone fracture fixation. A significant amount of heat is generated in bone drilling using K‐wires, causing bone thermal necrosis and osteonecrosis. To minimize the temperature rise, a hollow notched K‐wire in a modified surgical hand drill with through‐tool cooling was developed to study the bone temperature, debris evacuation, and material removal rate. The hollow notched K‐wire was fabricated by grinding and micro‐milling on a stainless steel tube. Bone drilling tests were conducted to evaluate its performance against the solid K‐wires. Results showed that compared with solid K‐wires, hollow notched K‐wire drilling without cooling reduced the peak bone temperature rise, thrust force, and torque by 42%, 59%, and 62% correspondingly. The through‐tool compressed air reduced the peak bone temperature rise by 48% with the forced air convection and better debris evacuation. The through‐tool water cooling decreased the bone temperature by only 26% due to accumulation and blockage of bone debris in the groove and channel. This study demonstrated the benefit of using the hollow notched K‐wire with through‐tool compressed air to prevent the bone thermal necrosis. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2297–2306, 2019     

Cement Loaded With High-Dose Gentamicin and Clindamycin Reduces the Risk of Subsequent Infection After One-Stage Hip or Knee Arthroplasty Exchange for Periprosthetic Infection: A Preliminary Study

BackgroundThe use of antibiotic-loaded acrylic cement for treating periprosthetic joint infections remains controversial. We hypothesized that the raw rate of surgical site infection (SSI) is lower after using cement loaded with high-dose gentamicin and clindamycin than after using cement loaded with standard-dose gentamicin for implant fixation during 1-stage hip and knee revision arthroplasty for infection.MethodsOne hundred seventy-one continuous patients operated by 2 experienced surgeons during a 2-year period were included in the study. All patients were followed for 24 months. The primary endpoint was the raw rate of SSI after 2 years of follow-up time.ResultsThe raw rate of SSI after 2 years of follow-up time was significantly lower in the study group (13%) than in the control group (26%) (P = .03) with an odds ratio of 0.42 (P = .03). These SSIs were new infections rather than a recurrence/persistence of the initial infection.ConclusionThe cement used in the study group significantly reduced the risk of SSI relative to the cement used in the control group. Routine use of this high-dose dual antibiotic-loaded cement can be considered during 1-stage knee or hip revision arthroplasty for infection.     

The Effect of Tourniquet Use and Sterile Carbon Dioxide Gas Bone Preparation on Cement Penetration in Primary Total Knee Arthroplasty

BackgroundTourniquetless total knee arthroplasty (TKA) is experiencing resurgence in popularity due to potential pain control benefits. Furthermore, optimal cement technique and implant fixation remain paramount to long-term cemented TKA success, as aseptic loosening continues to be a leading cause of revision. The purpose of this study is to determine how tourniquet use and/or novel bone preparation using sterile, compressed carbon dioxide (CO₂) gas affected cement penetration in TKA.MethodsA retrospective review was performed on 303 consecutive primary TKAs with the same implant in 3 groups: (1) a tourniquet without sterile CO₂ compressed gas used for bone preparation, (2) no tourniquet with CO₂ gas, and (3) tourniquet use and CO₂ gas bone preparation. Cement penetration was measured on radiographs by two independent, blinded raters across 7 zones defined by the Knee Society Radiographic Evaluation System.ResultsThe 3 groups did not differ on age, body mass index, or gender (P ≥ .1). Cement penetration was greater in 6 of 7 zones with significantly greater cement penetration in 3 zones (tibial anteroposterior zone 2, femoral lateral zones 3A and 3P) in groups that utilized CO₂ gas bone preparation compared to the tourniquet only group (P ≤ .039).ConclusionBone prepared with CO₂ gas showed significantly more cement penetration in 3 zones with greater cancellous bone. The results suggest that use of CO₂ gas bone preparation may achieve greater cement penetration than using a tourniquet with lavage only.     

Isthmus‐guided Cortical Bone Trajectory for Pedicle Screw Insertion

Herein is described cortical bone trajectory (CBT), a new path for pedicle screw insertion for lumbar vertebral fusion. Because the points of insertion are under the end of the inferior articular process, and because the screws are inserted toward the lateral side, there is less soft tissue development than with the conventional technique; the CBT technique therefore enables less invasive surgery than the conventional technique. However, it has some drawbacks. For example, in the original CBT approach, the points of insertion are in the vicinity of the end of the inferior articular process. Because this joint has been destroyed in many patients who have indications for intervertebral fusion surgery, it is sometimes difficult to use it as a reference point for screw insertion location. With severe lateral slippage, the screw insertion site can become significantly dislocated sideways, with possible resultant damaging to the spinal canal and/or nerve root. The CBT technique here involved inserting the screws while keeping clear of the intervertebral foramen with the assistance of side view X‐ray fluoroscopy and using the end of the inferior articular process and the isthmus as points of reference for screw location.