The Influence of Citrus Pectin and Polyacrylamide Modified with Plant-Derived Additives on the Properties of α-TCP-Based Bone Cements.

Materials based on highly reactive α-tricalcium phosphate (α-TCP) powder were developed and evaluated. Furthermore, the impact of different polymeric additives, such as citrus pectin or polyacrylamide (PAAM) modified with sago starch, neem flower, or rambutan peel, on the physiochemical and biological properties of the developed materials was assessed. The addition of modified PAAM shortened the setting process of bone cements and decreased their compressive strength. On the other hand, the addition of citrus pectin significantly enhanced the mechanical strength of the material from 4.46 to 7.15 MPa. The improved mechanical properties of the bone cement containing citrus pectin were attributed to the better homogenization of cementitious pastes and pectin cross-linking by Ca2+ ions. In vitro tests performed on L929 cells showed that 10% extracts from α-TCP cements modified with pectin are more cytocompatible than control cements without any additives. Cements containing PAAM with plant-derived modifiers show some degree of cytotoxicity for the highly concentrated 10% extracts, but for diluted extracts, cytotoxicity was reduced, as shown by a resazurin reduction test and live/dead staining. All the developed bone substitutes exhibited in vitro bioactivity, making them promising candidates for further biological studies. This research underscores the advantageous properties of the obtained biomaterials and paves the way for subsequent more advanced in vitro and in vivo investigations.

In Vivo Investigation of 3D-Printed Calcium Magnesium Phosphate Wedges in Partial Load Defects.

Bone substitutes are ideally biocompatible, osteoconductive, degradable and defect-specific and provide mechanical stability. Magnesium phosphate cements (MPCs) offer high initial stability and faster degradation compared to the well-researched calcium phosphate cements (CPCs). Calcium magnesium phosphate cements (CMPCs) should combine the properties of both and have so far shown promising results. The present study aimed to investigate and compare the degradation and osseointegration behavior of 3D powder-printed wedges of CMPC and MPC in vivo. The wedges were post-treated with phosphoric acid (CMPC) and diammonium hydrogen phosphate (MPC) and implanted in a partially loaded defect model in the proximal rabbit tibia. The evaluation included clinical, in vivo µ-CT and X-ray examinations, histology, energy dispersive X-ray analysis (EDX) and scanning electron microscopy (SEM) for up to 30 weeks. SEM analysis revealed a zone of unreacted material in the MPC, indicating the need to optimize the manufacturing and post-treatment process. However, all materials showed excellent biocompatibility and mechanical stability. After 24 weeks, they were almost completely degraded. The slower degradation rate of the CMPC corresponded more favorably to the bone growth rate compared to the MPC. Due to the promising results of the CMPC in this study, it should be further investigated, for example in defect models with higher load.

Multi-center study of use of the Exeter stem in Japan: a 10-year follow-up report.

PURPOSE: Since the introduction of the Exeter stem for clinical use in Japan in 1996, the number of stems used has continued to rise owing to its favorable results. We investigated the outcomes of patients who had previously undergone total hip arthroplasty with the Exeter stem in Japan with a 10-year + follow-up period. METHODS: This retrospective cohort study used clinical and radiographic data of 682 cases of primary total hip arthroplasty performed using the Exeter stem. RESULTS: The mean postoperative follow-up period was 13.3 years. Femoral-side revision was required in 14 hips, with no cases of aseptic stem loosening-associated revision observed. Kaplan-Meier survival analysis predicted 97.3% 15-year survival when revision for any reason was used as the endpoint. CONCLUSION: The obtained findings suggested the excellent long-term stability of the Exeter stem for primary total hip arthroplasty in Japan.

Bone mineral density of the incus body and long process in patients with chronic otitis media and its relationship with functional outcome in type II tympanoplasty.

BACKGROUND: Inflammatory conditions such as chronic otitis media (COM) can cause irreversible impairments in the microarchitecture and functions of the incus, which subsequently leads to conductive hearing loss. OBJECTIVES: To investigate bone mineral density (BMD) of the incus body (IB) and long process (ILP) on preoperative temporal CT in COM patients with and without incudo-stapedial joint discontinuity (ISJD), and also to determine the association between BMD values and the postoperative air-bone gap (ABG) in the ISJD group. MATERIAL AND METHODS: The mean IB density (IBD)/occipital bone density (OBD) and ILP density (ILPD)/OBD values were compared between the patients with and without ISJD. The correlation between ABG gain and preoperative incus density values was assessed in the ISJD group. RESULTS: The mean IBD/OBD and ILPD/OBD values were significantly higher in patients with intact ISJ. There was a moderate positive correlation between postoperative ABG gain and ILPD/OBD values in the ISJD group. CONCLUSION AND SIGNIFICANCE: The decrease in BMD of the incus may involve ILP as well as IB in patients with ISJD caused by ILP lysis in COM. A higher preoperative ILPD/OBD was correlated with a higher postoperative ABG gain in COM patients with ISJD.

Cemented vs. Cementless Fixation in Primary Knee Replacement: A Narrative Review.

Knee osteoarthritis (OA) is one of the leading causes of disability around the globe. Osteoarthritis is mainly considered a disease affecting the elderly. However, more and more studies show that sports overuse, obesity, or congenital disorders can initiate a pathologic cascade that leads to OA changes in the younger population. Nevertheless, OA mostly affects the elderly, and with increasing life expectancy, the disease will develop in more and more individuals. To date, the golden standard in the treatment of the end-stage of the disease is total joint replacement (TJR), which restores painless knee motion and function. One of the weakest elements in TJR is its bonding with the bone, which can be achieved by bonding material, such as poly methyl-methacrylate (PMMA), or by cementless fixation supported by bone ingrowth onto the endoprosthesis surface. Each technique has its advantages; however, the most important factor is the revision rate and survivor time. In the past, numerous articles were published regarding TJR revision rate, but no consensus has been established yet. In this review, we focused on a comparison of cemented and cementless total knee replacement surgeries. We introduced PICO rules, including population, intervention, comparison and outcomes of TJR in a PubMed search. We identified 783 articles published between 2010 and 2023, out of which we included 14 in our review. Our review reveals that there is no universally prescribed approach to fixate knee prostheses. The determination of the most suitable method necessitates an individualized decision-making process involving the active participation and informed consent of each patient.

Octacalcium phosphate phase forming cements as an injectable bone substitute materials: Preparation and in vitro structural study.

In the realm of regenerating damaged or degenerated bones through minimally invasive techniques, injectable materials have emerged as exceptionally promising. Among these, calcium phosphate bone cements (CPCs) have garnered significant interest due to their remarkable bioactivity, setting it apart from non-degradable alternatives such as polymethyl methacrylate cements. α-Tricalcium phosphate (α-TCP) is a widely used solid phase component in CPCs. It can transform into calcium-deficient hydroxyapatite (CDHAp) when it comes in contact with water. In this study, we aimed to create an injectable, self-setting bone cement using low-temperature synthesized α-TCP powder as a single precursor of the powder phase. We found that changes in the pH of the liquid phase (pH 6.0, pH 6.2, pH 7.0 and pH 7.4) significantly altered the cement's setting, handling, and mechanical properties. The formation of the octacalcium phosphate (OCP) phase was identified in our study, which positively affects the osteoblastic cell response. Hardened OCP-forming bone cements prepared using a liquid phase with pH 7.0 and 7.4 showed better osteogenic cell attachment and proliferation than those prepared with pH 6.0 and 6.2. Our study suggests that changes in the pH of the liquid phase can significantly affect the properties of α-TCP-based bone cement, and the presence of the OCP phase is crucial for optimal cement performance.

Malignant Chest Wall Tumors: Complex Defects and Their Management-A Review of 181 Cases.

BACKGROUND: Chest wall tumors are a heterogeneous group of tumors that are managed by surgeons from diverse specialties. Due to their rarity, there is no consensus on their diagnosis and management. MATERIALS: This retrospective, descriptive analysis includes patients with malignant chest wall tumors undergoing chest wall resection. Tumors were classified as primary, secondary, and metastatic tumors. The analysis includes clinicopathological characteristics, resection-reconstruction profile, and relapse patterns. RESULTS: A total of 181 patients underwent chest wall resection between 1999 and 2020. In primary tumors (69%), the majority were soft tissue tumors (59%). In secondary tumors, the majority were from the breast (45%) and lung (42%). Twenty-five percent of patients received neoadjuvant chemotherapy, and 98% of patients underwent R0 resection. Soft tissue, skeletal + soft tissue, and extended resections were performed in 45%, 70%, and 28% of patients, respectively. The majority of patients (60%) underwent rib resections, and a median of 3.5 ribs were resected. The mean defect size was 24 cm2. Soft tissue reconstruction was performed in 40% of patients, mostly with latissimus dorsi flaps. Rigid reconstruction was performed in 57% of patients, and 18% underwent mesh-bone cement sandwich technique reconstruction. Adjuvant radiotherapy and chemotherapy were given to 29% and 39% of patients, respectively. CONCLUSIONS: This is one of the largest single-institutional experiences on malignant chest wall tumors. The results highlight varied tumor spectra and multimodality approaches for optimal functional and survival outcomes. In limited resource setting, surgery, including reconstructive expertise, is very crucial.

Evidence-Based Data Regarding the Use of Antibiotic-loaded Cement in Hip Arthroplasty. A bibliometric analysis of 50 years / Datos basados en la evidencia sobre el uso de cemento con antibióticos en la artroplastia de cadera. Análisis blbliométrico de 50 años

Introduction: The use of antibiotic-loaded cement is an intraoperative tool that has demonstrated potential benefits in hip arthroplasty. However, the global landscape of research on this topic remains unknown. The objective of this study was to analyze the scientific growth, characteristics, and metrics of global and historical research on the use of antibiotic-loaded cement in hip arthroplasty. Material and methods: A cross-sectional bibliometric study was conducted using Scopus as the data source. Results: A total of 523 documents published between 1973 and 2023 were selected. 89.9% (n=470) of the production consisted of original articles, with 11.85% being multi-center. 84.1% of the authors have published a single article, followed by 10.3% who have published two articles. Research has predominantly focused on adults or the elderly, with an emphasis on outcome evaluation (notably reoperation), assessing various antibiotic agents, and frequently employing retrospective designs. Conclusions: There has been a sustained increase in research on the use of antibiotic-loaded cement in hip arthroplasty over the last 50 years. The research trend has shifted towards the evaluation of adult or elderly patients, exploration of antimicrobial agents, techniques, and health outcomes, primarily using observational and retrospective designs. An emerging research-focus is the study of hip arthroplasty in rheumatoid arthritis patients. (AU)

Introducción: El uso de cemento cargado con antibiótico, es una herramienta intraoperatoria que ha demostrado potenciales beneficios en la artroplastia de cadera. Sin embargo, se desconoce el panorama global de la investigación sobre este tópico. El objetivo de este estudio fue analizar el crecimiento científico, características y métricas de la investigación global e histórica sobre el uso de cemento cargado con antibiótico en artroplastia de cadera. Material y métodos: Estudio bibliométrico de corte transversal, que utilizó como fuente de datos la base Scopus. Resultados: Se seleccionaron 523 documentos publicados entre 1973 y 2023. El 89,9% (n=470) de la producción consistió en artículos originales, siendo el 11,85% multicéntricos. El 84,1% de los autores han publicado un único artículo, seguido de un 10,3% que han publicado dos artículos. La investigación se ha centrado predominantemente en adultos o ancianos, con énfasis en la evaluación de resultados (especialmente la reoperación), evaluando diversos agentes antibióticos y empleando con frecuencia diseños retrospectivos. Conclusiones: En los últimos 50 años se ha producido un aumento sostenido de la investigación sobre el uso de cemento cargado con antibióticos en la artroplastia de cadera. La tendencia de la investigación se ha desplazado hacia la evaluación de pacientes adultos o ancianos, la exploración de los agentes antimicrobianos, las técnicas y los resultados sanitarios, utilizando principalmente diseños observacionales y retrospectivos. Un nuevo foco de investigación es el estudio de la artroplastia de cadera en pacientes con artritis reumatoide. (AU)

Effect of Atmospheric Pressure Plasma Jet Treatments on Magnesium Phosphate Cements: Performance, Characterization, and Applications.

Atmospheric pressure plasma treatments are nowadays gaining importance to improve the performance of biomaterials in the orthopedic field. Among those, magnesium phosphate-based cements (MPCs) have recently shown attractive features as bone repair materials. The effect of plasma treatments on such cements, which has not been investigated so far, could represent an innovative strategy to modify MPCs' physicochemical properties and to tune their interaction with cells. MPCs were prepared and treated for 5, 7.5, and 10 min with a cold atmospheric pressure plasma jet. The reactive nitrogen and oxygen species formed during the treatment were characterized. The surfaces of MPCs were studied in terms of the phase composition, morphology, and topography. After a preliminary test in simulated body fluid, the proliferation, adhesion, and osteogenic differentiation of human mesenchymal cells on MPCs were assessed. Plasma treatments induce modifications in the relative amounts of struvite, newberyite, and farringtonite on the surfaces on MPCs in a time-dependent fashion. Nonetheless, all investigated scaffolds show a good biocompatibility and cell adhesion, also supporting osteogenic differentiation of mesenchymal cells.

Novel Double Hybrid-Type Bone Cements Based on Calcium Phosphates, Chitosan and Citrus Pectin.

In this work, the influence of the liquid phase composition on the physicochemical properties of double hybrid-type bone substitutes was investigated. The solid phase of obtained biomicroconcretes was composed of highly reactive α-tricalcium phosphate powder (α-TCP) and hybrid hydroxyapatite/chitosan granules (HA/CTS). Various combinations of disodium phosphate (Na2HPO4) solution and citrus pectin gel were used as liquid phases. The novelty of this study is the development of double-hybrid materials with a dual setting system. The double hybrid phenomenon is due to the interactions between polycationic polymer (chitosan in hybrid granules) and polyanionic polymer (citrus pectin). The chemical and phase composition (FTIR, XRD), setting times (Gillmore needles), injectability, mechanical strength, microstructure (SEM) and chemical stability in vitro were studied. The setting times of obtained materials ranged from 4.5 to 30.5 min for initial and from 7.5 to 55.5 min for final setting times. The compressive strength varied from 5.75 to 13.24 MPa. By incorporating citrus pectin into the liquid phase of the materials, not only did it enhance their physicochemical properties, but it also resulted in the development of fully injectable materials featuring a dual setting system. It has been shown that the properties of materials can be controlled by using the appropriate ratio of citrus pectin in the liquid phase.

Nonlinear viscoelastic model for time-dependent mechanical characterization of PMMA acrylic bone cements.

Acrylic bone cement materials are widely used in prosthetic implants, orthopaedics and others trauma surgery. From the mechanical constitutive behaviour viewpoint, experimental analyses have provided ample evidence that such materials exhibit time-dependent properties. In this context, this work addresses the formulation of a nonlinear viscoelastic model for the behaviour of PMMA bone cements under compressive creep loading. Relying upon experimental data available for four PMMA bone cement types, a nonlinear Burgers-like rheological model is formulated and related parameters calibrated for the mechanical description of the time-dependent behaviour of these materials under isothermal conditions and one dimensional setting. The proposed model reveals relevant in reproducing both instantaneous and delayed properties of studied PMMA bone cements.

Comparative Analysis of the Tibial Component Migration After Cemented and Uncemented Total Knee Arthroplasty with a Hydroxyapatite Coating in Two, Five, and Ten Years: A Meta-Analysis.

Objective This study evaluated and compared the tibial component migration in cemented and uncemented total knee arthroplasty (TKA) with no hydroxyapatite coating 2, 5, and 10 years after surgery. Methods This meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) based on PubMed and MeSH database queries from June to July 2022. Results The meta-analysis included eight randomized clinical studies evaluating 668 knees undergoing TKA. The maximum total point motion (MTPM) in cemented TKAs was higher in 5 years, with a mean value of 0.67 mm (95% confidence interval [CI], 0.52 to 0.87). Uncemented TKAs also presented higher mean MTPM in 5 years (1 mm; 95% CI, 0.82 to 1.22). Uncemented coated ATKs had a higher mean MTPM in 10 years (1.30 mm; 95% CI, 0.70 to 2.39). MTPM was statistically similar in the short- and long-term for cemented and uncemented techniques, with a standardized mean difference of -0.65 (95% CI, -1.65 to 0.35). Conclusion Tibial component migration in TKA was statistically similar at 2, 5, and 10 years in cemented and uncemented techniques, either with or without coating. However, due to the scarce literature, further studies are required with a longer follow-up time.

Comparative Analysis of the Tibial Component Migration After Cemented and Uncemented Total Knee Arthroplasty with a Hydroxyapatite Coating in Two, Five, and Ten Years: A Meta-Analysis / Análise comparativa da migração do componente tibial da artroplastia total do joelho cimentada versus não cimentada versus não cimentada com revestimento de hidroxapatita por dois, cinco e dez anos: uma metanálise

Abstract Objective This study evaluated and compared the tibial component migration in cemented and uncemented total knee arthroplasty (TKA) with no hydroxyapatite coating 2, 5, and 10 years after surgery. Methods This meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) based on PubMed and MeSH database queries from June to July 2022. Results The meta-analysis included eight randomized clinical studies evaluating 668 knees undergoing TKA. The maximum total point motion (MTPM) in cemented TKAs was higher in 5 years, with a mean value of 0.67 mm (95% confidence interval [CI], 0.52 to 0.87). Uncemented TKAs also presented higher mean MTPM in 5 years (1 mm; 95% CI, 0.82 to 1.22). Uncemented coated ATKs had a higher mean MTPM in 10 years (1.30 mm; 95% CI, 0.70 to 2.39). MTPM was statistically similar in the short- and long-term for cemented and uncemented techniques, with a standardized mean difference of -0.65 (95% CI, -1.65 to 0.35). Conclusion Tibial component migration in TKA was statistically similar at 2, 5, and 10 years in cemented and uncemented techniques, either with or without coating. However, due to the scarce literature, further studies are required with a longer follow-up time.

Resumo Objetivo Avaliar e comparar a migração obtida pelo componente tibial na Artroplastia Total de Joelho (ATJ) cimentada, não cimentada sem revestimento e não cimentada com revestimento de hidroxapatita aos 2, 5 e 10 anos pós operatório. Métodos Esta metanálise foi conduzida de acordo com o Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Foi realizada busca a partir das bases de dados PubMed e MeSH no período de junho a julho de 2022. Resultados Oito ensaios clínicos randomizados foram incluídos. Um total de 668 joelhos submetidos a ATJ foram avaliados. Observou-se que a média de Maximun Total Point Motion (MTPM) nas ATJ cimentada foi maior em experimentos com cinco anos com média de 0,67 mm (IC95% - 0,52 a 0,87), as ATJ não cimentadas com revestimento de hidroxapatita também obtiveram maior média neste período (1mm; IC95% - 0,82 a 1,22). Em ATJ não cimentada sem revestimento o maior MTPM médio ocorreu no período de 10 anos (1,30mm; IC95% - 0,70 a 2,39). O MTPM foi estatisticamente semelhante no curto e longo prazo ao comparar as técnicas cimentada e não cimentada, com diferença média padronizada -0,65 (IC95%, -1,65 a 0,35). Conclusão A migração obtida pelo componente tibial na artroplastia total de joelho (ATJ) foi estatisticamente semelhante em 2, 5 e 10 anos ao comparar as técnicas cimentada e não cimentada (com e sem revestimento). Entretanto, devido ao pequeno número de artigos existentes, são necessários mais estudos clínicos sobre tais técnicas e com maior tempo de acompanhamento.

Prosthetic Joint Infections: Biofilm Formation, Management, and the Potential of Mesoporous Bioactive Glass as a New Treatment Option.

Infection of prosthetic joints is one of the biggest challenges to a successful replacement of the joint after a total joint arthroplasty. Such infections are caused by bacterial colonies that are difficult to treat by systemic delivery of antibiotics. Local delivery of antibiotics can prove to be the solution to such a devastating outcome that impacts patients' health and ability to regain function in their joints as well as costs the healthcare system millions of dollars every year. This review will discuss prosthetic joint infections in detail with a focus on the development, management, and diagnosis of the infections. Surgeons often opt to use polymethacrylate cement locally to deliver antibiotics; however, due to the rapid release of antibiotics, non-biodegradability, and high chance of reinfection, the search for alternatives is in high demand. One of the most researched alternatives to current treatments is the use of biodegradable and highly compatible bioactive glass. The novelty of this review lies in its focus on mesoporous bioactive glass as a potential alternative to current treatments for prosthetic joint infection. Mesoporous bioactive glass is the focus of this review because it has a higher capacity to deliver biomolecules, stimulate bone growth, and treat infections after prosthetic joint replacement surgeries. The review also examines different synthesis methods, compositions, and properties of mesoporous bioactive glass, highlighting its potential as a biomaterial for the treatment of joint infections.

Ready-To-Use and Rapidly Biodegradable Magnesium Phosphate Bone Cement: In Vivo Evaluation in Sheep.

In clinical practice, hydroxyapatite (HA) cements for bone defect treatment are frequently prepared by mixing a powder component and a liquid component shortly before implantation in the operation theater, which is time-consuming and error-prone. In addition, HA cements are only slightly resorbed, that is, cement residues can still be found in the bone years after implantation. Here, these challenges are addressed by a prefabricated magnesium phosphate cement paste based on glycerol, which is ready-to-use and can be directly applied during surgery. By using a trimodal particle size distribution (PSD), the paste is readily injectable and exhibits a compressive strength of 9-14 MPa after setting. Struvite (MgNH4 PO4 ·6H2 O), dittmarite (MgNH4 PO4 ·H2 O), farringtonite (Mg3 (PO4 )2 ), and newberyite (MgHPO4 ·3H2 O) are the mineral phases present in the set cement. The paste developed here features a promising degradation of 37% after four months in an ovine implantation model, with 25% of the implant area being newly formed bone. It is concluded that the novel prefabricated paste improves application during surgery, has a suitable degradation rate, and supports bone regeneration.

Is there a Difference in Interfragmentary Compression Strength Between Fully or Partially Threaded Screws? Results of an Experimental Biomechanical Pilot Study.

Objective This study assessed differences between fully- and partially-threaded screws in the initial interfragmentary compression strength. Our hypothesis was that there would be an increased loss in initial compression strength with the partially-threaded screw. Methods A 45-degree oblique fracture line was created in artificial bone samples. The first group (FULL, n = 6) was fixed using a 3.5-mm fully-threaded lag screw, while the second group (PARTIAL, n = 6) used a 3.5-mm partially-threaded lag screw. Torsional stiffness for both rotational directions were evaluated. The groups were compared based on biomechanical parameters: angle-moment-stiffness, time-moment-stiffness, maximal torsional moment (failure load), and calibrated compression force based on pressure sensor measurement. Results After loss of one PARTIAL sample, no statistically significant differences in calibrated compression force measurement were observed between both groups: [median (interquartile range)] FULL: 112.6 (10.5) N versus PARTIAL: 106.9 (7.1) N, Mann-Whitney U-test: p = 0.8). In addition, after exclusion of 3 samples for mechanical testing (FULL n = 5, PARTIAL n = 4), no statistically significant differences were observed between FULL and PARTIAL constructs in angle-moment-stiffness, time-moment-stiffness, nor maximum torsional moment (failure load). Conclusion There is no apparent difference in the initial compression strength (compression force or construct stiffness or failure load) achieved using either fully- or partially-threaded screws in this biomechanical model in high-density artificial bone. Fully-threaded screws could, therefore, be more useful in diaphyseal fracture treatment. Further research on the impact in softer osteoporotic, or metaphyseal bone models, and to evaluate the clinical significance is required.

Handmade spacers for two-stage exchange at the hip.

OBJECTIVE: Two-stage exchange with implantation of a temporary spacer is the gold standard treatment for chronic periprosthetic joint infection of the hip. This article describes a simple and safe technique for handmade spacers at the hip. INDICATION: Periprosthetic joint infection of the hip. Septic arthritis of the native joint. CONTRAINDICATIONS: Known allergy against components of polymethylmethacrylate bone cements. Inadequate compliance for two-stage exchange. Patient unfit to undergo two-stage exchange. Bony defect situation at the acetabulum impeding stable reduction of the spacer. Bone loss at the femur jeopardizing stable fixation of the stem. Soft tissue damage with need for plastic temporary vacuum-assisted wound closure (VAC) therapy. SURGICAL TECHNIQUE: Tailoring bone cement with antibiotics. Preparation of a metal endoskeleton. Molding of spacer stem and head by hand. Customizing spacer off-sets to bony anatomy and soft tissue tension. Implantation assuring rotational stability at the femur with a bone cement collar. Confirmation of correct position by intraoperative radiography. POSTOPERATIVE MANAGEMENT: Restricted weight-bearing. Range of motion as possible. Reimplantation after successful treatment of infection.

Handmade articulating spacer for two-stage exchange at the knee.

OBJECTIVE: Two-stage exchange with implantation of a temporary spacer is considered gold standard treatment for chronic periprosthetic joint infection of the knee. This article describes a simple and safe technique for handmade articulating spacers at the knee. INDICATION: Chronic or relapsing periprosthetic joint infection of the knee. RELATIVE CONTRAINDICATIONS: Known allergy against components of polymethylmethacrylate (PMMA) bone cements or admixed antibiotics. Inadequate compliance for two-stage exchange. Patient not able to undergo two-stage exchange. Bony defect situation at the tibia or femur leading to collateral ligament insufficiency. Soft tissue damage with need for plastic temporary vacuum-assisted wound closure (VAC) therapy. SURGICAL TECHNIQUE: Removal of the prosthesis, thorough debridement of necrotic and granulation tissue, tailoring bone cement with antibiotics. Preparation of a tibial and femoral stem. Customizing the tibial and femoral articulating spacer components to bony anatomy and soft tissue tension. Confirmation of correct position by intraoperative radiography. POSTOPERATIVE MANAGEMENT: Protection of the spacer with an external brace. Restricted weight-bearing. Passive range of motion as possible. Intravenous-followed by oral antibiotics. Reimplantation after successful treatment of infection.

A design of a targeted puncture trajectory applied to unilateral extrapedicular percutaneous vertebroplasty.

OBJECTIVE: In this study, we introduced a design of a targeted puncture trajectory applied to unilateral extrapedicular percutaneous vertebroplasty. METHODS: 62 individuals with osteoporotic vertebral compression fractures (OVCF) were included in this research at the Tongling People's Hospital, from January 2019 to December 2020. Percutaneous Vertebroplasty (PVP) was performed on all patients using a targeted unilateral extrapedicular puncture technique guided by G-arm fluoroscopy. The operating time, volume and dispersion of bone cement, and cement leak were all evaluated. The oswestry disability index(ODI) and the visual analog scale (VAS) were used to assess pain relief and quality of life (QOL). RESULTS: The targeted puncture trajectory for unilateral extrapedicular PVP was used to successfully treat a total of 62 fractured vertebrae without any apparent clinical issues. In comparison to their equivalent preoperative values, the VAS and ODI values after surgery were considerably lower (P < 0.01). The bone cement not only could be across the midline of the targeted vertebrae but also appeared in both the bilateral pedicle and the center projection region on the anteroposterior X-ray film, according to radiologic results in all injured vertebrae. There were 3 cases of leakage at the anterior border of the vertebral body and 2 cases of leakage into the intervertebral region without significant clinical manifestations. Furthermore, no bone cement leaked into the vessels or spinal canal. CONCLUSION: The design of the targeted puncture trajectory used in unilateral extrapedicular PVP not only ensures that the bone cement injector transcends the midline of the vertebral body, but it also improves the accuracy of the injector arriving at the contralateral pedicle projection area. As a result, this approach can increase well-distributed bone cement diffusion while preventing cement leakage into the spinal canal.

Clinical and patient-reported outcome after patient-specific 3D printer-assisted cranioplasty.

Various cranioplasty techniques exist for the reconstruction of cranial bone defects. Patient-specific implants can be produced in-house using a recently developed 3D printer-assisted cranioplasty technique. However, the resulting cosmetic outcomes from the patient's perspective are underreported. With our case series, we aim to present the clinical outcome, morbidity rate, patient-reported cosmetic results, and cost-effectiveness of patient-specific3D printer-assisted cranioplasty technique. This is a consecutive retrospective case series of adult patients undergoing cranioplasty using the patient-specific 3D printer-assisted technique. As primary endpoint, the functional outcome based on modified Rankin scale (mRS) at discharge and follow-up was assessed. A prospective telephone survey was conducted to collect and provide patient-reported outcomes. Thirty-one patients underwent patient-specific 3D printer-assisted cranioplasty, mostly to reconstruct frontotemporoparietal (61.3%) and frontotemporal defects with orbital involvement (19.4%). Good functional outcome (mRS ≤ 2) at discharge and during the last follow-up was achieved in 54.8% (n = 17) and 58.1% (n = 18) patients. Overall, the rate of clinically relevant surgery-related complications was 35.5% (n = 11). Postoperative epidural hematoma/collection (16.1%) and infections (12.9%) were the most frequent complications. Permanent morbidity occurred in one patient (3.2%) with postoperative acute ipsilateral vision loss after frontotemporal cranioplasty with orbital involvement. No surgery-related mortality occurred. The mean patient-reported cosmetic satisfaction score was 7.8 ± 1.5, with 80% of patients reporting satisfying or very satisfying cosmetic results. No significant differences were seen between the different defect localization regarding the cosmetic outcome. The mean manufacturing costs of a patient-specific 3D printer-assisted implant ranged from 748 to 1129 USD. Based on our case series, patient-specific 3D printer-assisted cranioplasty is cost-effective and leads to satisfying cosmetic results, especially in large defects and/or defects with complex geometry.