Success Rate After 2-Stage Spacer-Free Total Hip Arthroplasty Exchange and Risk Factors for Reinfection: A Prospective Cohort Study of 187 Patients.

BACKGROUND: Two-stage prosthesis exchange is the treatment of choice for chronic periprosthetic joint infection (PJI) of a total hip arthroplasty (THA), especially when the bone and surrounding soft tissues are compromised or difficult-to-treat pathogens are implicated. The aims of our study were as follows: (1) to determine the outcome of 2-stage prosthesis exchange for the treatment of PJI after THA and (2) to determine the risk factors for reinfection leading to subsequent revision surgeries after reimplantation. METHODS: We prospectively enrolled 187 consecutive patients who underwent a 2-stage THA exchange with resection arthroplasty for PJI from 2013 to 2019. The mean (± SD) duration of follow-up was 54.2 ± 24.9 months (range, 36 to 96), and the mean interval until reimplantation was 9.8 ± 8.9 weeks (range, 2 to 38). All patients remained in a spacer-free girdlestone situation between the 2 stages of treatment. Patients who remained infection-free after their 2-stage treatment were considered to have achieved treatment success. RESULTS: The overall success rate was 85.6%. The cumulative probability of reinfection was 11.5% after one year and 14% after 2 years after reimplantation. High virulence or difficult-to-treat pathogens were significant and independent risk factors for reinfection (HR [hazard ratio] = 3.71, 95% CI [confidence interval]: 1.47 to 9.36, P = .006 and HR = 3.85, 95% CI: 1.73 to 8.57, respectively, P = .001), as was previous 2-stage hip prosthesis exchange (HR = 3.58, 95% CI: 1.33 to 9.62, P = .01). Overall reoperation and revision rates were 26.2 and 16.6%, respectively. Re-infected patients had an 80% higher probability of reoperation than noninfected ones (P < .001, log-rank = 102.6), and they were 55% more likely to undergo revision surgery during their follow-up (P < .001, log-rank = 55.4). CONCLUSIONS: Reinfection rates after 2-stage spacer-free THA revision for PJI still remain high but are comparable to those including cement spacers. Patients who have had prior failed 2-stage implant exchanges or are infected by high-grade or difficult-to-treat pathogens are at high risk for treatment failure.

3D-printed glenoid implant reconstruction, after partial scapulectomy for malignant tumors: a case series.

PURPOSE: Glenoid tumors are extremely rare, and reconstruction remains very challenging. The aim of this study is to present the clinical and functional outcomes, of a new glenoid reconstruction method using 3-dimensional-printed implant. METHODS: Four patients with primary glenoid tumors underwent reconstruction using 3-dimensional-printed glenoid implant linked with reverse shoulder arthroplasty. We retrospectively reviewed the clinical and functional outcome, using MSTS and DASH score, as well as complications' rate. RESULTS: Wide excision was achieved in all patients. No local recurrence or distant metastasis was diagnosed at the follow-up period. The mean MSTS score was 80.5%, and DASH score was 15.2%. According to Hendersons' classification, there were no postoperative complications. CONCLUSION: The use of 3-dimensional-printed implants, can be a very reliable solution with satisfying clinical and functional outcomes for reconstruction, in patients with musculoskeletal malignancies of the glenoid. Level of evidence IV Treatment Study.

Hallmarks in the History and Development of Total Hip Arthroplasty.

Total hip replacement remains one of the most successful and popular operative techniques in orthopedic surgery. Over several decades, several patients have been benefited by this mechanical and surgical achievement. It is an innovation that stands among the most significant surgical and technological achievements of the 20th century. The purpose of this review was to summarize the main landmarks on the evolution of hip surgery and the resulting modern total hip arthroplasty technique.

The Safety and Efficacy of Microporous Polysaccharide Hemospheres in Terms of the Complication Rates in Total Hip Arthroplasty for Femoral Neck Fractures: A Control-Matched Retrospective Cohort.

AIMS: This study aimed to assess the safety and efficacy of microporous polysaccharide hemospheres (MPSHs) in managing blood loss and reducing the risk of postoperative haematoma and early periprosthetic joint infection (PJI) following total hip arthroplasty (THA) for femoral neck fracture (FNF), in the context of the existing treatment challenges. METHODS: A control-matched retrospective analysis of 163 patients undergoing unilateral primary THA for displaced FNF between 2020 and 2023 was performed. The study group consisted of 74 patients who received MPSH administered intraoperatively. The control group consisted of 89 patients who received no topical haemostatics. One-to-one case-control matching between groups was performed. The primary outcome was a perioperative change in the haematologic values (haemoglobin, red blood cell count, haematocrit, platelet concentration) and transfusion rate. The secondary outcomes were the incidence of postoperative local haematoma formation, prolonged wound secretion, surgical site infection (SSI), and PJI within 3 months of surgery. RESULTS: Our analysis found no statistically significant differences in the haematologic parameters between the control and study cohorts. The changes in the haemoglobin concentration were not significant between the control group (3.18 ± 1.0 g/dL) and the treatment group (2.87 ± 1.15 g/dL) (p = 0.3). There were no significant differences (p = 0.24) in the haematocrit and red blood cell concentration (p = 0.15). The platelet levels did not significantly differ (p = 0.12) between the groups. Additionally, we found no significant discrepancy in the incidence of early PJI or blood transfusion rates between the groups. No adverse effects following MPSH use were recorded in the study group. CONCLUSIONS: Routine use of MPSH in THA for FNF management appears to be safe, with no observed adverse events related to Arista® use. Although there was a tendency towards reduced blood loss in the Arista® AH group, MPSH did not significantly impact bleeding complications, local haematoma formation, or subsequent PJI.

Limb Salvage and Pelvic Reconstruction With Endoprosthesis After Pelvic Tumor Resection: A Narrative Review.

Periacetabular defects following tumor resection present formidable challenges in reconstruction and continue to pose clinical difficulties. Historically, treatment approaches leaned towards hindquarter amputation; however, due to associated morbidities and functional limitations, limb-sparing procedures gained prominence in the 1980s. Nevertheless, the intricacies of pelvic anatomy and the imperative of achieving wide surgical margins while preserving essential structures make pelvic tumor resection and subsequent reconstruction inherently complex. Various reconstruction modalities have been explored, including non-vascularized fibular grafts and prosthetic implants. Among these options, the LUMiC® endoprosthesis stands out as a promising solution for pelvic reconstruction post-tumor resection. Characterized by a modular design featuring a hydroxyapatite-coated stem and acetabular cup, this device has shown favorable implant survival rates in studies, despite encountering complications primarily associated with soft tissue failure, dislocation, and infection. Notably, the incidence of complications varies across studies. The Henderson classification system delineates these complications, encompassing soft tissue issues, aseptic loosening, periprosthetic fractures, infections, and tumor recurrence. Despite the encouraging functional outcomes associated with the LUMiC® endoprosthesis, it is not immune to limitations. Concerns persist regarding complications such as dislocation and infection, underscoring the imperative for further research to evaluate the long-term durability and reliability of this reconstructive approach. Moreover, advancements in surgical techniques, perioperative management, and the advent of navigation-assisted procedures hold promise for enhancing outcomes and mitigating complication rates in pelvic reconstruction surgeries.

Risk factors for peri-megaprosthetic joint infections in tumor surgery: A systematic review.

BACKGROUND: Peri-megaprosthetic joint infections (PJI) in tumor surgery are complex and challenging complications that significantly impact the outcomes of the patients. The occurrence of PJI poses a substantial threat to the success of these operations. This review aims to identify and summarize the risk factors associated with PJI in tumor surgery with megaprosthetic reconstruction as well as to determine the overall risk of PJI in limb salvage surgery. METHODS: A thorough examination of published literature, scrutinizing the incidence of PJI in tumor prostheses after limb salvage surgery was done. Research studies that documented the incidence of PJI in tumor patients who underwent limb salvage surgery, and explored the risk factors associated with the occurrence of PJI were deemed eligible. RESULTS: A total of 15 studies were included in the analysis and underwent comprehensive examination. After the exploration of key parameters, several significant risk factors for PJI concerning the type of implant coating, surgical site characteristics, patient demographics, and procedural factors were recorded. DISCUSSION: The findings underscore the need for a nuanced approach in managing tumor patients undergoing limb salvage surgery and megaprosthetic reconstruction, with emphasis on individualized risk assessments and individualized preventive strategies.

Clinical Outcome after Surgical Treatment of Sacral Chordomas: A Single-Center Retrospective Cohort of 27 Patients.

Introduction: The aims of our study were (1) to determine disease-specific and disease-free survival after the en-bloc resection of sacral chordomas and (2) to investigate potential risk factors for tumor recurrence and major postoperative wound-related complications. Methods: We retrospectively analyzed 27 consecutive patients with sacral chordomas who were surgically treated in our institution between 2004 and 2022. Three patients (11.1%) had a recurrent tumor and four patients (14.8%) had history of a second primary solid tumor prior to or after their sacral chordoma. A combined anterior and posterior approach, colostomy, plastic reconstruction, and spinopelvic instrumentation were necessitated in 51.9%, 29.6%, 37%, and 7.4% of cases, respectively. The mean duration of follow-up was 58 ± 41 months (range= 12-170). Death-related-to-disease, disease recurrence, and major surgical site complications were analyzed using Kaplan-Meier survival analysis, and investigation of the respective risk factors was performed with Cox hazard regression. Results: The estimated 5-year and 10-year disease-specific survival was 75.3% (95% CI = 49.1-87.5%) and 52.7% (95% CI = 31-73.8%), respectively. The estimated 1-year, 5-year, and 10-year disease-free survival regarding local and distant disease recurrence was 80.4% (95% CI = 60.9-91.1%), 53.9% (95% CI = 24.6-66.3%), and 38.5% (95% CI = 16.3-56.2%), respectively. The mean survival of the recurred patients was 61.7 ± 33.4 months after their tumor resection surgery. Conclusions: Despite the high relapse rates and perioperative morbidity, long-term patient survival is not severely impaired. Positive or less than 2 mm negative resection margins have a significant association with disease progression.

Rotational Thromboelastometry as a Diagnostic Tool for Persistent Infection in Two-Stage Exchange Arthroplasty.

Background/Objectives: There is a lack of reliable biomarkers for diagnosis of infection eradication prior to second-stage reimplantation in two-stage exchange arthroplasty for periprosthetic joint infections (PJIs). The aim of this study was to assess the diagnostic accuracy of rotational thromboelastometry (ROTEM) for persistent infection in two-stage exchange arthroplasties. Methods: A pilot, retrospective analysis was performed including 70 patients who underwent a two-stage exchange arthroplasty for PJI. They were categorized as patients without (n = 64) or patients with persistent infection (n = 6) prior to reimplantation. Definition of persistent infection prior to reimplantation was based on the 2018 ICM criteria. Conventional coagulation biomarkers and ROTEM parameters were compared between groups. Results: Higher FIBTEM MCF values were associated with persistent infection (odds ratio [OR], 1.30, 95% confidence interval [CI], 1.04-1.63; p = 0.020), and FIBTEM MCF had the highest diagnostic accuracy for persistent infection prior to second-stage reimplantation (AUC, 0.907; 95% CI, 0.812-1.000). A cut-off value ≥ 18 mm for FIBTEM MCF was found to have 100.0% sensitivity and 73.4% specificity for diagnosing persistent infection prior to second-stage reimplantation. Moreover, the diagnostic accuracy of FIBTEM MCF was higher than that of fibrinogen levels (p = 0.036) and D-dimer (p = 0.006). Conclusions: Our findings indicate that ROTEM parameters have the potential to identify persistent infections before reimplantation in two-stage exchange arthroplasties for PJI. Such coagulation biomarkers could provide guidance regarding the optimal timing for reimplantation. Further studies in larger populations are warranted to validate the diagnostic accuracy of ROTEM parameters for persistent PJI.

Diagnostic Accuracy of Rotational Thromboelastometry for Low-Virulence Periprosthetic Joint Infections: A Pilot Study.

BACKGROUND: Periprosthetic joint infections (PJIs) are associated with altered coagulation dynamics; therefore, coagulation laboratory studies could be valuable for diagnosing PJI. This study aimed to evaluate the diagnostic role of Rotational Thromboelastometry (ROTEM) in detecting PJIs caused by low-virulence pathogens. METHODS: A retrospective study was conducted, enrolling 78 patients who underwent exchange arthroplasty due to PJI due to high-virulence pathogens (Group A, n = 16), low-virulence pathogens (Group B, n = 20), or due to aseptic loosening (Group C, n = 20). Preoperative laboratory findings were compared among the three groups. RESULTS: Several ROTEM parameters differed in patients with PJIs caused by low-virulence pathogens, indicating a link between these infections and hypercoagulability. The development of low-virulence PJIs was associated with a higher maximum clot firmness (MCF) (Odds Ratio, 1.12; 95% Confidence Interval, 1.04-1.21; p = 0.001). Additionally, EXTEM MCF was found to have the highest diagnostic accuracy for these infections (Area Under the Curve, 0.841; sensitivity 90.0%; specificity 90.4%), surpassing that of C-reactive protein and the Erythrocyte Sedimentation Rate (p = 0.006 and p = 0.019, respectively). CONCLUSIONS: Our findings suggest that ROTEM analysis is a promising method for detecting the altered hemostatic dynamics associated with PJI caused by low-virulence pathogens.

Knee Arthrodesis with a Modular Silver-Coated Endoprosthesis for Infected Total Knee Arthroplasty with Extensive Bone Loss: A Retrospective Case-Series Study.

INTRODUCTION: Knee arthrodesis is a limb salvage intervention for persistent periprosthetic joint infection (PJI) when revision total knee arthroplasty fails. Conventional arthrodesis techniques are associated with the increased rate of complications, especially in patients with extensive bone loss and extensor tendon deficiency. METHODS: Eight patients with a modular silver-coated arthrodesis implant after failed exchange arthroplasty for infection, were retrospectively reviewed. All patients had significant bone loss, while 5 displayed extensor tendon deficiency. Survivorship, complications, leg length discrepancy, median Visual Analogue Scale (VAS) and Oxford Knee score (OKS) were evaluated. RESULTS: The median follow up was 32 months (range 24-59 months). The survivorship rate of the prosthesis was 86% during the minimum time of follow up of 24 months. In one patient recurrence of the infection was observed and above-knee amputation was performed. The median postoperative leg length discrepancy was 2.07 ± 0.67 cm. Patients were able to ambulate with mild or no pain. The median VAS and OKS was 2.14 ± 0.9 and 34.7 ± 9.3, respectively. CONCLUSIONS: The results of our study demonstrated that knee arthrodesis with a silver coated arthrodesis implant, performed for persistent PJI in patients with significant bone loss and extensor tendon deficit, provided a stable construct, allowed eradication of infection and was associated with good functional outcome.

A Pilot Observational Study Evaluating the Diagnostic Capacity of Rotational Thromboelastometry in Periprosthetic Joint Infections.

BACKGROUND: Periprosthetic joint infections (PJIs) are associated with altered hemostatic dynamics; therefore, coagulation laboratory methods such as rotational thromboelastometry (ROTEM) may be valuable in their diagnosis. The aim of this study was to evaluate the diagnostic role of ROTEM in PJI. METHODS: A diagnostic study was conducted including 65 patients who underwent revision total hip arthroplasty or total knee arthroplasty due to PJI (30 patients) or aseptic loosening (35 patients). Preoperative laboratory evaluation included conventional coagulation studies, inflammatory markers, and ROTEM analysis. These parameters were compared between patients with PJI and patients with aseptic loosening. RESULTS: Several ROTEM parameters differed in the patients with PJI, indicating a higher coagulation potential associated with PJI. Specifically, the development of PJI was associated with higher EXTEM maximum clot firmness (MCF) (odds ratio [OR], 1.12 [95% confidence interval (CI), 1.04 to 1.20]; p = 0.001). Among the ROTEM parameters, EXTEM MCF was found to have the highest diagnostic accuracy for PJI (area under the receiver operating characteristic curve, 0.850; sensitivity, 76.6%; specificity, 91.4%), which was comparable with C-reactive protein (CRP) (p = 0.22) and erythrocyte sedimentation rate (ESR) (p = 0.65), but higher than D-dimer (p = 0.037). Moreover, the combined diagnostic accuracy of elevated EXTEM MCF and CRP was improved compared with CRP alone (p = 0.019). CONCLUSIONS: Our results indicate that ROTEM analysis might be helpful for the detection of the hemostatic derangements that are associated with the development of PJI. However, because of the small size of this pilot study, further research is needed to investigate the value of incorporating viscoelastic studies in diagnostic scores for PJI. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Oncological and Functional Outcomes after Hemicortical Resection and Biological Reconstruction Using Allograft for Parosteal Osteosarcoma of the Distal Femur.

Background: Parosteal osteosarcoma (PAOS) is a surface osteosarcoma. Treatment options include wide excision and endoprosthetic or allograft. However, due to the low local recurrence and metastasis rate, when it appears in the posterior surface of the distal femur, the lesion can be managed with hemicortical wide resection and biological reconstruction with hemicortical allograft. The purpose of this study is to evaluate the oncological and functional outcomes of patients with parosteal osteosarcoma (PAOS) of the posterior cortex of the distal femur who underwent biological reconstruction after hemicortical resection. Methods: Eleven patients who underwent wide tumor resection and defect reconstruction of the posterior surface of the distal femur using hemicortical allograft were retrospectively studied. Local recurrence, metastasis, complications, and the functional outcome using the Musculoskeletal Tumor Society (MSTS) scoring system were evaluated. Results: The average postoperative follow-up period was 53.64 months (range, 30 to 84 months). At the latest follow-up, all patients had no evidence of disease without metastases. One patient with local recurrence underwent revision surgery with fibula autograft reconstruction. The mean MSTS score was 93.45 ± 3.56. Conclusions: Treatment of patients with PAOS of the posterior aspect of the distal femur with hemicortical resection and allograft reconstruction has satisfactory oncological and functional outcome and low complication rates.

Prosthetic Reconstruction of the Shoulder After Resection of Proximal Humerus Bone Tumor.

Prosthetic reconstruction after wide resection of tumors of the proximal humerus presents a unique challenge. The shoulder is a complex articulation, and patients have high expectations for postoperative function. The goal of this study is to compare functional outcomes, oncologic outcomes, and complication rates for 2 reconstructive methods. Forty patients with proximal humeral tumors were reviewed retrospectively. Proximal humeral endoprosthesis (PHE) was used for 21 patients, and reverse shoulder arthroplasty (RSA) was used for 19 patients. Clinical results, oncologic outcomes, and complication rates were assessed. The functional outcomes of the patients were assessed with the Musculoskeletal Tumor Society scoring system (MSTS), the shortened version of the Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, and shoulder range of motion. The mean follow-up was 62±15 months. Shoulder dislocations occurred among 8 patients with PHE and 1 patient with RSA (P=.021). The other complication rates were similar for the 2 groups (P<.05). At the latest follow-up, the mean MSTS score was 68±10.3 for those with PHE and 76±7.7 for the patients with RSA (P=.72). However, the QuickDASH score was significantly better (P=.031) for those with RSA (mean, 19±6.3) compared with patients with PHE (mean, 30±4.8). Additionally, shoulder active abduction and forward flexion were significantly greater for the RSA group (P=.04 and P=.03, respectively). Five patients had local recurrence. Prosthetic reconstruction after oncologic re-section of the proximal humerus is associated with significant limitation of shoulder range of motion and a high rate of revision surgery. However, in this study, RSA was associated with fewer dislocations, improved Quick-DASH score, and greater abduction and forward flexion compared with PHE. [Orthopedics. 2022;45(6):e335-e341.].

The Hypercoagulable Profile of Patients with Bone Tumors: A Pilot Observational Study Using Rotational Thromboelastometry.

Introduction: A detailed evaluation of the malignancy-associated coagulopathy (MAC) in surgical patients with bone tumors may allow for more effective thromboprophylactic measures. The purpose of this study was to assess the perioperative hemostatic changes in patients with bone tumors, using rotational thromboelastometry (ROTEM). Methods: An observational study was performed, including 50 patients with bone tumors who underwent oncologic resection and 30 healthy controls, matched for age and gender. The preoperative and postoperative laboratory evaluation of coagulation in both groups included conventional coagulation tests and a ROTEM analysis. The results of the conventional coagulation tests and the ROTEM analysis were compared between the two groups. Results: The results of the conventional coagulation tests were comparable between the tumor patients and the healthy controls. However, compared to the healthy adults, the tumor patients had lower CT (p < 0.001) and CFT (p < 0.001) values suggesting a rapid induction of the coagulation cascade, elevated A10 (p < 0.001) and MCF (p < 0.001) values indicating a higher clot strength and platelet activation, and elevated LI60 (p < 0.001) values indicating hypofibrinolysis in patients with bone tumors. The multiple linear regression analysis (controlling for potential confounding factors) confirmed the independent association of bone tumors with these hemostatic changes. Conclusions: Our results support the advantageous use of a ROTEM in patients with bone tumors over conventional coagulation tests because the qualitative changes in the hemostatic profile of these patients that can be detected by a ROTEM analysis cannot be identified by conventional tests. The ROTEM results indicate that the hypercoagulable state in patients with bone tumors is caused by the malignancy-associated activation of the coagulation cascade, platelet activation, and hypofibrinolysis.

The Safety and Efficacy of Tranexamic Acid in Oncology Patients Undergoing Endoprosthetic Reconstruction and a ROTEM-Based Evaluation of Their Hemostatic Profile: A Pilot Study.

BACKGROUND: An endoprosthetic reconstruction in musculoskeletal oncology patients is associated with significant blood loss. The purpose of this study is to evaluate the safety and efficacy of tranexamic acid (TXA) for these patients and to assess any changes in their hemostatic profile using rotational thromboelastometry (ROTEM). METHODS: A retrospective observational study was performed including 61 patients with primary or metastatic bone tumors who underwent surgery. Group A (n = 30) received both intravenous and local TXA whereas Group B (n = 31) was the control group. The primary outcomes were perioperative blood loss and blood unit transfusions and the secondary outcomes included the incidence of thromboembolic complications and a change in blood coagulability as reflected by ROTEM parameters. RESULTS: The median difference in blood loss between the two groups was 548.5 mL, indicating a 29.2% reduction in the 72 h blood loss following TXA administration (p < 0.001). TXA also led to a reduced transfusion of 1 red blood cell (RBC) unit per patient (p < 0.001). The two groups had similar rates of thromboembolic complications (p = 0.99). The antifibrinolytic properties of TXA were confirmed by the significantly higher INTEM, FIBTEM and EXTEM LI60 (p < 0.001, p = 0.005 and p < 0.001, respectively) values in the TXA group. CONCLUSION: Tranexamic acid was associated with a significant reduction in perioperative blood loss and transfusion requirements without a complete shutdown of the fibrinolysis. Larger studies are warranted to assess the frequency of these outcomes in musculoskeletal oncology patients.

The Procoagulant Effect of COVID-19 on the Thrombotic Risk of Patients with Hip Fractures Due to Enhanced Clot Strength and Fibrinolysis Shutdown.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) in patients with hip fractures is associated with increased incidence of venous thromboembolism (VTE). The purpose of this study was to evaluate the hemostatic alterations of COVID-19 that are associated with a higher thrombotic risk using rotational thromboelastometry (ROTEM). METHODS: A retrospective observational study was performed including 20 COVID-19 patients with hip fractures. To compare the coagulopathy of patients with mild COVID-19 and hip fractures with the coagulopathy associated with each of these two conditions separately, we used two previously recruited groups of patients; 198 hip fracture patients without COVID-19 and 21 COVID-19 patients without hip fractures. The demographics, clinical parameters, conventional coagulation parameters and ROTEM findings of the three groups were analyzed and compared. RESULTS: COVID-19 hip fracture patients had higher amplitude of clot firmness at 10 min (p < 0.001), higher alpha angle (p < 0.001), higher lysis index at 60 min (p < 0.001), and shorter clot formation time (p < 0.001) than non-COVID-19 hip fracture patients, indicating increased clot strength and impaired fibrinolysis due to COVID-19. The value of lysis index at 60 min (99%) in COVID-19 patients with hip fractures was consistent with fibrinolysis shut down. Multivariable linear regression analysis further confirmed that COVID-19 resulted in increased amplitude of clot firmness at 10 min (p < 0.001), increased maximum clot firmness (p < 0.001), increased lysis index at 60 min (p < 0.001) and increased alpha angle (p < 0.001), but significantly shortened clot formation time (p < 0.001). DISCUSSION: The higher thrombotic risk in COVID-19 patients with hip fractures is characterized by increased clot strength and fibrinolysis shutdown, as shown by ROTEM findings. Further prospective studies are warranted to evaluate the need for modification of thromboprophylaxis to balance the hemostatic derangements of COVID-19 patients with hip fractures.

Three-Dimensional Printed Calcaneus Implant for Open Calcaneal Fracture with Extensive Bone Loss: A Case Report and Literature Review.

Open calcaneal fractures with extensive bone loss and severe soft tissues injuries are very rare. There is no treatment protocol for these severe injuries. The incidence of infection, osteomyelitis, and amputation is high compared to closed calcaneal fractures. An independent prognostic factor for increased complications is the high type of fracture according to Gustillo and Anderson's classification. A one-stage or two-stage procedure with open reduction and internal fixation, external fixation, percutaneous pinning, minimally invasive procedures, and subtalar arthrodesis are treatment options. We present a case of open type IIIB fracture of the calcaneus with extensive bone loss managed with a two-stage procedure. First, a cement spacer was inserted to fill the void and then, after the soft tissue envelope had healed with no sign of infection, a three-dimensional (3D) printed custom-made calcaneus implant was inserted. This is the first report in the literature of using a 3D custom-made calcaneal implant for a severe open calcaneal fracture with extensive osseous defect. At one-year follow-up, plain radiographs of the foot showed the calcaneus implant in place. The American Orthopedic Foot and Ankle score (AOFAS) was 76, and the patient had mild restrictions to his daily activities due to mild heel pain.

Efficacy of antimicrobial coated orthopaedic implants on the prevention of periprosthetic infections: a systematic review and meta-analysis.

Introduction: Implant-associated infections are a major problem in orthopaedic surgery. Local delivery systems of antimicrobial agents on the implant surface have attracted great interest recently. The purpose of this study was to identify antimicrobial coatings currently used in clinical practice, examining their safety and effectiveness in reducing post-operative infection rates. Materials and Methods: A systematic review was conducted in four databases (Medline, Embase, Cochrane, Cinahl) according to the Preferred Reporting Items for Systematic reviews and Meta-analysis (PRISMA) guidelines up to December 2019, using the key words "orthopaedic implant coated", "coated implant infection", "silver coating " and "antibiotic coating". Results: Seven articles involving 1307 patients (561 with coated implants and 746 controls who were not) comparing the incidence of periprosthetic infections after the application of internal fracture fixation, total arthroplasties and endoprostheses were evaluated. Three different coating technologies were identified: gentamicin coating for tibia nail and total arthroplasties; silver technology and povidone-iodine coating for tumour endoprostheses and titanium implants. Meta-analysis demonstrated that patients who were treated with antimicrobial coated implants presented lower infection rates compared to controls over the seven studies (Q = 6.1232, I2 = 0.00, 95% CI: 1.717 to 4.986, OR: 2.926, Z= 3.949, p<0.001). Subgroup statistical analysis revealed that each coating technique was effective in the prevention of periprosthetic infections (Q = 9.2606, I2 = 78.40%, 95% CI: 1.401 to 4.070, OR: 2.388, Z= 3.200, p<0.001). Conclusion: All technologies were reported to have good biocompatibility and were effective in the reduction of post-operative peri-prosthetic infection rates.

Staphylococcus Aureus Osteomyelitis as an Inducer of Tolerance to Escherichia Coli Pyelonephritis: an Experimental Study.

The high incidence of osteomyelitis in vulnerable populations like those with multiple injuries or elderly undergoing joint arthroplasties generates the question what may be their responses to subsequent infection by high virulent isolates. Rabbits were subject to two operations at three week intervals; sham osteomyelitis and sham pyelonephritis (group S); sham osteomyelitis and Escherichia coli pyelonephritis (group P); and Staphylococcus aureus osteomyelitis and E. coli pyelonephritis (group OP). Survival was recorded; cytokine stimulation of circulating mononuclear cells (PBMCs) and tissue myeloperoxidase (MPO) activity and bacterial growth were monitored. In some experiments, dalbavancin treatment was given before pyelonephritis. Healthy PBMCs were pre-treated with bone homogenate, S. aureus or both. Mortality of groups S, P and OP after induction of pyelonephritis was 0%, 50% and 8.3% respectively. Tumour necrosis factor-alpha (TNFα) production by PBMCs was significantly lower in the OP group at 48 hours. E. coli bacterial load was similar in groups P and OP at death or sacrifice whereas the MPO activity of group OP was decreased. Production of TNFα was further decreased among dalbavancin treated rabbits; in these rabbits tissue MPO was increased. TNFα production decreased when healthy PBMCs pre-treated with bone homogenate, S. aureus (HKSA) or both were stimulated with E. coli (HKEC); production was further decreased in the presence of anti-TLR4 and anti-TLR9. It is concluded that staphylococcal osteomyelitis modulated the innate immune responses of the host leading to protection from death by highly virulent E. coli. Tolerance to TLR ligands is the most likely mechanism of action.

Glucocorticoid signaling and osteoarthritis.

Glucocorticoids are steroid hormones synthesized and released by the adrenal cortex. Their main function is to maintain cell homeostasis through a variety of signaling pathways, responding to changes in an organism's environment or developmental status. Mimicking the actions of natural glucocorticoids, synthetic glucocorticoids have been recruited to treat many diseases that implicate glucocorticoid receptor signaling such as osteoarthritis. In osteoarthritis, synthetic glucocorticoids aim to alleviate inflammation and pain. The variation of patients' response and the possibility of complications associated with their long-term use have led to a need for a better understanding of glucocorticoid receptor signaling in osteoarthritis. In this review, we performed a literature search in the molecular pathways that link the osteoarthritic joint to the glucocorticoid receptor signaling. We hope that this information will advance research in the field and propose new molecular targets for the development of more optimized therapies for osteoarthritis.