Hip Replacement Procedures Research Articles

The completeness of national hip and knee replacement registers.

National joint replacement registries were developed for prospective monitoring of outcomes and post-market surveillance of implants. Increasingly registry data informs practice. However, analysis of a registry can only be as good as the data it captures on the population of interest. We aimed to analyze completeness of reporting of hip and knee replacement procedures for all national registries worldwide. We analyzed annual reports and data provided following written requests to all active national hip and knee replacement registries. Coverage was defined as the proportion of hospitals in the country that participate in the registry. Procedure completeness was defined as the proportion of procedures successfully captured by the registry. 14 national registries were included, spanning years 2004 to 2022. Coverage was complete in 10. Median procedure completeness for primary hip and knee replacement across all years was 96.5% (interquartile range [IQR] 94.0-97.7%). Median procedure completeness for revisions was 88.5% (IQR 81.0-92.5%). The terminology used and method of calculation of completeness estimates in the registries were variable. National hip and knee replacement registry data generally reflects excellent coverage (full in 10 of 14 registries) and completeness (primary procedures 96.5% and revisions 88.5%) over the last 2 decades.

Dr. John H. Charnley: An Architect and Pioneer of the Modern Era of Hip Replacement Surgery.

Dr. John H. Charnley (1924-1982) revolutionized orthopedic surgery with his groundbreaking innovations in hip replacement with exceptional skill and a holistic thought process, which has had an impact to this day in the world of arthroplasty. His innovations have improved the lives of numerous patients who had painful and discomforting arthritis and have been instrumental in providing painless mobile joints to these patients. This article reviews Charnley's contributions to the development of low-friction arthroplasty using ultra-high-molecular-weight polyethylene and the use of acrylic bone cement for improved implant fixation. These advancements dealt with the critical issues of friction, wear, and implant stability, significantly enhancing patient outcomes and implant longevity. Charnley's work led to the global standardization of hip replacement procedures, influencing orthopedic practices globally and setting benchmarks for modern implant designs. His principles continue to inform ongoing research and advancements in hip replacement technology. This review also discusses the challenges and criticisms faced by Charnley's innovations, reflecting on their evolution and impact on contemporary orthopedic surgery. A surgeon blessed with a noble heart who would help his patients who were in trouble by going out of the way and was determined for a better tomorrow, self-driven by his compassion and ambition for treating his patients. Charnley's legacy remains pivotal in shaping the field and improving the quality of life for patients undergoing hip replacement surgery.

How Does the New Australian EQ-5D-5L Value Set Impact Utility Scores? Analysis of Data from the Australian Orthopaedic Association National Joint Replacement Registry.

With advances in health state valuation methods, new value sets may be developed for some countries. Quantifying the impact of moving between existing and new value sets is critical for guiding decisions around utility score interpretation, reporting and comparison with published scores. The aim of this study is to examine, using large-scale national registry data, how the new Australian EQ-5D-5L value set impacts utility scores for patients undergoing joint replacement. Data from the Australian Orthopaedic Association National Joint Replacement Registry were used for this analysis. All primary total hip (THR), knee (TKR), and shoulder replacement (TSR) procedures between 2018 and 2022 with pre-operative and 6-month post-operative EQ-5D-5L data were included. Utility scores were generated using the 2013 and 2023 Australian value sets ('previous' and 'new' value sets, respectively) and analysed descriptively for each joint replacement cohort. Agreement between the two utility score sets was evaluated using concordance correlation coefficients and Bland-Altman plots. EQ-5D-5L data were available for 17,576 THR, 23,010 TKR, and 1667 TSR procedures. The new value set produced a lowest possible EQ-5D-5L utility score of -0.30 (compared with -0.68 previously) and fewer patients had 'worse-than-dead' quality of life (score < 0.00) before surgery. Mean pre-operative scores were 0.21 (THR), 0.19 (TKR), and 0.17 (TSR) units higher with the new value set, and mean post-operative scores were 0.11-0.14 units higher. The new value set resulted in smaller effect sizes for the THR (1.08 versus 1.23) and TKR cohorts (0.86 versus 0.92). There was moderate-to-good overall agreement (coefficients: 0.70-0.80), but concordance varied by time point. Although acceptable agreement was evident, the new Australian value set produces less extreme negative utility scores and markedly higher group-level scores. Transition to reporting new EQ-5D-5L utility scores will require accompanying explanation to signal measurement modifications rather than better quality of life.

THE EVALUATION OF TOTAL HIP ARTHROPLASTY IN THE MANAGEMENT OF SPASTIC PAINFUL HIP DISLOCATION IN CEREBRAL PALSY

Spasticity used to be considered a contraindication for total hip replacement (THR) procedures. Due to the development of implants as well as surgical skills, THR became an option for the treatment of painful dislocation of the hip joint in patients with spastic plegia. The aim of this study was an evaluation of mid-term results of THR in spastic CP adolescent patients with painful hips with hip joint subluxation or dislocation.In 2014–2022, 18 pts (19 hips) with CP aged 16 to 20 years underwent THR in our department. The mean follow-up was 4 years (range: 1 – 9 years). Results were evaluated using the Gross Motor Function Scale, VAS scale in accordance with the Ashworth scale, types of implants used (dual mobility cup and not dual mobility cup), and radiological assessment (Crowe scale). Complications have been thoroughly analyzed.In 10 pts there has been an improvement in the GMFSC scale average from 1 to 2 points observed after the surgery. All pts have improved in the VAS scale average of 8 points (from 10 to 7). According to the Crowe scale repositioning of preoperative dislocation to primary acetabulum was achieved in all cases. Complications occurred in 4 cases: dislocations of 2 THR with dual mobility cup and 2 THR with non-dual mobility cup requiring revision surgery with good final result. No statistical significance was noted according to the type of cup (Mann-Whitney U Test).The most important risk factor for complications is severe spasticity. We believe, that CP pts with painful hips should be treated using THR. We didn't observe any significant differences between the types of implants.These findings may serve as a basis for the prediction of outcomes of THR treatment in this specific group of pts.Level of evidence: Case-control or retrospective comparative study-Level III

The Relationship Between Patient-Reported Outcome Measures (PROMs) in Patients Undergoing Hip and Knee Joint Replacement Surgery and Social Deprivation on the Wirral.

This study aimed to investigate the associa-tion between patient-reported outcome measures (PROMs), both pre- and post-operatively, and socio-economic deprivation among patients undergoing hip and knee replacement surgeries in the diverse socioeconomic region of Wirral. A retrospective cohort study was conducted, involving 1666 adult patients who underwent hip or knee replacement procedures between 2012 and 2019. Socioeconomic deprivation was assessed using the Index of Multiple Deprivation (IMD). Pre- and post-operative outcomes were measured using the Oxford Hip and Knee scores. The mean scores for both pre-and post-operative assessments (Q1 and Q2) exhibited a strong positive correlation with PROM scores, regardless of gender, across both hip and knee replacements. However, the mean difference in scores between Q1 and Q2 showed no significant correlation with the IMD decile. Notably, patients residing in areas of higher socioeconomic deprivation demonstrated lower PROMs both before and after the surgery. The Oxford Hip and Knee scores are widely employed for evaluating health status in patients. In our study, these scores were influenced by IMD decile, supporting the holistic assessment approach employed by the treating unit, which does not rely solely on PROM scores as a trigger for arthroplasty discussions. Furthermore, our findings align with the practice of NHS Digital, which publishes PROM scores based on changes in PROM scores pre- and post-operation rather than absolute PROM scores. This approach appears to be less influenced by deprivation in the catchment area, as the improvement or change in scores was poorly correlated with socioeconomic factors.

Trends in Incidence of Hip Fracture and Hip Replacement in Denmark, 1996 to 2018

The past several decades have witnessed substantial changes in treatments that are particularly relevant for older patients. To assess changes in national-level incidence rates of fracture- and musculoskeletal-related (ie, arthritis-related) hip replacement procedures for individuals aged 40 to 104 years over a 23-year period in Denmark. This cohort study used national Danish health registers to include the Danish population aged 40 to 104 years from January 1, 1996, to December 31, 2018. Data were analyzed from May 31, 2022, to February 14, 2024. Age- and period-specific incidence rates of hip fracture and hip replacement stratified on fracture-related vs arthritis-related indication. From 1996 to 2018, a total of 3 664 979 individuals were followed up for a mean (SD) of 14.6 (7.7) years, resulting in a follow-up time of 53 517 861 person-years and 158 982 (first) hip fractures, of which 42 825 involved fracture-related hip replacement procedures. A further 104 422 individuals underwent arthritis-related hip replacement. During the first 2 decades of the 21st century, hip fracture rates declined by 35% to 40% for individuals aged 70 to 104 years, and the proportion of the population undergoing fracture-related hip replacement increased by 50% to 70%, with modest variation across those aged 75 to 99 years. Rates of arthritis-related hip replacements peaked for individuals aged 75 to 79 years, but with the largest relative rate increase (75%-100%) occurring for those aged 80 to 94 years, primarily from 2001 to 2015, whereafter it remained nearly unchanged. The decline in rates of arthritis-related hip replacement after 75 to 79 years of age was gradual and did not suggest an upper age limit for access to arthritis-related hip replacement. The findings of this cohort study suggest that during the past several decades in Denmark, the incidence of hip fractures declined by 35% to 40% among patients aged 80 to 104 years, while the proportion receiving fracture-related hip replacement remained relatively constant after 75 years of age. During the first decades of the 21st century, arthritis-related hip replacement incidence increased by 50% to 100% among older patients and stabilized hereafter, with no apparent cutoff age for this type of procedure. These patterns indicate a positive overall trend with declining hip fracture incidence over the last decades in Denmark, and the observed hip replacement incidence suggests that age is currently not a major determining factor guiding this type of surgery.

A cross-national performance comparison universal healthcare systems of Chile, Costa Rica, Italy, and Spain using OECD data

Abstract Objectives To analyze Organization for Economic Cooperation and Development (OECD) indicators for the Health Systems of Costa Rica, Spain, and Italy, focusing on year-to-year changes. Study design and methods Examining each country’s healthcare systems utilizes a value-for-money approach, aiming to outline their healthcare expenditures relative to the OECD average, while also assessing the value obtained from these investments. This involves contrasting reported indicator values for each country and the OECD average during a year close to the last decade’s outset (year 1) with data around 2020 (year 2). Results Results obtained are based on different indicators and the countries being examined. Costa Rica stood out with lowest healthcare investment, while Chile had the less population coverage for a set core of services. Italy and Spain achieved 100% healthcare coverage. All four regions reported decreased tobacco consumption in terms of non-medical determinants of health. Costa Rica showcased the highest vaccination coverage and experienced the most significant increase in this aspect within healthcare utilization. In the context of resource accessibility, waiting times from specialist assessment to treatment increased the most for hip replacement procedures in Chile, Costa Rica, Italy, and Spain. The Pharmaceutical Consumption analysis highlighted agents acting on the Renin-Angiotensin system as the most widely consumed category. Conclusion This analysis helps reveal the workings of diverse health systems, allowing us to pinpoint areas for potential improvement within each region. By examining the achievements and obstacles faced by other nations, policymakers and healthcare stakeholders acquire a valuable foundation on which to enact reforms.

Disparities in Access to Outpatient Surgery Related to Removal of Procedures from Medicare's Inpatient Only List.

We assessed the shift from inpatient to outpatient surgical care related to changes to the Inpatient Only List in 2020 and 2021 compared to 2019. The extent to which procedures shift from the inpatient to outpatient setting following removal from Medicare's Inpatient Only List is unknown. Many health systems also encouraged a shift from inpatient to outpatient surgery during the COVID-19 pandemic. Assessing the relative change in outpatient surgical utilization for procedures removed from the Inpatient Only List during COVID-19 would provide empirical data on whether reimbursement policy changes or inpatient capacity needs during the pandemic were more likely to shift care from the inpatient to outpatient setting. We used administrative data from the PINC AI Healthcare Database across 723 hospitals to determine the within-facility relative change in outpatient vs inpatient procedural volume in 2020 and 2021 compared to 2019 using a multivariable conditional fixed-effects Poisson regression model. We also assessed whether outpatient surgical utilization varied by race and ethnicity. Using a multivariable linear probability model, we assessed the absolute change in risk-adjusted 30-day complication, readmission, and mortality rates for inpatient and outpatient surgical procedures. In 2020 and 2021 compared to 2019 respectively, there was a 5.3% (95% CI, 1.4% to 9.5%) and 41.3% (95% CI 33.1% to 50.0%) relative increase in outpatient elective procedural volume. Outpatient procedural volume increased most significantly for hip replacement which was removed from the Inpatient Only List in 2020 (increase in outpatient surgical utilization of 589.3% (95% CI, 524.9% to 660.3%)). The shift to outpatient hip replacement procedures was concentrated among White patients; in 2021, hip replacement procedural volume increased by 271.1% (95% CI, 241.2% and 303.7%) for White patients and 29.5% (95% CI, 24.4% and 34.9%) for Black patients compared to 2019 levels. There were no consistent or large changes in 30-day complication, readmission, or mortality risk in 2020 and 2021 compared to 2019. There was a modest increase in elective outpatient surgeries and a pronounced increase in outpatient orthopedic surgeries which were removed from the Inpatient Only List during the COVID-19 pandemic. Utilization of outpatient surgical procedures was concentrated among White patients.

Preoperative MRSA screening using a simple questionnaire prior elective total joint replacement.

The purpose of this study was to evaluate the management and results of our standarized protocol for preoperative identification of MRSA colonisation in patients undergoing primary total hip and knee replacement procedures. Following hospital protocol, between January 2016 and June 2019 37,745 patients awaiting elective joint replacement underwent a standardized questionnaire to assess the risk of MRSA infection, identifying patients requiring preoperative MRSA screening. An evaluation of the questionnaire identified effective questions for identifying infected patients. Furthermore, an analysis evaluated the impact of comorbidities or Charlson Comorbidity Index scores on positive MRSA colonization. Additionally, we evaluated the cost savings of targeted testing compared to testing all surgery patients. Of the 37,745 patients, 8.057 (21.3%) were swabbed, with a total of 65 (0.81%) positive tests. From this group 27 (36.48%) who were treated were negative before surgery. Some of the questionnaire results were consistently associated with a higher chance of colonization, including hospitalization during the past year (47,7%), previous history of MRSA (44,6%), and agriculture or cattle farming related work (15,4%). By selectively testing high-risk patients identified through the questionnaire, we achieved a 79% reduction in costs compared to universal MRSA screening. Our results suggest that the simple and standardized questionnaire is a valuable tool for preoperative screening, effectively identifying high-risk patients prone to MRSA colonisation. The risk of periprosthetic joint infection (PJI) and its associated sequelae may be reduced by this approach.

Hip Implant Design using Stainless Steel 316L for Enhanced Stability and Patient Comfort

In a hip replacement procedure, the damaged bone and cartilage are removed and replaced with an artificial component known as prosthesis. Despite advancements in implant sterilization, design, fixation techniques, and the introduction of robotic surgery, a persistent challenge is to identify an optimal, patient-specific hip implant that meets individual criteria. The primary objective of the proposed study was to create a highly accurate patient-specific hip implant by standardizing the existing design. The secondary objective aimed to demonstrate the superiority of a customized design over a conventional one. Geometric measurements of the hip were extracted from CT scans using MIMICS 20.0 software, and the implant design was developed using SolidWorks. Finite Element Analysis (FEA) was employed for meshing and analyzing the planned implant. Comparative research through FEA analysis indicated that a customized implant made from SSL 13 material outperformed the standard implant, showcasing its suitability for the patients studied.

Vertical Versus Pfannenstiel Incision-Modified Stoppa Approach in the Treatment of Acetabular Fractures.

The aims of this study were to compare the patient and fracture characteristics, radiological, functional, and quality of life outcomes; the need for a lateral window approach and requirement of total hip arthroplasty; and complications in patients with simple and complex acetabular fractures who underwent a modified Stoppa approach through vertical and Pfannenstiel incisions. This was a retrospective comparison study. Level 1 trauma center. Patients with acetabular fractures (A-O-/-O-T-A type 62A-B-C) treated with vertical (group V) or Pfannenstiel (group P) incision-modified Stoppa approach between 2010 and 2020 were included. Patient characteristics, radiological evaluations (reduction quality and posttraumatic osteoarthritis), patient functional outcomes [12-item Short-Form Survey (SF-12) physical component score, SF-12 mental component score, Harris Hip Score, and Merle d'Aubigné-Postel], approach modifications and stratification by fracture type and complications were compared between those treated with vertical or Pfannenstiel incisions. One hundred four patients (mean age of 38.5 ± 14.3 years) were included. There was no significant difference between the Pfannenstiel or vertical groups regarding patient and fracture characteristics (P = 0.137), postoperative reduction quality (P = 0.130), or the mean functional and quality of life outcome scores at the last follow-up (P = 0.483 for the Harris Hip Score, P = 0.717 for the Merle d'Aubigné-Postel score, P = 0.682 for the SF-12 physical component score, and P = 0.781 for the SF-12 mental component score). In group P, significantly more patients needed additional lateral incisions (40.8% vs. 10.9%; P 0.001) and total hip replacement procedures (12.2% vs. 1.8%; P = 0.049). The total, early, and late complication rates were significantly higher in group P (P 0.001, P = 0.034, and P = 0.049, respectively). Pfannenstiel incision was associated with higher complication rates than vertical incision in acetabular fractures treated through a modified Stoppa approach. Fracture complexity is associated with the need for a lateral window approach and total hip arthroplasty, as well as a worse functional and radiological outcome regardless of incision type. However, it was not associated with the development of intraoperative or postoperative complications. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Unipolar Hip Hemiarthroplasty in Geriatric Patients: A Prospective Study and Analysis of Clinical and Radiological Outcomes.

Femoral neck fractures (FNF) in the geriatric population are commonly treated with hip replacement procedures, such as total hip arthroplasty, unipolar hip hemiarthroplasty (UHA), and bipolar hip hemiarthroplasty (BHA). The optimal treatment remains controversial, considering outcomes and cost-effectiveness, with UHA often being cheaper. This prospective observational study aims to evaluate UHA's clinical and radiological outcomes, safety, and survivorship compared to existing literature. We followed 90 elderly patients who underwent UHA following FNF. We assessed patients using the Parker score before and after surgery, as well as Harris Hip Score (HHS), and Postel-Merle d'Aubigné (PMA) scores postoperatively. All complications, acetabular erosions and heterotopic ossifications (HO), were documented. One year post-surgery, 26.7% of patients had passed away, mostly due to declining general health status. Systemic complications occurred in 14.4% of cases, with a 1.1% rate of deep surgical site infections. A single dislocation resulted from excessive stem anteversion. UHA implant survival rate was 97.8% after 4years. The Parker score remained stable, and HHS at 6 and 12months was 71.5 ± 12.9 and 70.9 ± 11.8, respectively, while PMA score was 14.3 ± 2.4 and 14.5 ± 2.1, respectively. Five hips showed Baker I acetabular wear. HO were noted as Brooker I in 12 patients, II in 4 patients, and IV in 1 patient. UHA exhibited comparable systemic complication rates, implant survivorship, and dislocation rates to those in the literature for both UHA and BHA. The deep surgical site infection rate was lower than reported for BHA. Patients' functional and mental abilities did not decline based on clinical scores. Acetabular wear in UHA was similar to its bipolar counterpart, while HO were only minor findings with no clinical implications. In elderly patients, UHA demonstrated clinical and radiological outcomes similar to BHA in existing literature. UHA may represent a cost-effective alternative for patients with limited life expectancy.

Evaluating Patient and Surgeon Characteristics Associated with Care Cost and Outcomes for Knee and Hip Replacement Procedures: A National Medicare Cohort Study.

The role of physician credentialing has been widely considered in quality and outcome improvement studies. However, the association between surgeon characteristics and health-care costs remains unclear. Our objective was to determine the association of orthopaedic surgeon characteristics with health outcomes and costs, utilizing Medicare data. We used 100% Fee-for-Service Medicare data from 2015 to 2019 to identify all patients ≥65 years of age who underwent 2 common orthopaedic surgical procedures, total hip and knee replacement. After determining whether the patients had been readmitted after discharge from their initial admission for surgery, we computed 3 metrics of total medical expenditure: the costs of the initial surgery admission and 30-day and 180-day episode-based bundles of care. Hierarchical linear regression and logistic regression models were used to evaluate patient and surgeon characteristics associated with care costs and the likelihood of readmission. We identified 2,269 surgeons who performed total knee replacements on 298,934 patients and 1,426 surgeons who performed total hip replacements on 204,721 patients. Patient characteristics associated with higher initial surgery costs included increasing age, female sex, racial minority status, and a higher Charlson Comorbidity Index. Surgeon characteristics associated with lower readmission rates included practice in the Northeast region and a higher patient volume; having malpractice claims was associated with higher readmission rates. A higher volume of patients treated by the orthopaedic surgeon was associated with lower overall costs and readmission rates. Information on surgeons' malpractice claims and annual volume should be made publicly available to assist patients, payer networks, and hospitals in surgeon selection and oversight. These results could also inform the guidelines of physician credentialing organizations. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Smart Design of Hip Replacement Prostheses Using Additive Manufacturing and Machine Learning Techniques

The field of additive manufacturing, particularly 3D printing, has ushered in a significant transformation in the realm of joint arthritis treatment through prosthetic surgery. This innovative technology allows for the creation of bespoke prosthetic devices that are tailored to meet the specific needs of individual patients. These devices are constructed using high-performance materials, including titanium and cobalt-chrome alloys. Nevertheless, the routine physical activities of patients, such as walking, sitting, and running, can induce wear and tear on the materials comprising these prosthetic devices, subsequently diminishing their functionality and durability. In response to this challenge, this research has endeavored to leverage novel techniques. The primary focus of this study lies in the development of an algorithm designed to optimize hip replacement procedures via the mechanical design of the prosthesis. This optimization process exploits the capabilities of machine learning algorithms, multi-body dynamics, and finite element method (FEM) simulations. The paramount innovation in this methodology is the capacity to design a prosthetic system that intricately adapts to the distinctive characteristics of each patient (weight, height, gait cycle). The primary objective of this research is to enhance the performance and longevity of prosthetic devices by improving their fatigue strength. The evaluation of load distribution on the prosthetic device, facilitated by FEM simulations, anticipates a substantial augmentation in the useful life of the prosthetic system. This research holds promise as a notable advancement in prosthetic technology, offering a more efficacious treatment option for patients suffering from joint arthritis. The aim of this research is to make meaningful contributions to the enhancement of patient quality of life and the long-term performance of prosthetic devices.

Postoperative Prevalence and Risk Factors for Serum Hypokalemia in Patients with Primary Total Joint Arthroplasty.

Regular monitoring of serum potassium after a total joint arthroplasty (TJA) is a form of routine examination that can help detect abnormal serum potassium levels and reduce the incidences of adverse events that may occur on account of postoperative hypokalemia. Previous studies rarely discussed hypokalemia after joint replacement. In the present study, our primary goal was to investigate the incidence and possible risk factors of hypokalemia after a total hip and knee replacement procedure was performed. This study included patients who underwent a unilateral total knee or hip arthroplasty in our department between April 2017 and March 2018. Serum potassium levels pre and post operation were collected and retrospectively analyzed. The differences in age, gender, body mass index (BMI), history of diseases, red blood cell (RBC), hemoglobin, hematocrit, glomerular filtration rate, ejection fraction, blood glucose, urine creatinine, urea nitrogen, intraoperative blood loss, operation time, drainage, preoperative potassium, surgery type, were compared between those patients diagnosed with hypokalemia and their non-hypokalemia at different times post surgery. Thereafter, the risk factors of postoperative hypokalemia patients were analyzed using statistical procedure multiple logistic regression model. The risk of hypokalemia after TJA was 53.1%, while, that on the first, third, and fifth day after operation was 12.5%, 40.7%, and 9.6% respectively. The serum potassium level on the first, third, and fifth postoperative days was 3.84 ± 0.32, 3.59 ± 0.34, and 3.80 ± 0.32 mmol/l, respectively. However, the level on the third day appeared to be the lowest (p = 0.015) of them all. The independent risk factors for hypokalemia after a total hip and knee replacement were the level of preoperative serum potassium concentration (p = 0.011), preoperative red blood cells counts (p = 0.027), and history of diabetes (p = 0.007). Regular monitoring of serum potassium concentration should be performed post TJA. We need to pay more attention to the patient's preoperative potassium levels along with their red blood cell counts especially in patients diagnosed with type 2 diabetes mellitus.

Frequent microbiological profile changes are seen in subsequent-revision hip and knee arthroplasty for prosthetic joint infection.

A proportion of patients with hip and knee prosthetic joint infection (PJI) undergo multiple revisions with the aim of eradicating infection and improving quality of life. The aim of this study was to describe the microbiology cultured from multiply revised hip and knee replacement procedures to guide antimicrobial therapy at the time of surgery. Patients and methods: Consecutive patients were retrospectively identified from databases at two specialist orthopaedic centres in the United Kingdom between 2011 and 2019. Patient were included who had undergone repeat-revision total knee replacement (TKR) or total hip replacement (THR) for infection, following an initial failed revision for infection. Results: A total of 106 patients were identified. Of these patients, 74 underwent revision TKR and 32 underwent revision THR. The mean age at first revision was 67years (SD 10). The Charlson comorbidity index was 2 for 31 patients, 3-4 for 57 patients, and 5 for 18 patients. All patients underwent at least two revisions, 73 patients received three, 47 patients received four, 31 patients received five, and 21 patients received at least six. After six revisions, 90 % of patients had different organisms cultured compared with the initial revision, and 53 % of organisms were multidrug resistant. The most frequent organisms at each revision were coagulase-negative Staphylococcus (36 %) and Staphylococcus aureus (19 %). Fungus was cultured from 3 % of revisions, and 21 % of infections were polymicrobial. Conclusion: Patients undergoing multiple revisions for PJI are highly likely to experience a change in organism, with 90 % of patients having a different organism cultured by their sixth revision. It is therefore important to administer empirical antibiotics at each subsequent revision, taking into account known drug resistance from previous cultures. Our results do not support the routine use of empirical antifungals.

Comprehensive Review on Biomaterials and Their Inherent Behaviors for Hip Repair Applications.

Developing biomaterials for hip prostheses is challenging and requires dedicated attention from researchers. Hip replacement is an inevitable and remarkable orthopedic therapy for enhancing the quality of patient life for those who have arthritis as well as trauma. Generally, five types of hip replacement procedures are successfully performed in the current medical market: total hip replacements, hip resurfacing, hemiarthroplasty, bipolar, and dual mobility systems. The average life span of artificial hip joints is about 15 years, and several studies have been conducted over the last 60 years to improve the performance and thereby increase the lifespan of artificial hip joints. Present-day prosthetic hip joints are linked to the wide availability of biomaterials. Metals, ceramics, and polymers are some of the most promising types of biomaterials; nevertheless, each biomaterial has advantages and disadvantages. Metals and ceramics fail in most applications owing to stress shielding and the emission of wear debris; ongoing research is being carried out to find a remedy to these unfavorable responses. Recent research found that polymers and composites based on polymers are significant alternative materials for artificial joints. With growing research and several biomaterials, recent reviews lag in effectively addressing hip implant materials' individual mechanical, tribological, and physiological behaviors. This Review comprehensively investigates the historical evolution of artificial hip replacement procedures and related biomaterials' mechanical, tribological, and biological characteristics. In addition, the most recent advances are also discussed to stimulate and guide future researchers as they seek more effective methods and synthesis of innovative biomaterials for hip arthroplasty application.

UK robotic arthroplasty clinical and cost effectiveness randomised controlled trial for hips (RACER-Hip): a study protocol

IntroductionThe number of robotic-assisted hip replacement procedures has expanded globally with the intended aim of improving outcomes. Intraoperative robotic-arm systems add additional costs to total hip replacement (THR) surgery but...

Sex-Specific Postoperative Outcomes of Primary Total Hip Replacements: The Performance of Total Hip Replacement Procedures Leads to Worse Outcomes in Men.

The demand for primary total hip arthroplasty (THA) is expected to increase significantly in the coming years, and women are expected to account for the greatest proportion of this increased demand. The purpose of this study was to determine, using a national database, the effect of sex on 90-day outcomes in primary THA patients while matching for confounding variables. Specifically, we evaluated: (1) in-hospital lengths of stay; (2) 90-day readmission rates; (3) 90-day medical complications; (4) and total global 90-day episode-of-care (EOC) costs in men and women. Using the 100% Medicare Standard Analytical Files (SAF), a query from January 1, 2005 to March 31, 2014 from a nationwide database was performed to analyze patients who received a primary THA. The series was divided into two cohorts: men (n=436,737) and women (n=436,737). Male and female patients were matched according to age and Elixhauser-Comorbidity Index (ECI). Uni- and multi-variable regression analyses were performed to analyze the effects of sex on in-hospital lengths of stay, 90-day readmission rates, 90-day medical complications, and total global 90-day EOC costs. Men had greater overall 90-day medical complications compared to women following primary THA (1.28 vs. 1.19%, p<0.001). Men were found to have higher rates of acute kidney failure (0.12 vs 0.05%, p<0.0001), acute pancreatitis (0.02 vs. 0.01%, p<0.0001), cerebrovascular accidents (0.03 vs. 0.01%, p<0.0001), deep vein thromboses (0.06 vs. 0.04%, p<0.0001), and myocardial infarctions (0.02 vs. 0.01%, p<0.0001). Women were found to have higher rates of acute post-hemorrhagic anemiae (0.31 vs. 0.30%, p<0.001) and urinary tract infections (UTI; 0.40 vs. 0.28%, p<0.0001) compared to men. Men had shorter in-hospital lengths of stay (LOS) (3.42 vs. 3.54 days, p<0.001) but greater 90-day readmission rates (7.67 vs. 6.39% p<0.0001). Both cohorts had similar total global 90-day EOC costs ($14,869.85 ± $12,333.50 vs. $14,957.34 ± $10,915.61, p=0.36). Men undergoing THA have a greater number of overall 90-day medical complications and readmission rates while women have higher incidence of UTI, post-hemorrhagic anemia, and longer LOS. Understanding sex-based differences in complication rates and outcomes can help surgeons with preoperative counseling and targeted preoperative optimization.

Femoral neck version in the spinopelvic and lower limb 3D alignment: a full-body EOS® study in 400 healthy subjects.

The goal of this study was to better understand the variation of femoral neck version according to spinopelvic and lower limb 3D alignment using biplanar X-rays in standing position. This multicentric study retrospectively included healthy subjects from previous studies who had free-standing position biplanar radiographs. Subjects were excluded if they presented spinal or any musculo-skeletal deformity, and reported pain in the spine, hip or knee. Age, sex, and the following 3D-reconstructed parameters were collected: spinal curvatures, pelvic parameters, sagittal vertical axis (SVA), T1 pelvic angle (TPA), spino-sacral angle (SSA), femoral torsion angle (FTA), sacro-femoral angle (SFA), knee flexion angle (KA), ankle angle (AA), pelvic shift (PS) and ankle distance. Femoral neck version angle (FVA) was calculated between horizontal plane projection of the bi-coxo-femoral axis and the line passing through the femoral neck barycenter and femoral head center. Analysis according to age subsets was performed. A total of 400 subjects were included (219 females); mean age was 29 ± 18years (range: 4-83). Subjects with high pelvic tilt values presented significantly higher FVA than average and low-PT individuals, respectively, 7.8 ± 7.1°, 2 ± 9° and 2.1 ± 9.5° (p < 0.001). These subjects also presented lower lumbar lordosis values and higher acetabulum anteversion in the horizontal plane than the two other groups. SVA correlation with FVA was weaker (r = 0.1, p = 0.03) than SSA and TPA (r = - 0.3 and r = 0.3, respectively, p < 0.001). A strong correlation was found with femoral torsion (r = 0.5, p < 0.001). SFA (r = - 0.3, p < 0.001), pelvic shift (r = 0.2, p < 0.001) and ankle distance (r = 0.3, p < 0.001) were also significantly correlated. Multivariate analysis confirmed significant association of age, pelvic tilt, lumbar lordosis, pelvic shift, ankle distance and femoral torsion with FVA. Patients with lower lumbar lordosis present pelvic retroversion which induces a higher femoral neck version. This finding may help positioning implants in total hip replacement procedures. Higher pelvic shift, age, male gender and increased femoral torsion were also correlated with higher FVA. II (Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding).