Aims. Current diagnostic tools are not always able to effectively identify periprosthetic joint infections (PJIs). Recent studies suggest that circulating microRNAs (miRNAs) undergo changes under pathological conditions such as infection. The aim of this study was to analyze miRNA expression in hip arthroplasty PJI patients. Methods. This was a prospective pilot study, including 24 patients divided into three groups, with eight patients each undergoing revision of their hip arthroplasty due to aseptic reasons, and low- and high-grade PJI, respectively. The number of intraoperative samples and the incidence of positive cultures were recorded for each patient. Additionally, venous blood samples and periarticular tissue samples were collected from each patient to determine miRNA expressions between the groups. MiRNA screening was performed by small RNA-sequencing using the miRNA next generation sequencing (NGS) discovery (miND) pipeline. Results. Overall, several miRNAs in plasma and tissue were identified to be progressively deregulated according to ongoing PJI. When comparing the plasma samples, patients with a high-grade infection showed significantly higher expression levels for hsa-miR-21-3p, hsa-miR-1290, and hsa-miR-4488, and lower expression levels for hsa-miR-130a-3p and hsa-miR-451a compared to the aseptic group. Furthermore, the high-grade group showed a significantly higher regulated expression level of hsa-miR-1260a and lower expression levels for hsa-miR-26a-5p, hsa-miR-26b-5p, hsa-miR-148b-5p, hsa-miR-301a-3p, hsa-miR-451a, and hsa-miR-454-3p compared to the low-grade group. No significant differences were found between the low-grade and aseptic groups. When comparing the tissue samples, the high-grade group showed significantly higher expression levels for 23 different miRNAs and lower expression levels for hsa-miR-2110 and hsa-miR-3200-3p compared to the aseptic group. No significant differences were found in miRNA expression between the high- and low-grade groups, as well as between the low-grade and aseptic groups. Conclusion. With this prospective pilot study, we were able to identify a circulating miRNA signature correlating with high-grade PJI compared to aseptic patients undergoing hip arthroplasty revision. Our data contribute to establishing miRNA signatures as potential novel diagnostic and prognostic biomarkers for PJI. Cite this article: Bone Jt Open 2024;5(6):479–488

Background. Tranexamic acid (TXA) decreases blood loss and therefore, may minimize painful postoperative hematomas after total hip arthroplasty (THA). This study evaluated early postoperative pain and blood loss in THA patients with and without the use of topical TXA. Methods. A consecutive series of 174 THAs performed without TXA were compared to a consecutive series of 156 THAs performed with topical TXA. Procedures were performed by a single surgeon using identical perioperative medical and pain control protocols. Inpatient pain scores (VAS 0 to 10), opioid consumption (morphine equivalents, Meq), time to first opioid, and drop in hemoglobin (Hgb) were evaluated. Univariate analysis of topical TXA and 20 potential covariates of pain and blood loss was performed, followed by logistic and linear regression with p≤0.250. Results. In multivariate analysis, THAs with TXA were independently associated with less hemoglobin loss than THAs without TXA (2.98 g/dL vs. 3.39 g/dL; p=0.001). Topical TXA use was associated with greater pain (3.41 vs. 1.71, p=0.001) and increased opioid consumption (44.2 vs. 24.2 Meqs, p<0.001) during the first 24 hours, and decreased time to first opioid (182 vs 422 minutes, p=0.008). 33% of patients receiving TXA compared to 9% without TXA reported moderate-severe pain (p=0.021). Preoperative narcotic use (p=0.055 to 0.008) and fentanyl rather than morphine spinals (p=0.034 to 0.008) also independently increased postoperative pain. Conclusion. Findings continue to support TXA in minimizing blood loss in THA; however, increased early postoperative pain with topical TXA was an unexpected discovery. This finding is reinforced by TXA affecting GABA and glycine receptors in the spinal dorsal horn, and TXA causing periarticular cell death in vivo at clinical concentrations. We currently avoid topical TXA use clinically, particularly in the outpatient early discharge setting, and are exploring whether similar findings are observed with intravenous TXA. For any tables or figures, please contact the authors directly

Now that periprosthetic osteolysis is under control, analyzing how it was overcome has substantial value. What can we learn about how to attack the next enigma? There were six important generic drivers leading to that success:. Surmounting the failure to recognize its full nature. Why was it that the lapse between the first case and the publication of the article called “cement disease” was three decades? In part, because the concept of “cement disease” was simultaneously ingenious, essential, incomplete and misleading. Understanding “biology beyond the histology.” Histology assured us that this destruction process was not malignant but well beyond that was discovery of the novel and exquisite understanding of the molecular biology. The importance of multiple parallel approaches. The detailed molecular biology suggested that a pharmacologic prophylaxis should exist, but none was ever found. Of the three possible alternate bearings, the most likely (metal-on-metal) failed badly and the least likely (metal-on-polyethylene) succeeded. The critical role of “beyond luck.” It is essential to understand more fully that serendipity nearly always follows Pasteur's motto that “chance favors only the prepared mind.”. The irreplaceable role of persistence. This is almost a homily. The unavoidable requirement of risk-taking. Forty years of metal-on-metal THA without pseudotumors provided no protection against its current ravages

Aims

Although the Fitmore Hip Stem has been on the market for almost 15 years, it is still not well documented in randomized controlled trials. This study compares the Fitmore stem with the CementLeSs (CLS) in several different clinical and radiological aspects. The hypothesis is that there will be no difference in outcome between stems.

Introduction. Periprosthetic osteolysis resulting in aseptic loosening is a leading cause for total hip arthroplasty (THA) failure. Individuals vary in their susceptibility to osteolysis, and it is thought that heritable factors contribute to this variation. We conducted two genome-wide association studies to identify genetic risk loci associated with osteolysis and genetic risk loci associated with time to prosthesis failure due to osteolysis. Patients/Materials & Methods. The Norway cohort comprised 2,624 subjects after THA recruited from the Norwegian Arthroplasty Registry, 779 with revision surgery for osteolysis. The UK cohort comprised 890 subjects recruited from hospitals in the north of England, 317 with radiographic evidence or revision surgery for osteolysis. All subjects had received a fully cemented or hybrid THA using small-diameter metal or ceramic-on-conventional polyethylene bearing. Osteolysis susceptibility case-control analyses and quantitative trait analyses for time to prosthesis failure were undertaken after genome-wide genotyping. Finally, a meta-analysis of the discovery datasets was undertaken. Results. Genome-wide association analysis identified 4 and 11 independent suggestive genetic signals for osteolysis susceptibility at P≤5×10. −6. in the Norwegian and UK cohorts, respectively. Following meta-analysis, 5 independent genetic signals showed suggestive association with osteolysis at P≤5×10. −6. , with the strongest comprising 18 correlated variants on chromosome 7 (lead signal rs850092, Figure 1, p=1.13×10. −6. ). Genome-wide quantitative trait analysis in cases only showed a total of 5 and 9 independent genetic signals for time to prosthesis failure at P≤5×10. −6. , respectively. Following meta-analysis, 11 independent genetic signals showed suggestive evidence of association with time to failure at P≤5×10. −6. , with the largest association block comprising 174 correlated variants in chromosome 15 (lead signal rs10507055, Figure 2, p=1.40×10. −7. ). Discussion. These studies provide the first genome-wide insights into the heritable biology of osteolysis, a major complication of joint replacement surgery. Although there were no dominant signals of genome-wide significance, we find replicating evidence for several independent genetic loci both for osteolysis susceptibility and time to prosthesis failure at P≤5×10. −6. , consistent with the complex aetiology of the disease. Conclusion. The heritable contribution to osteolysis is modest. The identified genetic loci may however provide novel avenues for therapy development in this condition. For any figures and tables, please contact the authors directly

Aims

This study aims to answer the following questions in patients with hip osteoarthritis (OA) who underwent total hip arthroplasty (THA): are patient-reported outcome measures (PROMs) affected by the location of the maximum severity of pain?; are PROMs affected by the presence of non-groin pain?; are PROMs affected by the severity of pain?; and are PROMs affected by the number of pain locations?

Aims

This study was designed to develop a model for predicting bone mineral density (BMD) loss of the femur after total hip arthroplasty (THA) using artificial intelligence (AI), and to identify factors that influence the prediction. Additionally, we virtually examined the efficacy of administration of bisphosphonate for cases with severe BMD loss based on the predictive model.

Aims

Precise implant positioning, tailored to individual spinopelvic biomechanics and phenotype, is paramount for stability in total hip arthroplasty (THA). Despite a few studies on instability prediction, there is a notable gap in research utilizing artificial intelligence (AI). The objective of our pilot study was to evaluate the feasibility of developing an AI algorithm tailored to individual spinopelvic mechanics and patient phenotype for predicting impingement.

Aims

Total hip arthroplasty (THA) is a common procedure to address pain and enhance function in hip disorders such as osteoarthritis. Despite its success, postoperative patient recovery exhibits considerable heterogeneity. This study aimed to investigate whether patients follow distinct pain trajectories following THA and identify the patient characteristics linked to suboptimal trajectories.

Introduction. Although DDH is one of the most common skeletal dysplasias (incidence 1.5 cases per 1000 births), it remains slow and costly to recruit large-scale patient cohorts for powerful genetic association studies. In this work we have successfully used the NJR as a platform to generate a DDH biobank of 907 individuals, upon which we have conducted the first ever genome-wide association study (GWAS) for DDH. Methods. 5411 patients recorded as having a hip replacement for ‘hip dysplasia’ between March 2003 and December 2013 were approached to participate in the study. Following filtering by questionnaire for non-DDH cases and non-European Caucasians, 907 patients returned a completed saliva sample. A randomly selected sample of individuals participating on the UK Household Longitudinal Study that had been previously genotyped using the same platform were used as controls at a case:control ratio of 1:4. A further data set consisting of 332 cases, 1375 controls and 26 variants was used to replicate the top signals. Results. Of 256833 variants that passed QC, 11 variants reached genome-wide significance. All these variants came from the same signal, with rs143384 as the index SNP (allele A, allele frequency 0.60, OR [95% CI] 1.58[1.40–1.77], P=1.1×10. −14. ). Twenty-six independent variants were prioritized to follow up through de novo replication. Variant rs143384 was found to be significantly associated with DDH after meta-analysing discovery and replication datasets (allele A, allele frequency 0.60, OR [95% CI] 1.50[1.36–1.66], P=2.81×10. −16. ). Discussion. Using eHR case-ascertainment and distance recruitment strategies we conducted the first GWAS for DDH and confirmed association of the GDF5 variant rs143384 with DDH (P=2.81×10. −16. ). We establish the first genome-wide significant locus for DDH, discovered through linking EHRs with genomics as a proof of principle in enabling powerful genetic association studies of relatively rare but complex diseases

Aims

The aim of this study was to compare the mid-term patient-reported outcome, bone remodelling, and migration of a short stem (Collum Femoris Preserving; CFP) with a conventional uncemented stem (Corail).

Louis Pasteur once said that: “Fortune favours the prepared mind.” As one of the great scientists who contributed to the fight against infection, he emphasised the importance of being prepared at all times to recognise infection and deal with it. Despite the many scientific discoveries and technological advances, such as the advent of antibiotics and the use of sterile techniques, infection continues to be a problem that haunts orthopaedic surgeons and inflicts suffering on patients. . The medical community has implemented many practices with the intention of preventing infection and treating it effectively when it occurs. Although high-level evidence may support some of these practices, many are based on little to no scientific foundation. Thus, around the world, there is great variation in practices for the prevention and management of periprosthetic joint infection. This paper summaries the instigation, conduct and findings of a recent International Consensus Meeting on Surgical Site and Periprosthetic Joint Infection. . Cite this article: Bone Joint J 2013;95-B:1450–2

Introduction. Hip Osteoarthritis (HOA) is a highly heterogeneous disease with potentially different genetic aetiologies. Thus far, few genetic variants have been robustly associated with broad definitions of HOA. We aimed to identify novel HOA susceptibility variants by examining a set of more homogeneous, radiographically-derived endophenotypes relating to anatomic pattern of joint involvement and bone remodelling response in HOA. Materials, Methods and Results. Individuals with HOA and AP-hip radiographs (n=2,109) were selected from the arcOGEN study, genotyped on 2 platforms. The most arthritic hip per patient was categorised using Bombelli's classification (atrophic/normotrophic/hypertrophic), and for pattern of joint space narrowing (superior/medial-axial/concentric). Following 1000-Genomes-Project-based imputation and stringent quality control over 7 million variants were tested for association with each phenotype under the additive model. Fixed-effects meta-analysis was used to combine the results from the two GWA studies. In the discovery GWAS of atrophic HOA vs cases with non-atrophic HOA a strong signal (rs16869403, OR[95% CI]=2.47[1.81–3.38], p=1.53×10. −8. ) was detected in the G protein-coupled receptor, GPR98. Polymorphisms in GPR98 have been associated with osteoporotic fracture and low bone mineral density and GPR98 knockout mice have a low bone mass phenotype. The meta-analysis of medial joint space narrowing showed strong association with variants in LRCH1 (rs754106, OR[95% CI]=1.46[1.26–1.68], P=2.85×10. −7. ) previously associated with OA but with conflicting replication evidence, and BMP1 (chr8:22065846, OR[95% CI]=3.36[2.12–5.33], P=2.6×10. −7. ) which induces bone and cartilage development. None of these variants showed significant evidence for association when broadly classified HOA cases were compared to population-based controls from the arcOGEN GWAS. Conclusion. Through comprehensive examination of radiographically-derived, HOA-related phenotypes we have identified several promising signals that point to novel biologically plausible genes for HOA. Our results indicate that, in a heterogeneous disease like OA the study of narrower phenotype definitions closer to the biology of the disease has the potential to enhance power to detect OA-relevant associations

Introduction. Aseptic loosening, the clinical endpoint of osteolysis, remains the leading cause of total hip arthroplasty (THA) failure, and is caused by a host response to wear debris that varies between individuals. Although several candidate gene studies have identified loci associated with osteolysis susceptibility, there have been no systematic studies at genome-wide level. We aimed to identify risk loci associated with osteolysis by conducting a genome-wide association study. Methods. 3,706 Caucasian European patients following THA were studied. The discovery cohort comprising 894 patients (317 with osteolysis) were genotyped using the Illumina-610 beadchip followed by 1000 Genome-based imputation covering 10 million single nucleotide polymorphisms (SNPs). Phenotypes were transformed to normality where required, regressed on important covariates and z-standardised. Following quality control, osteolysis case-control analysis and a quantitative trait association analysis for time to prosthesis failure were undertaken. Index SNPs p<9×10. −4. were taken forward for replication in a second cohort comprising 2,812 subjects (834 osteolysis cases) recruited from the Norwegian arthroplasty registry. Genotyping was undertaken using Sequenom MassARRAY iPLEX Gold assay and association analyses undertaken using logistic and linear regression. Summary statistics were combined in a fixed-effects meta-analysis framework. Results. The strongest signal associated with time to prosthesis failure lay within DEFB129 gene. The signal index SNP, rs6105394, approached genome wide significance at p=5.75×10. −7. Two signals in the susceptibility analysis also approached genome-wide significance, 1 within CAMK4 (rs306105, OR 0.41, p=6.54×10. −7. ) and 1 upstream of PLNXA2 (rs11119057, OR 0.96, p=6.44×10. −7. ). Following meta-analysis, the strongest signal in the susceptibility analysis remained that within CAMK4 (rs306105, p=3.79×10. −4. ). The strongest signal associated with time to failure was just upstream of CNTN3 (rs1374879, p=2.15×10. −5. ). Discussion. We have identified promising loci associated with osteolysis and time to prosthesis failure although not at genome-wide significance (p<5×10. −8. ). In order to further validate these loci, larger genome wide association analysis is required

Aims

Periprosthetic joint infections (PJIs) with prior multiple failed surgery for reinfection represent a huge challenge for surgeons because of poor vascular supply and biofilm formation. This study aims to determine the results of single-stage revision using intra-articular antibiotic infusion in treating this condition.

The unparalleled events of the year 2020 continue to evolve and challenge the worldwide community on a daily basis. The COVID-19 pandemic has had a major impact on all aspects of our lives, and has caused major morbidity and mortality around the globe. The impact of COVID-19 on the practice of orthopedic surgery has been substantial with practice shutdowns, elective surgery restrictions, heightened utilization of telemedicine platforms and implementation of precautionary measures for in-person clinic visits. During this transition period the scholarly and educational pursuits of academic surgeons have been de-emphasized as the more immediate demands of clinical practice survivorship have been the priority. This unavoidable focus on clinical practice has heightened the importance of orthopedic subspecialty societies in maintaining an appropriate level of attention on research and educational activities. Under the outstanding presidential leadership of Robert Barrack, MD, The Hip Society adapted to the profound challenges of 2020, and maintained strong leadership in the realms of education and research. The recent 2020 summer meeting of the Hip Society was a testimonial to the resilience and dedication of the Society members to ongoing innovation in research and education. Due to travel and social distancing restrictions the 2020 summer meeting was transitioned from an in-person to a virtual meeting format. Dr Barrack and Program Chair Dr John Clohisy assisted with oversight of the meeting, while Olga Foley and Cynthia Garcia ensured the success of the meeting with remarkable planning and organization. These collaborative efforts resulted in an organized, well-attended, high level scientific meeting with engaging discussion and a remarkable virtual conference environment. The Bone & Joint Journal is very pleased to partner with The Hip Society to publish the proceedings of this very unique virtual meeting. The Hip Society is based in the United States and membership is granted to select individuals for leadership accomplishments in education and research related to hip disease. The Society is focused on the mission of advancing the knowledge and treatment of hip disorders to improve the lives of patients. The vision of the Hip Society is to lead in the discovery and dissemination of knowledge related to disorders of the hip. The annual closed meeting is one of the most important events of the society as this gathering highlights timely, controversial and novel research contributions from the membership. The top research papers from The Hip Society meeting will be published and made available to the wider orthopedic community in The Bone & Joint Journal. This partnership with The Bone & Joint Journal enhances the mission and vision of The Hip Society by international dissemination of the meeting proceedings. Given the far-reaching circulation of The Bone & Joint Journal the highest quality work is available to an expanding body of surgeons, associated healthcare providers and patients. Ultimately, this facilitates the overarching Hip Society goal of improving the lives of our patients. The 2020 virtual Hip Society meeting was characterized by outstanding member attendance, high quality paper presentations and robust discussion sessions. The meeting was held over two days and encompassed 58 open paper presentations divided into ten sessions with moderated discussions after each session. All papers will be presented in this issue in abstract form, while selected full papers passing our rigorous peer review process will be available online and in The Bone & Joint Journal in a dedicated supplement in 2021. The first session of the meeting focused on issues related to complex primary THA and osteonecrosis of the femoral head. Dr Gross presented on the conversion of hip fusion to THA in 28 patents at a mean 7 years. He reported a high clinical success rate, yet complications of heterotopic ossification and neurologic injury were relatively common. Consideration of heterotopic ossification prophylaxis and the selective use of a constrained liner were recommended. Dr Pagnano summarized the use of various contemporary porous acetabular components in 38 hips in the setting of prior pelvic radiation. The mean follow-up was 5 years and 10 year survivorship was 100% with all implants radiographically fixed. Dr Bolognesi's study demonstrated that THA in solid organ transplant patients is associated with higher risk for facility placement, transfusions and readmissions. This patient population also has increased mortality risk (4.3% risk at 1 year) especially lung transplant patients. The second group of papers focused on femoral head osteonecrosis. Dr Iorio presented single center data demonstrating that CT scan was a useful adjunct for diagnosis in the staging work-up for cancer, yet was not useful for ARCO staging and treatment decision-making. On the basic science side, Dr Goodman utilized a rabbit model of steroid-induced femoral head osteonecrosis to determine that immunomodulation with IL-4 has the potential to improve bone healing after core decompression. The session was concluded by Dr Nelson's study of ceramic-on-ceramic THA in 108 osteonecrosis patients. The median 12 year results were outstanding with marked increases in PROs, maintenance of high activity levels, and a 3.7% revision rate. In the second session attention was directed to THA instability and spinopelvic mobility. Dr Sierra presented a machine learning algorithm for THA dislocation risk. Two modifiable variables (anterior/lateral approach, elevated liner) were most influential in minimizing dislocation risk. Dr Taunton's study demonstrated a deep learning artificial intelligence model derived from postoperative radiographs to predict THA dislocation risk. High sensitivity and negative predictive value suggest that this model may be helpful in assessing postoperative dislocation risk. In reviewing a large single-center, multiple surgeon cohort of 2,831 DAA procedures, Dr Moskal noted a very low dislocation rate (0.45%) at minimum 2 years. Importantly, spinopelvic pathology or prior spinal instrumentation was not associated with an increased dislocation risk (0.30%). Dr Huo and colleagues analyzed pelvic tilt during functional gait in patients with acetabular dysplasia. They detected variable pelvic tilt on different surfaces with the data suggesting that patients with more anterior pelvic tilt while standing tend to have greater compensatory posterior pelvic tilt during gait. Dr Lamontagne reported on the sagittal and axial spinomobility in patients with hip OA, and highlighted reductions in pelvic tilt, pelvic-femoral-angle, lumbar lordosis and seated maximal trunk rotation when compared to controls. Dr Dennis showed that differences in spinopelvic mobility may explain the variable accuracy of acetabular version measurements on the cross-table lateral radiographs. Dr Gwo-Chin presented on a comprehensive functional analysis of 1,592 patients undergoing THA and observed that spinopelvic abnormalities are not infrequent (14%) in THA patients. Consistent with these findings Dr Murphy and collaborators identified a low prevalence of previous spinal instrumentation (1.5%), yet a high prevalence of spine stiffness (27.6%) in 149 patients undergoing THA. Session three highlighted various aspects of treating hip disease in young patients. Dr Peters investigated the need for subsequent hip arthroscopy in 272 patients treated with an isolated PAO. Only 4.8% of these patients required subsequent arthroscopy calling into question the routine use of combined arthroscopy and PAO. Three papers addressed questions related to THA in young patients. Dr Berend's study of 2532 hips demonstrated that high activity level was not associated with an increased risk of midterm aseptic or all cause failure. Dr Nunley presented on 43 young patients with an average age of 52 years treated with a cementless stem and modular dual mobility articulation. Stress shielding was minimal and no concerning metal ion release detected. Dr Garvin summarized minimum 15 year data of THA with highly cross-linked polyethylene in patient less than 50 years. These hips performed exceptionally well with no mechanical loosening or radiographic osteolysis. Dr Engh examined 10 year results of the Birmingham Hip Resurfacing implant and reported a 92.9 % overall survivorship, with males less than 55 years achieving a 98.3% survivorship. The session was concluded by long-term data on the Conserve Plus hip resurfacing arthroplasty. Dr Amstutz presented an impressive dataset depicting an 83.1% 20 year survivorship for this early resurfacing cohort. Direct anterior approach total hip arthroplasty was the focus of session four. Dr Meneghini reported on the anesthesia and surgical times of direct anterior and posterior approaches from a large healthcare system database. These data suggested longer OR and surgical times for the DAA both in the inpatient and ASC environments. Dr Clohisy introduced the technique and early outcomes of lateral decubitus position DAA. In a learning curve experience of 257 hips. 96% of acetabular components were in the Lewinneck safe zone, the aseptic revision rate was 0.9% and there were no dislocations. Dr Beaule analyzed femoral stem cement mantle with the DAA and posterior approaches by comparing two matched cohorts. Stem alignment and cement mantle quality were equivalent with both approaches. Similarly, Dr Emerson demonstrated technical feasibility and fewer cemented femoral stem failures when compared to cementless stems in a series of 360 DAAs THAs. The final paper of the session presented by Dr Hamilton examined the impact of surgical approach on dislocation after isolated head and liner exchange. Neither the posterior nor the anterior approach was superior in reducing the dislocation rate for these high dislocation risk procedures. The fifth session explored contemporary topics related to anesthesia and pain management. Dr Byrd opened the session with a comparative study evaluating general versus spinal anesthesia for hip arthroscopy. This preliminary study was provoked by the desire to minimize aerosolized exposure early in the COVID-19 pandemic by transitioning to spinal anesthesia. Both anesthetic methods were effective. Dr Austin presented a randomized, double-blind controlled trial comparing spinal anesthetic with mepivacaine, hyperbaric bupivacaine and isobaric bupivacaine. Mepivacaine patients ambulated earlier and were more likely to be discharged the same day. Dr Mont provided a very timely study on the effects of “cannabis use disorder” and THA outcomes. This administrative database study of 44,154 patients revealed this disorder to be associated with longer hospital stays, increased complications rates and higher costs. Dr Bedair investigated whether a highly porous acetabular component submerged in an analgesic solution could enhance perioperative pain management. Interestingly, this novel strategy was associated with a reduction of postoperative pain scores and opioid consumption in 100 experimental patients compared to 100 controls. The concluding paper of the session by Dr Della Valle examined whether decreased discharge opioids led to increased postoperative opioid refills. A large single-center study of 19,428 patients detected a slight increase (5%) in opioid refills but a reduction in total refill morphine milligram equivalents. The final, sixth session of day one considered various challenging aspects of revision hip arthroplasty. Dr Nam started the session with review of preliminary results from a randomized control trial comparing closed incision negative-pressure therapy with a silver-impregnated dressing for wound management in 113 hips undergoing revision arthroplasty. Unlike previous reports, the negative pressure therapy was associated with a higher reoperation rate for wound-related complications. Dr Bostrom highlighted the potential clinical impact of basic biological interventions by establishing the presence of Neutrophil Extracellular Traps (NETS) in fibrotic tissue from human aseptic loosening specimens and in a murine model of unstable tibial implantation. NET inhibition in the murine model prevented the expected tibial implant osseointegration failure. Dr Lombardi presented early 3.3 year clinical results of a highly porous Ti6al4v acetabular component in complex primary and revision arthroplasty. Survivorship for aseptic loosening was 96.6 % and 95.3% for the primary and revision cases, respectively. Dr Schwarzkopf and colleagues explored the impact of time to revision arthroplasty on clinical outcomes. Analysis of 188 revision cases revealed early revisions (less than 2 years from primary) were associated with worse outcomes, longer hospitalizations and higher reoperation rates. Mid-term results for modular dual mobility implants in revision arthroplasty were reviewed by Dr Lachiewicz who reported on 126 hips at a mean 5.5 years. 11% of hips dislocated and the 6 year survival was 91%. An outer head diameter of 48mm or greater was associated with a lower risk of dislocation. Dr Berry concluded the session by discussing the outcomes of treating the challenging problem of interprosthetic femur fractures. A single-center study of 77 cases treated over 32 years demonstrated a 79% success rate free of reoperation at 2 years with 95% of patients being ambulatory. The second day commenced with the seventh session evaluating recent strategies to improve short-term THA outcomes. Dr Bozic and colleagues investigated the association of quality measure public reporting with hip/knee replacement outcomes. Annual trend data from 2010–2011 and 2016–2017 indicate that hospital-level complication and readmission rates decease after the start of public reporting, yet it is difficult to prove a direct effect. Dr Slover reviewed his institutions experience with the Comprehensive Care for Joint Replacement (CJR) model and emphasized that lower CJR target prices make it increasingly difficult for programs to meet target price thresholds. Cost saving strategies including same day discharge and reduction of home health services may result in smaller losses of positive margins. Dr Barsoum reported on the influence of patient and procedure-related risk factors of length of stay after THA. Patient-related risk factors provided substantial predictive value yet procedure-related risk factors (hospital site and surgical approach) remain the main drivers of predicting length of stay. Dr Hozack reviewed an impressive, single surgeon cohort of 3,977 DAA THAs and analyzed adverse events and 90 day perioperative outcomes. Simultaneous bilateral DAA THA was comparable with unilateral or staged bilateral procedures in regards to complications, readmission rate and home discharge rate but with an increased risk of transfusion. To examine the risk of complications with outpatient joint arthroplasty, Dr Della Valle performed a single-surgeon matched cohort analysis comparing outpatient and inpatient hip and knee arthroplasties. Outpatient procedures were not associated with an increased risk of any postoperative complications and actually experienced fewer emergency department visits. The eighth session covered various contemporary challenges in hip arthroplasty care. Dr Griffin began the session with an analysis of the timing of complications associated with two-stage exchange procedures for periprosthetic joint infection (PJI). Of the 189 hips included, 41.6% had a complication and the mortality was 14.1% at 2.5 years, highlighting the morbidity of this treatment method. Dr Fehring provided data assessing the fate of two-stage reimplantation after failed debridement, antibiotics and implant retention (DAIR) for a prosthetic hip infection. This analysis of 114 hips yielded concerning results demonstrating a 42.9% treatment failure of patients treated with a previous DAIR compared to a 12.3% failure rate in patients treated with an initial 2-stage procedure. Dr Jacobs reviewed the analysis of 106 femoral heads with severe corrosion and identified a chemically dominated etching process termed “column damage” to be a detrimental damage mode within CoCr femoral heads that is directly linked to banding within its microstructure. These data indicate that implant alloy microstructure must be optimized to minimize the release of fretting-corrosion products. Simon Mears presented retrospective data from 184 THAs with a dual modular femoral stem. A subgroup of hips with a modular, cobalt chromium femoral neck had a pseudotumor visualized in 15% with only 55% of these having elevated CoCr levels. These findings may support the use of routine follow-up MARS MRI for modular CoCr femoral neck prostheses. The final two studies explored timely issues related to viral illness and hip surgery. Dr Browne analyzed three large administrative databases to elucidate whether patients are at increased risk for viral illnesses following total joint replacement. The incidence of postoperative influenza after total joint replacement was not increased compared to patients not undergoing total joint replacement surgery suggesting that arthroplasty procedures may not heighten the risk of viral illness. In the final paper of the session Dr Haddad presented important data regarding perioperative complications in coronavirus positive patients undergoing surgical treatment of femoral neck fractures. In this multicenter cohort study from the United Kingdom 82 coronavirus positive patients were shown to have longer hospital stays, more critical care unit admissions, higher risk of perioperative complications and an increased mortality compared to 340 coronavirus negative patients. The eighth session had two papers on alternative femoral stem designs and three presentations more focused on femoral fracture treatments. Dr Mihalko focused on the European and US experiences with the Metha femoral neck retaining stem. The US experience mirrored the encouraging results from Europe with a 94% all cause femoral survivorship and a 99.1% femoral aseptic loosening survivorship at 5 years. Dr Kraay summarized dual energy x-ray absorptiometry (DEXA) evaluation of 16 low modulus composite femoral components at long-term follow-up of a mean 22 years. The bone mineral density associated with the implant increased in Gruen zones 2–6 and showed limited decreases in zones 1 and 7. These data support the concept that a low modulus femoral stem may more effectively load the proximal femur. Dr Springer provided data from the American Joint Replacement Registry (AJRR) and by evaluating outcomes of exact matched cohorts of 17,138 patients treated with cementless or cemented femoral implants for femoral neck fractures. Cemented implants were associated with marked reduction in early revision and periprosthetic fractures. However, cemented fixation was associated with an increased mortality at 90 days and 1 year. Additional data from the AJRR was presented by Dr Huddleston who investigated the risk factors for revision surgery after arthroplasty in a cohort of 75,333 femoral neck fractures. THA when compared to hemiarthroplasty was associated with higher early and overall revision rates. Cementless femoral fixation and increased age were also associated with higher rates of any revision. Both of these studies from the AJRR suggest that further consideration should be given to femoral fixation preferences in the femoral neck fracture population. Dr Vail summarized his institution's experience with an interdisciplinary hip fracture protocol for patients undergoing arthroplasty for acute femoral neck fractures. His study compared 157 cases prior to protocol implementation with 114 patients treated after the protocol was established. The impact of the interdisciplinary protocol was impressive as evidenced by a reduced time to operative treatment, length of stay, complication rate and one-year mortality. All being achieved without an increase in readmissions or facility discharges. The final session of the meeting addressed innovations in perioperative care of THA patients. Dr Barrack started the session with an interesting study examining the feasibility and patient preferences regarding telemedicine. A cross-sectional telephone survey of 163 arthroplasty patients indicated that 88% of patients use the internet and 94% own a device capable of videoconferencing. Nevertheless, only 18% of patients preferred a video visit over an in-person clinic visit due to concerns of inferior care. Dr Barnes quantified preoperative optimization work in 100 arthroplasty patients by using EMR activity logs and determined the surgical team spends an average 75 minutes per case on preoperative work activities. Dr Duwelius reported the early outcomes of primary THA with a smartphone-based exercise and educational platform compared to standard of care controls. A randomized control trial design with 365 patients demonstrated similar outcomes and non-inferiority of the smartphone platform relative to complications, readmissions, emergency room/urgent care visits. The association of controlled substance use with THA outcomes was assessed by Dr Higuera Rueda. A quantitative assessment using the NarxCare score identified 300 and above as a score associated with adverse outcomes after THA. Dr Macaulay reviewed data from a large retrospective study of 1,825 THAs indicating that discontinuation of intermittent pneumatic compression devices does not increase the risk of venous thromboembolism in standard risk patients being treated with 81mg ASA BID as prophylaxis. Dr Antoniou presented the final paper of the meeting investigating potential changes in patient health status as an indication for surgery over time. Data from this large systematic review of the literature found patients undergoing THA at similar health status to the past with no influence form patient age, gender, year of enrollment or geographic region. As summarized above, the 2020 virtual Hip Society Summer Meeting was rich in scientific content, productive discussion and a collaborative spirit. This collective body of work will result in impactful scientific contributions and will serve as a foundation for future innovation and advancements in the treatment of hip disease

Aims

Aseptic loosening is a leading cause of uncemented arthroplasty failure, often accompanied by fibrotic tissue at the bone-implant interface. A biological target, neutrophil extracellular traps (NETs), was investigated as a crucial connection between the innate immune system’s response to injury, fibrotic tissue development, and proper bone healing. Prevalence of NETs in peri-implant fibrotic tissue from aseptic loosening patients was assessed. A murine model of osseointegration failure was used to test the hypothesis that inhibition (through Pad4^-/- mice that display defects in peptidyl arginine deiminase 4 (PAD4), an essential protein required for NETs) or resolution (via DNase 1 treatment, an enzyme that degrades the cytotoxic DNA matrix) of NETs can prevent osseointegration failure and formation of peri-implant fibrotic tissue.

Aims

Some patients presenting with hip pain and instability and underlying acetabular dysplasia (AD) do not experience resolution of symptoms after surgical management. Hip-spine syndrome is a possible underlying cause. We hypothesized that there is a higher frequency of radiological spine anomalies in patients with AD. We also assessed the relationship between radiological severity of AD and frequency of spine anomalies.

Aims

Dual mobility (DM) implants have been shown to reduce the dislocation rate after total hip arthroplasty (THA), but there remain concerns about the use of cobalt chrome liners inserted into titanium shells. The aim of this study was to assess the clinical outcomes, metal ion levels, and periprosthetic femoral bone mineral density (BMD) at mid-term follow-up in young, active patients receiving a modular DM THA.

Aims

The aims of this study were to develop an in vivo model of periprosthetic joint infection (PJI) in cemented hip hemiarthroplasty, and to monitor infection and biofilm formation in real-time.