The SPAIRE technique (Saving Piriformis And Internus, Repair Externus) was first described in 2016 and an approach to the hip in the interval between the inferior gemellus and quadratus femoris can be used for both hemi- and total hip arthroplasty. The HemiSPAIRE technique in hip hemiarthroplasty for displaced intracapsular fractures has been compared with the standard lateral approach (advocated by NICE) in a pragmatic, superiority, multicentre, randomised controlled trial into postoperative mobility and function. This NIHR funded study was recruited between November 2019 and April 2022 and the results are reported in this presentation. The author has used the SPAIRE technique in 1026 routine primary total hip replacements since February 2016. The technique is described along with results from NJR data. SPAIRE is most challenging in patients with small anatomy, reduced offset, with an external rotation deformity. Particularly in these, but in all cases, MAKO robotic assistance facilitates accurate implantation of prostheses and precise recreation of biomechanics. The MAKO robot has been used in all cases since 2018 and SPAIRE/MAKO is now the standard of care in the author's practice. To evaluate whether robotic-assisted tendon-sparing posterior approaches (piriformis sparing and SPAIRE), improve patient outcomes in total hip arthroplasty compared with a robotic-assisted standard posterior approach, the NIHR Efficacy and Mechanism Evaluation Programme has recently funded the HIPSTER trial (HIP Surgical Techniques to Enhance Rehabilitation). This is a single-centre, double-blinded, parallel three-arm, randomised, controlled, superiority trial; recruitment is in progress. The greatest value of robotic assistance may be when it is used in combination with tendon-sparing surgery. Data is being gathered to evaluate whether the SPAIRE/MAKO technique confers benefits with regard the speed of post-op mobilisation as well as accelerated return to unrestricted function

Total hip arthroplasty (THA) is one of the most successful surgical procedures of modern times, however debate continues as to the optimal orientation of the acetabular component and how to reliably achieve this. We hypothesised that functional CT-based planning with patient specific instruments using the Corin Optimised Positioning System (OPS) would provide more accurate component alignment than the conventional freehand technique using 2D templating.

A pragmatic single-centre, patient-assessor blinded, randomised control trial of patients undergoing THA was performed. 54 patients (age 18–70) were recruited to either OPS THA or conventional THA. All patients received a cementless acetabular component. Patients in both arms underwent pre- and post-operative CT scans, and four functional x-rays (standing and seated). Patients in the OPS group had a 3D surgical plan and bespoke guides made. Patients in the conventional group had a surgical plan based on 2D templating x-rays, and the pre-operative target acetabular orientation was recorded by the surgeon. The primary outcome measure was the difference between planned and achieved acetabular anteversion and was determined by post-operative CT scan performed at 6 weeks. Secondary outcome measures included Hip disability and Osteoarthritis Outcome Score (HOOS), Oxford Hip Score (OHS), EQ-5D and adverse events.

In the OPS group, the achieved acetabular anteversion was within 10° of the plan in 96% of cases, compared with only 76% of cases in the conventional group. For acetabular inclination, the achieved position in the OPS group was within 10° of the plan in 96% of cases, compared with in only 84% of cases in the conventional group. These differences were not statistically significant. The clinical outcomes were comparable between the two groups.

Large errors in acetabular orientation appear to be reduced when functional CT-based planning and patient-specific instruments are used compared to the freehand technique, but no statistically significant differences were seen in the difference between planned and achieved angles. Larger studies are needed to analyse this in more detail and to determine whether the reduced numbers of outliers lead to improved clinical outcomes.

Mixed Reality has the potential to improve accuracy and reduce required dissection for the performance of peri-acetabular osteotomy. The current work assesses initial proof of concept of MR guidance for PAO. A PAO planning module, based on preoperative computed tomography (CT) imaging, allows for the planning of PAO cut planes and repositioning of the acetabular fragment. 3D files (holograms) of the cut planes and native and planned acetabulum positions are exported with the associated spatial information. The files are then displayed on mixed reality head mounted device (HoloLens2, Microsoft) following intraoperative registration using an FDA-cleared mixed reality application designed primary for hip arthroplasty (HipInsight). PAO was performed on both sides of a bone model (Pacific Research). The osteotomies and acetabular reposition were performed in accordance with the displayed holograms. Post-op CT imaging was performed for analysis. Cutting plane-accuracy was evaluated using a best-fit plane and 2D angles (°) between the planned and achieved supra (SA)- and retroacetabular (RA) osteotomy and retroacetabular and ischial osteotomies (IO) were measured. To evaluate the accuracy of acetabular reorientation, we digitized the acetabular rim and calculated the acetabular opening plane. Absolute errors of planned and achieved operative inclination and anteversion (°) of the acetabular fragment, as well as 3D lateral-center-edge (LCE) angles were calculated. The mean absolute difference between the planned and performed osteotomy angles was 3 ± 3°. The mean absolute error between planned and achieved operative anteversion and inclination was 1 ± 0° and 0 ± 0° respectively. Mean absolute error between planned and achieved 3D LCE angle was 0.5 ± 0.7°. Mixed-reality guidance for the performance of pelvic osteotomies and acetabular fragment reorientation was feasible and highly accurate. This solution may improve the current standard of care by enabling reliable and precise reproduction of the desired acetabular realignment

Aims. The aim of the HIPGEN consortium is to develop the first cell therapy product for hip fracture patients using PLacental-eXpanded (PLX-PAD) stromal cells. Methods. HIPGEN is a multicentre, multinational, randomized, double-blind, placebo-controlled trial. A total of 240 patients aged 60 to 90 years with low-energy femoral neck fractures (FNF) will be allocated to two arms and receive an intramuscular injection of either 150 × 10. 6. PLX-PAD cells or placebo into the medial gluteal muscle after direct lateral implantation of total or hemi hip arthroplasty. Patients will be followed for two years. The primary endpoint is the Short Physical Performance Battery (SPPB) at week 26. Secondary and exploratory endpoints include morphological parameters (lean body mass), functional parameters (abduction and handgrip strength, symmetry in gait, weightbearing), all-cause mortality rate and patient-reported outcome measures (Lower Limb Measure, EuroQol five-dimension questionnaire). Immunological biomarker and in vitro studies will be performed to analyze the PLX-PAD mechanism of action. A sample size of 240 subjects was calculated providing 88% power for the detection of a 1 SPPB point treatment effect for a two-sided test with an α level of 5%. Conclusion. The HIPGEN study assesses the efficacy, safety, and tolerability of intramuscular PLX-PAD administration for the treatment of muscle injury following arthroplasty for hip fracture. It is the first phase III study to investigate the effect of an allogeneic cell therapy on improved mobilization after hip fracture, an aspect which is in sore need of addressing for the improvement in standard of care treatment for patients with FNF. Cite this article: Bone Jt Open 2022;3(4):340–347

Background. The purpose of this study is to evaluate the early outcomes with the use of a smartphone-based exercise and educational platform after primary total hip arthroplasty compared to a standard of care control group. Methods. A multicenter prospective randomized control trial was conducted evaluating the use of the mymobility smartphone-based care platform for primary total hip arthroplasty (THA). Patients randomized to the control group (198 patients) received the respective institution's standard of care. Those randomized to mymobility treatment group (167 patients) were provided an Apple Watch and mymobility smartphone application. The application provides pre and postoperative educational content, video directed exercise programs as well as tracks the patient's activity. Patients in the treatment group were not initially prescribed physical therapy, but could be if their surgeon deemed it necessary. Early outcomes assessed included 90-day hip range of motion, HOOS JR scores, 30-day single leg stance (SLS) and time up and go (TUG) test. We also evaluated PT utilization, THA complications associated with readmissions, ER visits not associated with readmissions, urgent care (non standard of care) visits, and physician office visits. Outcome scores include HOOS-Jr, EQ-5D-5L, single stance (SLS), Timed up and go (TUG). Satisfaction scores for the procedure and the mymobility study group were also recorded. Results. The control group was significantly younger by 3.0 years (p=0.007), but no significant difference between groups in BMI, gender or preoperative diagnosis. Postoperative PT utilization was statistically lower in the mymobility group. (P=.001). There were no statistically significant differences in complications, readmissions, or office visits. The 90-day outcomes showed no significant differences in hip flexion between controls (101.3±10.9) and mymobility (99.8 ±12) (p=0.34). HOOS JR scores were not significantly different between control group (84 ±14.5) and mymobility group (81 ±13) (p=0.15). Mean 30-day SLS time was 22.5 ±20 sec in the control group and 19.8 ±19 sec in the mymobility group (p=0.25). Mean TUG time was 14.1 ±27.4 sec for control group and 16.1 ±43.3 sec for my mobility group (p=0.7). Conclusion. The use of the mymobility care platform demonstrated similar early outcomes to traditional care models. This study showed a significant decrease in PTA utilization. Initial findings demonstrated non inferiority of the mymobility platform with regards to complications, readmissions, emergency room and urgent care visits. Strengths of this study include randomized, multicentered study design. Both groups were balanced except for age. Weakness of this study is the lack of preoperative functional testing which may influence postoperative single stance. This technology allows patients to rehabilitate on a more flexible schedule, avoid unnecessary healthcare visits as well as potentially decrease overall healthcare costs

Aims. The purpose of this study is to evaluate early outcomes with the use of a smartphone-based exercise and educational care management system after total hip arthroplasty (THA) and demonstrate decreased use of in-person physiotherapy (PT). Methods. A multicentre, prospective randomized controlled trial was conducted to evaluate a smartphone-based care platform for primary THA. Patients randomized to the control group (198) received the institution’s standard of care. Those randomized to the treatment group (167) were provided with a smartwatch and smartphone application. PT use, THA complications, readmissions, emergency department/urgent care visits, and physician office visits were evaluated. Outcome scores include the Hip disability and Osteoarthritis Outcome Score (HOOS, JR), health-related quality-of-life EuroQol five-dimension five-level score (EQ-5D-5L), single leg stance (SLS) test, and the Timed Up and Go (TUG) test. Results. The control group was significantly younger by a mean 3.0 years (SD 9.8 for control, 10.4 for treatment group; p = 0.007), but there were no significant differences between groups in BMI, sex, or preoperative diagnosis. Postoperative PT use was significantly lower in the treatment group (34%) than in the control group (55.4%; p = 0.001). There were no statistically significant differences in complications, readmissions, or outpatient visits. The 90-day outcomes showed no significant differences in mean hip flexion between controls (101° (SD 10.8)) and treatment (100° (SD 11.3); p = 0.507) groups. The HOOS, JR scores were not significantly different between control group (73 points (SD 13.8)) and treatment group (73.6 points (SD 13); p = 0.660). Mean 30-day SLS time was 22.9 seconds (SD 19.8) in the control group and 20.7 seconds (SD 19.5) in the treatment group (p = 0.342). Mean TUG time was 11.8 seconds (SD 5.1) for the control group and 11.9 (SD 5) seconds for the treatment group (p = 0.859). Conclusion. The use of the smartphone care management system demonstrated similar early outcomes to those achieved using traditional care models, along with a significant decrease in PT use. Noninferiority was demonstrated with regard to complications, readmissions, and ED and urgent care visits. This technology allows patients to rehabilitate on a more flexible schedule and avoid unnecessary healthcare visits, as well as potentially reducing overall healthcare costs. Cite this article: Bone Joint J 2021;103-B(7 Supple B):91–97

Introduction. Two-stage reimplantation for prosthetic joint infection (PJI) of the hip is the standard of care with a 5–10% recurrence at a minimum two-year follow-up. Compiling outcomes data for this standard of care is necessary in order to characterize long-term reinfection risk and the culpable microbiology. The purpose of this study was to determine the long-term success of two-stage reimplantation and identify the factors that affected the success. Methods. We performed a systematic review of randomized control trials, cohort studies, and case series through May 2019, searching Embase, Medline via PubMed, and Cochrane Library for the concept of two-stage reimplantation for the treatment of hip and knee PJIs, yielding 464 unique citations for abstract review, of which 135 were reviewed in full. Our parameters of interest included: reinfection and mortality events following successful reimplantation, the timing of these events, and the microbiology of index and recurrent infections. Results. Meeting our criteria were 59 studies with 4,494 patients (1,842 hips) who had completed reimplantation. Among successfully reimplanted hips, 4.76% (95% CI, 2.00–8.41) were reinfected by 24 months, 6.84% (4.92–9.02) were reinfected by final follow-up, 1.6% (0.32–3.52) were reinfected with an identical organism(s) with identical resistance, and 2.55% (0.77–5.03) were reinfected with a novel organism(s) or novel resistance. In 24 studies with reinfected patients and sufficient data, 8 studies reported an average interval from reimplantation to reinfection greater than 24 months, and 14 reported at least 1 patient with a reinfection event greater than 48 months following reimplantation. Conclusion. The results from this review determined that the host of an index PJI faces ongoing risk of recurrent infection years into the post-operative period despite initial eradication and that novel microbiology is the cause of a significant proportion of failures. For any tables or figures, please contact the authors directly

Aims. Delirium is associated with adverse outcomes following hip fracture, but the prevalence and significance of delirium for the prognosis and ongoing rehabilitation needs of patients admitted from home is less well studied. Here, we analyzed relationships between delirium in patients admitted from home with 1) mortality; 2) total length of hospital stay; 3) need for post-acute inpatient rehabilitation; and 4) hospital readmission within 180 days. Methods. This observational study used routine clinical data in a consecutive sample of hip fracture patients aged ≥ 50 years admitted to a single large trauma centre during the COVID-19 pandemic between 1 March 2020 and 30 November 2021. Delirium was prospectively assessed as part of routine care by the 4 A’s Test (4AT), with most assessments performed in the emergency department. Associations were determined using logistic regression adjusted for age, sex, Scottish Index of Multiple Deprivation quintile, COVID-19 infection within 30 days, and American Society of Anesthesiologists grade. Results. A total of 1,821 patients were admitted, with 1,383 (mean age 79.5 years; 72.1% female) directly from home. Overall, 87 patients (4.8%) were excluded due to missing 4AT scores. Delirium prevalence in the whole cohort was 26.5% (460/1,734): 14.1% (189/1,340) in the subgroup of patients admitted from home, and 68.8% (271/394) in the remaining patients (comprising care home residents and inpatients when fracture occurred). In patients admitted from home, delirium was associated with a 20-day longer total length of stay (p < 0.001). In multivariable analyses, delirium was associated with higher mortality at 180 days (odds ratio (OR) 1.69 (95% confidence interval (CI) 1.13 to 2.54); p = 0.013), requirement for post-acute inpatient rehabilitation (OR 2.80 (95% CI 1.97 to 3.96); p < 0.001), and readmission to hospital within 180 days (OR 1.79 (95% CI 1.02 to 3.15); p = 0.041). Conclusion. Delirium affects one in seven patients with a hip fracture admitted directly from home, and is associated with adverse outcomes in these patients. Delirium assessment and effective management should be a mandatory part of standard hip fracture care. Cite this article: Bone Jt Open 2023;4(6):447–456

Due to limitations of existing pharmacological therapies for the management of chronic pain in osteoarthritis (OA), surgical interventions remain a major component of current standard of care, with total joint replacements (TJRs) considered for people who have not responded adequately to conservative treatment. This study aimed to quantify the economic burden of moderate-to-severe chronic pain in patients with OA in England prior to TJR. A retrospective, longitudinal cohort design was employed using Clinical Practice Research Datalink GOLD primary care data linked to Hospital Episode Statistics secondary care data in England. Patients (age ≥18 years) with an existing OA diagnosis of any anatomical site (Read/ICD-10) were indexed (Dec-2009 to Nov-2017) on a moderate-to-severe pain event (which included TJR) occurring within an episode of chronic pain. 5-year TJR rates from indexing were assessed via Kaplan-Meier estimates. All-cause healthcare resource utilisation and direct medical costs were evaluated in the 1–12 and 13–24 months prior to the first TJR experienced after index. Statistical significance was assessed via paired t-tests. The study cohort comprised 5,931 eligible patients (57.9% aged ≥65 years, 59.2% female). 2,176 (36.7%) underwent TJR (knee: 54.4%; hip: 42.8%; other: 2.8%). The 5-year TJR rate was 45.4% (knee: 24.3%; hip: 17.5%; other: 6.8%). Patients experienced more general practitioner consultations in 1–12 months pre-TJR compared with 13–24 months pre-TJR (means: 12.13 vs. 9.61; p<0.0001), more outpatient visits (6.68 vs. 3.77; p<0.0001), more hospitalisations (0.74 vs. 0.62; p=0.0032), and more emergency department visits (0.29 vs. 0.25, p=0.0190). Total time (days) spent as an inpatient was higher in 1–12 months pre-TJR (1.86 vs. 1.07; p<0.0001). Mean total per-patient cost pre-TJR increased from £1,771 (13–24 months) to £2,621 (1–12 months) (p<0.0001). Resource-use and costs incurred were substantially greater in the 12 months immediately prior to TJR, compared with 13–24 months prior. Reasons for increased healthcare and economic burden in the pre-TJR period deserve further exploration as potential targets for efforts to improve patient experience and efficiency of care

Background. Much effort has been aimed at strategies for patient optimization, perioperative standards of care, and postoperative risk stratification to reduce the incidence of SSI. Examples include, newer dressing modalities, antibiotic-impregnated bone cement, intra-wound powdered antibiotics, as well as novel suture types and techniques, all of which have shown great potential. However, the question remains as to whether these changes in practice have led to lower overall infections over the past few years. Therefore, the purpose of this study was to track the annual rates and trends of: 1) overall; 2) deep; and 3) superficial SSI following total hip arthroplasty (THA) using the most recent data (2012 to 2016) from a large nationwide database. Methods. The National Surgical Quality Improvement Program database was queried for all primary THAs (CPT code 27130) between 2012 and 2016, yielding 122,451 cases. Cases with reported superficial and/or deep SSIs were combined for an overall rate, and then independently analyzed as deep and superficial SSIs. The infection incidence for each year was calculated. After an overall 5-year correlation and trends, univariate analysis was also performed to compare the most recent year, 2016, with each of the preceding 4 years. Furthermore, a comparison of overall and deep SSI incidences from this study were compared to meta-analysis of pooled data from 2001 to 2011. Pearson correlation coefficients and chi-squared tests were used to determine correlation and statistical significance which was maintained at a p-value less than 0.05. Results. Over the 5-year period, 1,154 cases out of 122,451 (0.94% of all cases) were complicated by any SSI. The lowest incidence was in the latest year, 2016 (n=289, 0.81%), while the greatest was in the earliest year, 2012 (n=163, 1.12%). There was a significant inverse correlation between overall SSI rate and year (p<0.01). A 31% decrease in rate was found between 2016 and 2012 (0.81% vs. 1.12%, p<0.01). For deep SSI, the lowest incidence was in the most recent year, 2016 (n=82, 0.23%). The incidence over 5 years was 0.30% (364 out of 122,451 cases). The mean percent decrease in deep SSI incidence over the 5 years was 31%. There was a 49% decrease in deep SSI rate in 2016 compared to 2015 (0.23% vs. 0.38%, p>0.05). Additionally, there was an inverse correlation between deep SSI rate and year of surgery (p>0.05). The lowest superficial SSI incidence occurred in the most recent year, 2016 (n=204, 0.58%), while 2012 had the greatest incidence (n=121, 0.83%). There were a total of 796 cases out of 122,451 over 5 years, an incidence of 0.65%. A 31% decrease was observed between 2016 and 2012 (0.58% vs. 0.83%, p=0.001). There was a statistically significant inverse correlation between superficial SSI rate and year (p<0.01). A meta-analysis evaluating primary THA SSIs from 2001 to 2011 reported an overall SSI incidence of 2.5% (95% confidence interval [Cl], 1.4%-4.4%; P<.001; n=28,883), substantially higher (309%) than the 2016 incidence of 0.81% found in this study. Furthermore, the meta-analysis reported an incidence for deep SSIs to be 0.9% (95% Cl, 0.4%-2.2%; p<.001; n=28,883), also found to be markedly lower than the 2016 incidence noted here (0.23%), marking a 391% difference. Conclusion. The findings from this study suggest that the evolving standards of care have brought about improvements in SSI prevention following THA over time. Deep SSIs, which can pose substantial threats to implant survivorship, have decreased throughout the years. These results highlight the importance of following up-to-date clinical recommendations to reduce surgical site infections and substantially improve patient outcomes

Introduction. Interferon (IFN) based treatments for chronic hepatitis C (HCV) have been the standard of care until 2014 when direct antiviral agents (DAA) were introduced. Patients with HCV have had extremely high complication rates after total hip arthroplasty (THA). It is unknown whether HCV is a modifiable risk factor for these complications prior to THA. The purpose of this study was 1) to compare perioperative complication rates between untreated and treated HCV in THA and 2) to compare these rates between patients treated with two different therapies (IFN vs. DAA). Methods. A multicenter retrospective database query was used to identify patients diagnosed with chronic hepatitis C virus who underwent total hip arthroplasty from 2006–2016. All patients (n=105) identified were included and were divided into two groups: untreated HCV (n=63) and treated (n=42); the treated group were further subdivided into those receiving IFN based therapies (n=16) or DAA therapies (n=26). Comparisons between the treated and untreated groups were made with respect to demographic data, comorbidities, preoperative viral load, MELD score, and all surgical (≤1 yr) and medical (≤90d) complications; a sub-group analysis of the treated patients was also performed. Separate independent t-tests were conducted for dependent variables that were normally distributed, and Mann-Whitney U tests were conducted for variables which were not normally distributed. Categorical variables were compared through the chi-square test of independence. The level of statistical significance was set at p<0.05. Results. Of the 105 patients, there was a greater number of HIV infected patients in the untreated group and a higher number of smokers in the treated group. Surgical complication rates were higher in the untreated group (25.4% vs. 4.8%; p<0.05) with a PJI rate of 14.3% in the untreated group. There were no differences in medical complications. A sub-group analysis of the different treatments for HCV did not reveal any differences in post-surgical complications. Discussion and Conclusion. Untreated HCV is traditionally associated with an extremely high rate of postoperative complications following THA. Treatment for HCV prior to THA appears to be associated fewer postoperative complications, primarily PJI. While further investigation is warranted, strong consideration should be given to treating patients for HCV prior to elective THA

Aims

The Birmingham Hip Resurfacing (BHR) arthroplasty has been used as a surgical treatment of coxarthrosis since 1997. We present 20-year results of 234 consecutive BHRs performed in our unit.

Aims

The aims of this study were to determine if an increasing serum cobalt (Co) and/or chromium (Cr) concentration is correlated with a decreasing Harris Hip Score (HHS) and Hip disability and Osteoarthritis Outcome Score (HOOS) in patients who received the Articular Surface Replacement (ASR) hip resurfacing arthroplasty (HRA), and to evaluate the ten-year revision rate and show if sex, inclination angle, and Co level influenced the revision rate.

Aims

The primary aim of this study is to compare mobility status of patients receiving oral oxycodone with those receiving subcutaneous alfentanil as analgesic methods prior to mobilization to help physiotherapy compliance after hip fracture surgery. The secondary aims are to assess postoperative pain, health-related quality of life, in-hospital length of stay, total use of analgesia over postoperative days 1 and 2 (POD 1 and POD 2), complication rates within 30 days, and 30-day mortality rates.

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

The Forgotten Joint Score-12 (FJS-12) is a validated patient-reported outcome measure (PROM) tool designed to assess artificial prosthesis awareness during daily activities following total hip arthroplasty (THA). The patient-acceptable symptom state (PASS) is the minimum cut-off value that corresponds to a patient’s satisfactory state-of-health. Despite the validity and reliability of the FJS-12 having been previously demonstrated, the PASS has yet to be clearly defined. This study aims to define the PASS of the FJS-12 following primary THA.

In Africa the amount of joint replacement surgery is increasing, but the indications for operation and the age of the patients are considerably different from those in the developed world. New centres with variable standards of care and training of the surgeons are performing these procedures and it is important that a proper audit of this work is undertaken. In Malawi, we have pioneered a Registry which includes all joint replacements that have been carried out in the country. The data gathered include the age, gender, indication for operation, the prosthesis used, the surgical approach, the use of bone graft, the type of cement, pressurising systems and the thromboprophylaxis used. All patients have their clinical scores recorded pre-operatively and then after three and six months and at one year. Before operation all patients are counselled and on consent their HIV status is established allowing analysis of the effect of HIV on successful joint replacement. To date, 73 total hip replacements (THRs) have been carried out in 58 patients by four surgeons in four different hospitals. The most common indications for THR were avascular necrosis (35 hips) and osteoarthritis (22 hips). The information concerning 20 total knee replacements has also been added to the Registry

Aims

This study aims to assess the feasibility of conducting a pragmatic, multicentre randomized controlled trial (RCT) to test the clinical and cost-effectiveness of an informal caregiver training programme to support the recovery of people following hip fracture surgery.

Aims

Bone marrow-derived mesenchymal stem cells obtained from bone marrow aspirate concentrate (BMAC) with platelet-rich plasma (PRP), has been used as an adjuvant to hip decompression. Early results have shown promise for hip preservation in patients with osteonecrosis (ON) of the femoral head. The purpose of the current study is to examine the mid-term outcome of this treatment in patients with precollapse corticosteroid-induced ON of the femoral head.

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.