Alcohol and drug use in adults younger than 60 years with hip fracture - A comparison of validated instruments and the clinical eye: A prospective multicenter cohort study of 218 patients.

BACKGROUND: It is a common preconception that young individuals sustaining hip fractures have alcohol and/or drug use disorder. It is important to evaluate the actual use to avoid complications and plan the rehabilitation. AIM: The primary objective was to assess alcohol and drug consumption in hip fracture patients <60 years using the validated Alcohol Use Disorders Identification Test (AUDIT) and Drug Use Disorders Identification Test (DUDIT) scores. We secondarily investigated the agreement between the instruments and the physicians' clinical evaluation of usage. MATERIAL AND METHODS: This is a sub-study of 91 women and 127 men from a multicenter cohort study of patients with an acute hip fracture treated at four hospitals in Denmark and Sweden. AUDIT and DUDIT forms were completed by the patients. In addition, the researchers made an evaluation of the patients' alcohol/drug use based on direct patient contact and information on previous alcohol/drug use from medical charts. AUDIT ranges 0-40 with 6 (women) and 8 (men) as the cut-off for hazardous use. DUDIT ranges 0-44 with cut-offs of 2 and 6 indicating drug-related problems. RESULTS: According to the AUDIT, 29 % of the patients had a hazardous alcohol use (25 % women, 31 % men), whilst the clinical evaluation identified 26 % (24 % women, 28 % men). However, there was a low agreement between "the clinical eye" and AUDIT, as the clinical evaluation only correctly identified 35 of 56 individuals with AUDIT-scores indicating hazardous alcohol use. DUDIT equaled drug related problems in 8 % (5 % women, 10 % men), the clinical evaluation depicted 8 % with drug related problems (4 % women, 10 % men). The agreement was low between "the clinical eye" and DUDIT; only 7 of 15 with DUDIT-scores indicating drug related problems were correctly identified. CONCLUSION: Hazardous alcohol consumption is more common in non-elderly hip fracture patients than in the general population. Considering both self-reported alcohol use and clinical evaluation, women have almost as high rate as men. DUDIT indicated drug related problems to be slightly more common than in the population. Still, a majority did not exhibit troublesome use of neither alcohol nor drugs. The two screening methods do not identify the same individuals, and further investigation in clinical practice is needed.

Choice of Bearings Influences the Implant Survival of Total Hip Arthroplasty in Patients Who Have Osteoarthritis Aged 55 Years or More: Results of 158,044 Patients from the Nordic Arthroplasty Register Association from 2005 to 2017.

BACKGROUND: The aim of our study was to compare implant survival rates of different total hip arthroplasty (THA) bearings in the Nordic Arthroplasty Register Association. METHODS: All conventional primary THAs performed between 2005 and 2017 in patients over 55 years of age who had primary osteoarthritis were studied. Metal-on-highly crosslinked polyethylene (MoXLP), ceramic-on-highly crosslinked polyethylene (CoXLP), ceramic-on-ceramic (CoC), and metal-on-metal (MoM) bearings were included. The outcome was a revision. Kaplan-Meier (KM) estimates were calculated at 5 and 10 years. The risk for revision was analyzed using a flexible parametric survival model (FPSM) adjusted for nation, age, sex, femoral head size, and femoral fixation. RESULTS: A total of 158,044 THAs were included. The 5-year KM estimates were 95.9% (95% confidence interval [CI] 95.8 to 96.1) in MoXLP, 95.8% (95.6 to 96.1) in CoXLP, 96.7% (96.4 to 97.0) in CoC, and 93.9% (93.5 to 94.4) in MoM. The 10-year KM estimates were 94.2% (94.0 to 94.5) in MoXLP, 94.3% (93.9 to 94.8) in CoXLP, 95.4% (95.0 to 95.9) in CoC, and 85.5% (84.9 to 86.2) in MoM. Compared with MoXLP, the adjusted risk for revision was lower in CoC (hazard ratio [HR] 0.6, CI 0.5 to 0.6), similar in CoXLP (1.0, 0.9 to 1.0), and higher in MoM (1.3, 1.2 to 1.4). CONCLUSIONS: We found that MoXLP, CoXLP, and CoC bearings evinced comparably high implant survival rates up to 10 years, and they can all be regarded as safe options in this patient group. The MoM bearings were associated with clearly lower survivorship. The CoC bearings had the highest implant survival and a lower adjusted risk for revision compared with XLP bearings.

The "true" 1-year incidence of dislocation after primary total hip arthroplasty: validation of an algorithm identifying dislocations in the Danish National Patient Register based on 5,415 patients from the Danish Hip Arthroplasty Register.

BACKGROUND AND PURPOSE: Dislocations continue to be a serious complication after primary total hip arthroplasty (THA). Our primary aim was to report the "true" incidence of dislocations in Denmark and secondarily to validate a previously developed algorithm designed to identify THA dislocations in the updated version of the Danish National Patient Register (DNPR), based on data from the Danish Hip Arthroplasty Register (DHR). METHODS: We included 5,415 primary THAs from the DHR performed from July 1 to December 31, 2019. Version 3 of the DNPR was launched in February 2019, and a combination of data from the DNPR and a comprehensive national review of 1,762 hospital contacts enabled us to identify every dislocation occurring during the 1st year after THA to determine the "true" 1-year incidence of dislocation. The results were presented as proportions with 95% confidence intervals (CI), and validation was performed by calculating sensitivity and predictive values. RESULTS: The "true" 1-year incidence of dislocation was 2.8% (CI 2.4-3.3). Of these, 37% suffered recurrent dislocations during the follow-up period. Between-hospital variation ranged from 0.0% to 9.6%. The algorithm demonstrated a sensitivity close to 95%, while maintaining a positive predictive value of above 94%. CONCLUSION: The "true" 1-year incidence of dislocation of 2.8% is comparable to earlier findings, and large variation among hospitals continues to be evident. We have proven the algorithm to be valid in the latest DNPR (version 3), enabling it to be employed as a new quality indicator in future annual DHR reports.

Discontinuing the recommendation of hip precautions does not increase the risk of early dislocation after primary total hip arthroplasty using 36-mm heads: a population-based study from the Danish Hip Arthroplasty Register.

BACKGROUND AND PURPOSE: Dislocation is a severe complication following total hip arthroplasty (THA). Hip precautions have been recommended in the initial postoperative period but evidence supporting this practice is limited. We therefore conducted a population-based study to evaluate the association between discontinuing recommending postoperative hip precautions and the risk of early dislocation. METHODS: This is a cohort study with data from the Danish Hip Arthroplasty Register and the Danish National Patient Register. We included patients who underwent primary THA for osteoarthritis in 2004-2019 in public hospitals in the Capital Region of Denmark. The cohort was divided into the hip precautions group, comprising patients operated on between 2004 and 2009, and the no-precautions group operated on between 2014 and 2019. The primary outcome was the difference in the absolute risk of dislocation within 3 months post-surgery. The secondary outcome assessed the same risk within 2 years. We evaluated the difference in absolute risk using absolute risk regression (ARR). RESULTS: The cumulative incidence of dislocation within 3 months was 2.9% (confidence interval [CI] 2.5-3.3) in the hip precautions group and 3.5% (CI 3.1-3.9) in the no-precautions group. The risk of dislocation was higher in the no-precautions group but failed to reach statistical significance in the crude (ARR 1.2, CI 0.9-1.6) and multivariate model (ARR 1.4, CI 0.9-2.2). CONCLUSION: We found a higher but statistically insignificant increase in the risk of early dislocation in the no-precautions group. The lack of significance in the association may be explained by the increased use of 36-mm femoral heads after the guideline revision.

Prediction of Early Adverse Events After THA: A Comparison of Different Machine-Learning Strategies Based on 262,356 Observations From the Nordic Arthroplasty Register Association (NARA) Dataset.

OBJECTIVE: Preoperative risk prediction models can support shared decision-making before total hip arthroplasties (THAs). Here, we compare different machine-learning (ML) approaches to predict the six-month risk of adverse events following primary THA to obtain accurate yet simple-to-use risk prediction models. METHODS: We extracted data on primary THAs (N = 262,356) between 2010 and 2018 from the Nordic Arthroplasty Register Association dataset. We benchmarked a variety of ML algorithms in terms of the area under the receiver operating characteristic curve (AUROC) for predicting the risk of revision caused by periprosthetic joint infection (PJI), dislocation or periprosthetic fracture (PPF), and death. All models were internally validated against a randomly selected test cohort (one-third of the data) that was not used for training the models. RESULTS: The incidences of revisions because of PJI, dislocation, and PPF were 0.8%, 0.4%, and 0.3%, respectively, and the incidence of death was 1.2%. Overall, Lasso regression with stable iterative variable selection (SIVS) produced models using only four to five input variables but with AUROC comparable to more complex models using all 32 variables available. The SIVS-based Lasso models based on age, sex, preoperative diagnosis, bearing couple, fixation, and surgical approach predicted the risk of revisions caused by PJI, dislocations, and PPF, as well as death, with AUROCs of 0.61, 0.67, 0.76, and 0.86, respectively. CONCLUSION: Our study demonstrates that satisfactory predictive potential for adverse events following THA can be reached with parsimonious modeling strategies. The SIVS-based Lasso models may serve as simple-to-use tools for clinical risk assessment in the future.

Delirium diagnostic tools in the postoperative setting: A scoping review protocol.

BACKGROUND: Delirium is an acute and fluctuating disturbance in attention, awareness, and cognition, commonly observed in hospital settings, particularly among older adults, critically ill and surgical patients. Delirium poses significant challenges in patient care, leading to increased morbidity, mortality, prolonged hospital stays, and functional decline. AIM: The aim of this review is to map existing evidence on delirium diagnostic tools suitable for use in patients treated surgically due to hip fracture, to inform clinical practice and enhance patient care protocols in the postoperative setting. METHOD: We will conduct a scoping review on delirium diagnostic tools used for adult patients in the postoperative setting according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Eligibility criteria encompass all languages, publications dates, and study designs, with exception of case-reports. We will systematically search multiple databases and include unpublished trials, ensuring a comprehensive review based on a predefined protocol. RESULTS: Results will be presented descriptively, with supplementary tables and graphs. Studies will be grouped by design, surgical specialties, and diagnostic tools to identify potential variations. CONCLUSION: This scoping review will provide an overview of existing delirium diagnostic tools used in the postoperative setting and highlight knowledge-gaps to support future research. Due to the large number of patients affected by postoperative delirium, evidence mapping is much needed to facilitate evidence-based practice.

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

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

Implementation of outpatient hip and knee arthroplasty in a multicenter public healthcare setting.

BACKGROUND AND PURPOSE: Length of hospital stay after hip and knee arthroplasty is about 1 day in Denmark with few patients discharged on the day of surgery. Hence, a protocol for multicenter implementation of discharge on day of surgery has been instituted. We aimed to describe the implementation of outpatient hip and knee arthroplasty in a multicenter public healthcare setting. METHODS: We performed a prospective multicenter study from 7 public hospitals across Denmark. Patients were screened using well-defined in- and exclusion criteria and were discharged on day of surgery when fulfilling functional discharge criteria. The study period was from September 2022 to February 2023 with variable start of implementation. Data from the same centers in a 6-month period before the COVID pandemic from July 2019 to December 2019 was used for baseline control. RESULTS: Of 2,756 primary hip and knee arthroplasties, 37% (95% confidence interval [CI] 35-39) were eligible (range 21-50% in centers) and 52% (range 24-62%) of these were discharged on day of surgery. 21% (CI 20-23) of all patients (eligible and non-eligible) were discharged on day of surgery with a range of 10-31% within centers. This was an additional 15% (CI 13-17, P < 0.001) compared with patients discharged in the control period (6% in 2019). CONCLUSION: We found it possible to perform outpatient hip and knee replacement in 21% of patients in a public healthcare setting, probably to be increased with further center experience.

Total hip arthroplasty performed in summer is not associated with increased risk of revision due to prosthetic joint infection: a cohort study on 58 449 patients with osteoarthritis from the Danish Hip Arthroplasty Register.

Aims: Danish surveillance data indicated a higher risk of revision due to prosthetic joint infection (PJI) following total hip arthroplasty (THA) performed during the summer season. We investigated the association between summer and revision risk following primary THA. Methods: This study identified 58 449 patients from the Danish Hip Arthroplasty Register (DHR) with unilateral primary THA due to osteoarthritis from 2010-2018. From Danish Health Registries, we retrieved information on Charlson Comorbidity Index (CCI), immigration, and death and microbiological data on intraoperative biopsies and cohabitation status. Meteorological data were received from the Danish Meteorological Institute. Summer was defined as June-September, and THAs performed during October-May were used as controls. The primary outcome was revision due to PJI: the composite of revision with ≥2 culture-positive biopsies or reported PJI to the DHR. The secondary outcome was any revision. The cumulative incidences of revision and the corresponding adjusted relative risk (RR) with 95 % confidence intervals (CI) were calculated by season of the primary THA. Results: A total of 1507 patients were revised, and 536 were due to PJI. The cumulative incidence for THAs performed during summer and the rest of the year was 1.1 % (CI 1.0-1.3) and 1.1 % (CI 1.0-1.2) for PJI revision and 2.7 % (CI 2.5-3.0) and 2.5 % (CI 2.4-2.7) for any revision, respectively. The adjusted RR for THAs performed during summer vs. the rest of the year for PJI revision and any revision was 1.1 (CI 0.9-1.3) and 1.1 (CI 1.0-1.2), respectively. Conclusion: We found no association between summer and the risk of PJI revision or any revision in a northern European climate.

Sense of coherence as a predictor for patients' quality of recovery after total hip or knee arthroplasty - A descriptive cohort study.

BACKGROUND: Patients' postoperative quality of recovery (QOR) is an important outcome measurement and predicting and preventing impaired quality of recovery is essential. In this study, we aimed to investigate if patients Sense of Coherence (SOC) could be a potential predictor and screening instrument for impaired quality of recovery. We hypothesized that patients' SOC is positively related to their QOR. MATERIAL AND METHODS: The study was performed as a descriptive single-center prospective cohort study. Data was collected using digital questionnaires. Patients undergoing total hip (THA) or knee arthroplasty (TKA) received the SOC13 questionnaire prior to their surgery to establish their SOC and a questionnaire on postoperative day 2 and 7, respectively, establishing their QOR. Multiple linear regression was used to fit a model for the QOR score using SOC, age, sex, and type of surgery as potential explanatory variables. RESULTS: 206 patients were included in the study analysis. The results showed a highly significant positive correlation between patients' SOC and their postoperative QOR on both postoperative day 2 and 7 (p < 0.01). Patients with a lower SOC score also presented a significantly lower QOR score, meaning they experienced impaired QOR compared to patients with a higher SOC score. CONCLUSIONS: The results indicate that a weak SOC (low SOC score) can be considered a clinically important indicator for risk of impaired QOR (low QOR score) after THA and TKA. The SOC13 questionnaire may be a potential screening instrument identifying patients in risk of impaired postoperative QOR based on a low SOC score.

Protocol for a prospective multicentre cohort study to address the question whether diabetes and its management is still a risk factor in fast-track joint arthroplasty.

INTRODUCTION: Perioperative glycaemic control is important. However, the complexity of guidelines for perioperative diabetes management is complicated due to different and novel antihyperglycaemic medications, limited procedure-specific data and lack of data from implemented fast-track regimens which otherwise are known to reduce morbidity and glucose homeostasis disturbances. Consequently, outcome in patients with diabetes mellitus (DM) after surgery and the influence of perioperative diabetes management on postoperative recovery remains poorly understood. METHODS AND ANALYSIS: A prospective observational multicentre study involving 8 arthroplasty centres across Denmark with a documented implemented fast-track programme (median length of hospitalisation (LOS) 1 day). We will collect detailed perioperative data including preoperative haemoglobin A1c and antidiabetic treatment in 1400 unselected consecutive patients with DM undergoing hip and knee arthroplasty from September 2022 to December 2025, enrolled after consent. Follow-up duration is 90 days after surgery. The primary outcome is the proportion of patients with DM with LOS >4 days and 90-day readmission rate after fast-track total hip arthroplasty (THA), total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA). The secondary outcome is the association between perioperative diabetes treatment and LOS >2 days, 90-day readmission rate, other patient demographics and Comprehensive Complication Index for patients with DM after THA/TKA/UKA in a fast-track regimen. ETHICS AND DISSEMINATION: The study will follow the principles of the Declaration of Helsinki and ICH-Good Clinical Practice guideline. Ethical approval was not necessary as this is a non-interventional observational study on current practice. The trial is registered in the Region of Southern Denmark and on ClinicalTrials.gov. The main results and all substudies of this trial will be published in peer-reviewed international medical journals. TRIAL REGISTRATION NUMBER: NCT05613439.

Non-opioid analgesic combinations following total hip arthroplasty (RECIPE): a randomised, placebo-controlled, blinded, multicentre trial.

BACKGROUND: Multimodal postoperative analgesia following total hip arthroplasty is recommended, but the optimal combination of drugs remains uncertain. The aim of the RECIPE trial was to investigate the relative benefit and harm of the different combinations of paracetamol, ibuprofen, and the analgesic adjuvant dexamethasone for treatment of postoperative pain following total hip arthroplasty. METHODS: The RECIPE trial was a randomised, blinded, placebo-controlled trial conducted at nine Danish hospitals. Adults scheduled for total hip arthroplasty were randomly assigned (1:1:1:1) using a computer-generated list with stratification by site to receive combinations of oral paracetamol 1000 mg every 6 h, oral ibuprofen 400 mg every 6 h, or a single-dose of intravenous dexamethasone 24 mg in the following groups: paracetamol plus ibuprofen, ibuprofen plus dexamethasone, paracetamol plus dexamethasone, and paracetamol plus ibuprofen plus dexamethasone. The primary outcome was 24 h intravenous morphine consumption, analysed in a modified intention-to-treat population, defined as all randomly assigned participants who underwent total hip arthroplasty. The predefined minimal important difference was 8 mg. Safety outcomes included serious and non-serious adverse events within 90 days and 24 h. The trial was registered with ClinicalTrials.gov, NCT04123873. FINDINGS: Between March 5, 2020, and Nov 15, 2022, we randomly assigned 1060 participants, of whom 1043 (589 [56%] women and 454 [44%] men) were included in the modified intention-to-treat population. 261 were assigned to paracetamol plus ibuprofen, 262 to ibuprofen plus dexamethasone, 262 to paracetamol plus dexamethasone, and 258 to paracetamol plus ibuprofen plus dexamethasone. Median 24 h morphine consumption was 24 mg (IQR 12-38) in the paracetamol plus ibuprofen group, 20 mg (12-32) in the paracetamol plus dexamethasone group, 16 mg (10-30) in the ibuprofen plus dexamethasone group, and 15 mg (8-26) in the paracetamol plus ibuprofen plus dexamethasone group. The paracetamol plus ibuprofen plus dexamethasone group had a significantly reduced 24 h morphine consumption compared with paracetamol plus ibuprofen (Hodges-Lehmann median difference -6 mg [99% CI -10 to -3]; p<0·0001) and paracetamol plus dexamethasone (-4 mg [-8 to -1]; p=0·0013), however, none of the comparisons showed differences reaching the minimal important threshold of 8 mg. 91 (35%) of 258 participants in the paracetamol plus ibuprofen plus dexamethasone group had one or more adverse events, compared with 99 (38%) of 262 in the ibuprofen plus dexamethasone group, 103 (39%) of 262 in the paracetamol plus dexamethasone group, and 165 (63%) of 261 in the paracetamol plus ibuprofen group. INTERPRETATION: In adults undergoing total hip arthroplasty, a combination of paracetamol, ibuprofen, and dexamethasone had the lowest morphine consumption within 24 h following surgery and the most favourable adverse event profile, with a lower incidence of serious and non-serious adverse events (primarily driven by differences in nausea, vomiting, and dizziness) compared with paracetamol plus ibuprofen. FUNDING: The Novo Nordisk Foundation and Næstved-Slagelse-Ringsted Hospitals' Research Fund.

Return to work policies and practices after total hip or knee arthroplasty in Denmark, Germany, and the Netherlands: an exploratory study.

PURPOSE: To explore return-to-work (RTW) policies and practices for total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients in three European countries. MATERIALS AND METHODS: An exploratory study in Denmark, Germany, and the Netherlands consisting of three aspects: (1) description of the healthcare and social security systems; (2) identification of national RTW guidelines; (3) a survey to gain insight into RTW practices and perceptions of orthopaedic surgeons, including barriers, facilitators, and needs. RESULTS: Healthcare and social security systems differed (e.g. fast-track vs longer postoperative stay; coverage of rehabilitation costs). National guidelines were available in Germany (THA, TKA) and the Netherlands (TKA), containing limited RTW information. The survey was completed by 168 orthopaedic surgeons (Denmark n = 51; Germany n = 39; the Netherlands n = 78). Overall, orthopaedic surgeons reported being in need of more knowledge and better collaboration with other healthcare practitioners. CONCLUSION: We found considerable variation in healthcare and social security systems. When available, national guidelines contained limited information. In all three countries surgeons need more knowledge and better collaboration with other healthcare practitioners. We advise that RTW multidisciplinary recommendations post THA/TKA be established by the national associations of the healthcare practitioners involved.

Orthopaedic surgeons (regardless of country) need more knowledge, including "guidelines", "scientific evidence", and "expertise with work/return-to-work", to adequately support return to work.Orthopaedic surgeons need better collaboration with other healthcare practitioners to adequately support total hip arthroplasty or total knee arthroplasty patients to return to work.Multidisciplinary recommendations for returning to work after total hip arthroplasty or total knee arthroplasty should be established by the national associations of the healthcare practitioners involved.

Incidence of dislocation and associated risk factors in patients with a femoral neck fracture operated with an uncemented hemiarthroplasty.

BACKGROUND: Several factors might be associated with risk of dislocating following uncemented hemiarthroplasty (HA) due to femoral neck fracture (FNF). Current evidence is limited with great variance in reported incidence of dislocation (1-15%). Aim of this study was to identify the cumulative incidence of first-time dislocation following HA and to identify the associated risk factors. METHOD: We performed a retrospective cohort study of patients receiving an HA (BFX Biomet stem, posterior approach) at Copenhagen University Hospital, Bispebjerg, in 2010-2016. Patients were followed until death or end of study (dec 2018). Dislocation was identified by code extraction from the Danish National Patient Registry. Variables included in the multivariate model were defined pre-analysis to include: age, sex and variables with a p-value < 0.1 in univariate analysis. A regression model was fitted for 90 days dislocation as the assumption of proportional hazard rate (HR) was not met here after. RESULTS: We identified 772 stems (some patients occurred with both right and left hip) and 58 stems suffered 90 dislocations during the observation period, resulting in a 7% (CI 5-9) incidence of dislocation 90 days after index surgery. 55 of the 58 stems (95%) experienced the first dislocation within 90 days after surgery. Only absence of dementia was identified as an independent protective factor in the cause-specific model (HR 0.46 (CI 0.23-0.89)) resulting in a 2.4-fold cumulative risk of experiencing a dislocation in case of dementia. Several other variables such as age, sex, various medical conditions, surgery delay and surgical experience were eliminated as statistical risk factors. We found a decrease in survival probability for patients who experienced a dislocation during follow-up. CONCLUSIONS: The incidence of first-time dislocation of HA (BFX Biomet stem, posterior approach) in patients with a hip fracture is found to be 7% 90 days after surgery. Due to the non-existing attribution bias, we claim it to be the true incidence. Dementia was among several variables identified as the only risk factor for dislocation. In perspective, we may consider treating patients with dementia by other methods than HA e.g., HA with cement or with a more constrained solution. Also, a surgical approach that reduce the risk of dislocation should be considered.

Associations of dexamethasone's effect on morphine consumption after total knee arthroplasty-Subgroup analyses.

The DEXamethasone twice for pain treatment after Total Knee Arthroplasty (DEX-2-TKA) trial showed that adding one and two doses of 24 mg intravenous dexamethasone to paracetamol, ibuprofen and local infiltration analgesia, reduced morphine consumption (primary outcome) within 48 h after TKA. We aimed to explore the differences in the effect of dexamethasone on morphine consumption in different subgroups. Quantile regression adjusted for site was used to test for significant interaction between the predefined dichotomised subgroups and treatment group. The subgroups were defined based on baseline data: sex (male/female), age (≤65 years/>65 years), American Society of Anaesthesiologists (ASA)-score (ASA I + II/III), visual analogue score of preoperative pain at rest (≤30 mm/>30 mm), pain during mobilisation (≤30 mm/>30 mm), type of anaesthesia (spinal anaesthesia/general anaesthesia and spinal converted to general anaesthesia), and prior daily use of analgesics (either paracetamol and/or NSAID/neither). These analyses were supplemented with post hoc multivariate linear regression analyses. Test of interaction comparing sex in the pairwise comparison between DX2 (dexamethasone [24 mg] + dexamethasone [24 mg]) versus placebo (p = .02), showed a larger effect of dexamethasone on morphine consumption in male patients compared to females. Test of interaction comparing age in the pairwise comparison between DX1 (dexamethasone [24 mg] + placebo) versus placebo (p = .04), showed a larger effect of dexamethasone on morphine consumption in younger patients (≤65 years) compared to older. All remaining subgroup analyses showed no evidence of a difference. The supplemental multivariate analyses did not support any significant interaction for sex (p = .256) or age (p = .730) but supported a significant interaction with the type of anaesthesia (p < .001). Our results from the quantile regression analyses indicate that the male sex and younger age (≤65 years) may be associated with a larger analgesic effect of dexamethasone than the effects in other types of patients. However, this is not supported by post-hoc multivariate linear regression analyses. The two types of analyses both supported a possible interaction with the type of anaesthesia.

Are Outcomes From an Exercise Therapy and Patient Education Program for Osteoarthritis Associated With Hip and Knee Replacement Within Two Years? A Register-Based Study of 9,339 Patients With Osteoarthritis.

OBJECTIVE: The objective of this study was to determine whether short-term outcomes from exercise therapy and patient education for osteoarthritis (OA) are associated with hip or knee replacement within two years. METHODS: Individual-level data from the Good Life with osteoArthritis in Denmark (GLA:D) Registry were linked to the Danish National Patient Registry and other national registries. Cox proportional hazards models were used to investigate associations between program outcomes (baseline to three-month changes) and time to primary hip or knee replacement. Patients who did not receive joint replacement were censored at two years, time of death, or emigration. RESULTS: A total of 2,304 and 7,035 patients with clinically diagnosed hip and knee OA, respectively, were included. Of these, 30% with hip OA and 10% with knee OA had joint replacement within two years. Postprogram improvements in hip-related quality of life and arthritis self-efficacy (pain subscale) were associated with a reduced hazard of hip replacement (adjusted hazard ratios [HRs] for a 10-unit improvement: 0.74 [95% confidence interval (CI) 0.69-0.80] and 0.90 [95% CI 0.85-0.96], respectively). Improvements in knee pain, knee-related quality of life, and arthritis self-efficacy (pain subscale) were associated with a lower hazard of knee replacement (adjusted HRs for 10-unit improvement: 0.81 [95% CI 0.76-0.86] to 0.90 [95% CI 0.86-0.95], 0.70 [95% CI 0.63-0.78] to 0.79 [95% CI 0.72-0.86], and 0.89 [95% CI 0.83-0.94], respectively). CONCLUSION: The magnitude of improvement in key measures after exercise therapy and education was significantly associated with the likelihood of surgery. Progression to hip replacement was three times higher than progression to knee replacement. This information can guide patient-clinician conversations around anticipated program outcomes.

Prolonged effects of dexamethasone following total knee arthroplasty: A pre-planned sub-study of the DEX-2-TKA trial.

OBJECTIVES: The DEX-2-TKA trial demonstrated that one and two doses of 24 mg intravenous dexamethasone reduced opioid consumption and pain after total knee arthroplasty (TKA). We aimed to investigate the prolonged effects of dexamethasone after the 48-h intervention period. DESIGN: This was a prospective, pre-planned questionnaire follow-up on postoperative days 3-7 of patients in the DEX-2-TKA trial that randomly received: DX1 (dexamethasone 24 mg + placebo), DX2 (dexamethasone 24 mg + dexamethasone 24 mg), and placebo (placebo + placebo) perioperatively and 24 h later. SETTING: A multicenter trial performed at five Danish hospitals. PARTICIPANTS: We analyzed 434 of 485 adult participants enrolled in the DEX-2-TKA trial. OUTCOME MEASURES: Primary outcome was difference between groups in average of all numerical rating scale (NRS) pain scores reported in the morning, at bedtime, and the daily average pain on postoperative days 3-7. Secondary outcomes were sleep quality and patient satisfaction. RESULTS: The median (interquartile range) pain intensity levels for postoperative days 3-7 were: DX2 3.2 (2.1-4.3); DX1 3.3 (2.3-4.1); and placebo 3.3 (2.5-4.7). Hodges-Lehmann median differences between groups were: 0 (95% confidence interval - 0.54 to 0.2), P = 0.38 between DX1 and placebo; 0.1 (-0.47 to 0.33), p = .87 between DX1 and DX2; and 0.1 (-0.6 to 0.13), p = .20 between DX2 and placebo. We found no relevant differences between groups on sleep quality on postoperative days 3-7 nor for patient satisfaction with the analgesic treatment. CONCLUSIONS: We found that neither one nor two doses of 24 mg intravenous dexamethasone demonstrated prolonged effects on overall pain or sleep quality on postoperative days 3-7 after total knee arthroplasty. We also found that dexamethasone had no effect on patient satisfaction. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov NCT03506789 (main result trial).

No Association Between Previous General Infection and Prosthetic Joint Infection After Total Hip Arthroplasty-A National Register-Based Cohort Study on 58,449 Patients Who Have Osteoarthritis.

BACKGROUND: Prosthetic joint infection (PJI) following total hip arthroplasty (THA) is a complication associated with increased risk of death. There is limited knowledge about the association between infection before THA, and risk of revision due to PJI. We investigated the association between any previous hospital-diagnosed or community-treated infection 0 to 6 months before primary THA and the risk of revision. METHODS: We obtained data on 58,449 patients who were operated with primary unilateral THA between 2010 and 2018 from the Danish Hip Arthroplasty Register. Information on previous infection diagnoses, redeemed antibiotic prescriptions up to 1 year before primary THA, intraoperative biopsies, and cohabitations was retrieved from Danish health registers. All patients had a 1-year follow-up. Primary outcome was revision due to PJI. Secondary outcome was any revision. We calculated the adjusted relative risk with 95% confidence intervals (CI), treating death as competing risk. RESULTS: Among 1,507 revisions identified, 536 were due to PJI with a cumulative incidence of 1.0% ([CI] 0.9 to 1.2) and 0.9% ([CI] 0.8 to 1.0) for patients who did and did not have previous infection. For any revision, the cumulative incidence was 3.1% ([CI] 2.9 to 3.4) and 2.4% ([CI] 2.3 to 2.6) for patients who did and did not have previous infection. The adjusted relative risk for PJI revision was 1.1 ([CI] 0.9 to 1.4) and for any revision 1.3 ([CI] 1.1 to 1.4) for patients who did have previous infection compared to those who did not. CONCLUSION: Previous hospital-diagnosed or community-treated infection 0 to 6 months before primary THA does not increase the risk of PJI revision. It may be associated with increased risk of any revision.

Machine-learning vs. logistic regression for preoperative prediction of medical morbidity after fast-track hip and knee arthroplasty-a comparative study.

BACKGROUND: Machine-learning models may improve prediction of length of stay (LOS) and morbidity after surgery. However, few studies include fast-track programs, and most rely on administrative coding with limited follow-up and information on perioperative care. This study investigates potential benefits of a machine-learning model for prediction of postoperative morbidity in fast-track total hip (THA) and knee arthroplasty (TKA). METHODS: Cohort study in consecutive unselected primary THA/TKA between 2014-2017 from seven Danish centers with established fast-track protocols. Preoperative comorbidity and prescribed medication were recorded prospectively and information on length of stay and readmissions was obtained through the Danish National Patient Registry and medical records. We used a machine-learning model (Boosted Decision Trees) based on boosted decision trees with 33 preoperative variables for predicting "medical" morbidity leading to LOS > 4 days or 90-days readmissions and compared to a logistical regression model based on the same variables. We also evaluated two parsimonious models, using the ten most important variables in the full machine-learning and logistic regression models. Data collected between 2014-2016 (n:18,013) was used for model training and data from 2017 (n:3913) was used for testing. Model performances were analyzed using precision, area under receiver operating (AUROC) and precision recall curves (AUPRC), as well as the Mathews Correlation Coefficient. Variable importance was analyzed using Shapley Additive Explanations values. RESULTS: Using a threshold of 20% "risk-patients" (n:782), precision, AUROC and AUPRC were 13.6%, 76.3% and 15.5% vs. 12.4%, 74.7% and 15.6% for the machine-learning and logistic regression model, respectively. The parsimonious machine-learning model performed better than the full logistic regression model. Of the top ten variables, eight were shared between the machine-learning and logistic regression models, but with a considerable age-related variation in importance of specific types of medication. CONCLUSION: A machine-learning model using preoperative characteristics and prescriptions slightly improved identification of patients in high-risk of "medical" complications after fast-track THA and TKA compared to a logistic regression model. Such algorithms could help find a manageable population of patients who may benefit most from intensified perioperative care.