The Swedish Hip Arthroplasty Register

BackgroundHip abductor mechanism deficiency due to abductor tendon degeneration, tear, or intraoperative damage during total hip arthroplasty (THA) may cause severe walking disability. For severe abductor weakness in native hip joints, Whiteside muscle transfer is a good solution. However, the literature on the results of abductor mechanism reconstruction (AMR) after THA remains limited. Our study aimed to assess the outcome of AMR in patients with THA suffering from Milwaukee III and IV hip abductor deficiency.MethodsWe conducted a single-center retrospective cohort study of THA with hip abductor mechanism deficiency treated surgically with AMR. Data were collected between January 2011 and December 2019 and included the following parameters: patient’s data, subjective level of pain, Harris Hip Score (HHS), gait pattern, extent of hip abductor tear, and offset measurements.ResultsThe cohort included 16 THAs with AMR in 16 patients. The whole group median HHS improved from 37.1 interquartile range (IQR) (31.0-38.7) to 73.9 IQR (63.5-83.7) (P < .001). In a subgroup of 9 hips, the global offset was preserved after THA while it was reduced in remaining 7 hips. All patients with preserved global offset had significantly better clinical outcome compared to the group with reduced global offset (median HHS improvement was 48 IQR [46-53] compared to 22 IQR [18-25], P = .001).ConclusionsOur study showed favorable outcome of the AMR for chronic, Milwaukee III and IV hip abductor deficiency after THA. It is the first study to show that restoration of global offset after THA is of utmost importance to avoid chronic abductor mechanism deficiency.

Background:The use of antibiotic-loaded bone cement (ALBC) in primary total knee arthroplasty (TKA) is debated. Some argue that ALBC might only be justified in high-risk patients. This study assessed the effectiveness of ALBC vs. plain bone cement (PBC) in reducing risk of revision for periprosthetic joint infection (PJI) in TKA patients considered to have a high risk of infection.Methods:Cohort study of primary TKAs in 11 national or regional arthroplasty registries from 2010 to 2020. The 1-year risk of revision for PJI in TKAs with ALBC vs. PBC among patients with high American Society of Anesthesiologists (ASA) classification, body mass index (BMI), and/or diabetes was compared. Cumulative percent revision (1 minus Kaplan-Meier) based on 685,818 TKAs and Cox regression analyses (adjusted Hazard Rate Ratios [aHRRs]) were performed for TKAs with ALBC (reference) vs. PBC restricted to the following high-risk subgroups of patients: (1) ASA ≥3 (n = 335,612 vs. 35,997), (2) BMI ≥35 (n = 278,927 vs. 24,737), (3) ASA ≥3 and BMI ≥35 (n = 99,407 vs. 11,407), (4) diabetes (n = 38,341 vs. 21,838), and (5) ASA ≥3, BMI ≥35, and diabetes (n = 3,347 vs. 4,261). Advanced distributed meta-analyses were performed to combine all aggregate data and assess 1-year risk of revision for PJI.Results:Each registry reported a 1-year cumulative percent revision of ≤1.6% for PJI following TKAs both for ALBC and PBC in all high-risk subgroups. Similar 1-year risks of revision for PJI were found in TKAs with ALBC (reference) and PBC among patients with ASA ≥3 (aHRR: 1.09; 95% CI, 0.90-1.31); BMI ≥35 (1.06; 0.54-2.12); ASA ≥3 and BMI ≥35 (1.12; 0.83-1.50); diabetes (0.95; 0.74-1.20); and ASA ≥3, BMI ≥35, and diabetes (1.40; 0.86-2.29).Conclusions and Relevance:Similar 1-year revision risk of PJI was found for TKAs with ALBC vs. PBC in high-risk patients. Confirmation of the efficacy of ALBC in high-risk TKA patients needs to be evaluated in clinical trials.Level of Evidence:Level III. See Instructions for Authors for a complete description of levels of evidence.

ObjectiveThis study evaluated the effects of a 6-week osteoarthritis (OA) exercise and education intervention on metabolic health markers, including blood pressure (BP), glycated haemoglobin (HbA1c), high-density lipoprotein (HDL), cholesterol levels and weight in individuals with both OA and diabetes.MethodsData originated from the Swedish Osteoarthritis and Diabetes cohort, which is composed of the Swedish Osteoarthritis Register (SOAR) and National Diabetes Register. We included individuals diagnosed with OA and diabetes who underwent the intervention between January 2008 and December 2019, matched with controls with diabetes who did not based on birth year, sex, OA site (hip/knee) and OA diagnosis year. Outcomes included BP, HbA1c, HDL, total cholesterol levels and weight measured up to 3 years before and after SOAR enrolment. Statistical analyses used two-way fixed-effect models.ResultsThe study included 4571 individuals with OA and diabetes (mean age: 69.5, SD: 7.8; women: 52.7%; knee OA: 71.2%) and 7925 controls. The intervention group showed a systolic BP decrease of approximately 1.0 mm Hg at 6 and 12 months compared with the control group. HDL levels increased by about 0.02 mmol/L at 12, 18 and 24 months. Weight decreased by approximately 0.5 kg at 6, 18 and 30 months. HbA1c levels increased by approximately 0.5 mmol/mol at 6 months. No essential differences were found in the total cholesterol levels.ConclusionAn OA exercise and education intervention designed following OA clinical practice guidelines led to small and unlikely clinically relevant improvements in metabolic health markers in individuals with OA and diabetes.

Short-stem total hip arthroplasty (THA) may have bone sparing properties, which could be advantageous in a younger population with high risk of future revision surgery. We used data from the AOANJRR, LROI and SAR to compare survival rates of primary THA, stems used in the first-time revision procedures as well as the overall survival of first-time revisions between a cohort of short-stem and standard-stem THA.Short-stem THAs (designed as a short stem with mainly metaphyseal fixation) between 2007 and 2021 were identified (n=16,258). A propensity score matched cohort (1:2) with standard THAs in each register was identified (n=32,515). The cohorts were merged into a research dataset. Overall survival at 12 years follow-up was calculated using Kaplan-Meier survival analyses. Stem revisions (short-stem THA n=239, standard-stem THA n=352) were identified. The type of revision stem was classified as standard (&lt;160 mm) or long (&gt;160 mm). The survival rate of all first-time revisions in the two groups was calculated using any type of revision as outcome.The 12 year- overall survival rate (all revisions, all causes) for primary short-stem THAs was 95.3% (CI 94.5–95.9%), which was comparable to 95.2% (CI 94.7–95.7%) for standard-stem THAs. In the short-stem THA group, a standard stem (&lt;160 mm) was more often (59%) used in the first-time revision than in the standard-stem group (47%, p=0.004). The overall survival of the first-time revisions did not differ between cases primarily operated with a short or a standard stem.In our multi-national register study, the overall survival rate of short stems was similar to that of standard stems. In short stem revisions there was a higher likelihood of using a standard-length stem for the revision compared with first-time revisions of standard stems. This finding might indicate bone-sparing properties with short-stemmed THAs.

<b>Background:</b> Survival in infants born at the borderline of viability has increased while new ventilation strategies have emerged. Aim:&nbsp;To assess how ventilation strategies and increased survival at lower gestational ages (GA) affected the incidence of bronchopulmonary dysplasia (BPD) in Sweden over a decade. <b>Methods:</b> National register data of live-born infants at GA 22-26 weeks were compared for survival, BPD, severe BPD, and BPD or death in 2004-2007 (n=702) and 2014-2016 (n=885). Ventilation strategies and interventions were analyzed. <b>Results:</b> Median days on mechanical ventilation increased from 9 to 16 days (P&lt;0.001),&nbsp;including increased use of high-frequency oscillatory ventilation, from median 0 to 7 days (P&lt;0.001). High-flow nasal cannula (HFNC) was introduced between the two periods, and total days of CPAP + HFNC increased from 44 to 52 days; P&lt;0.001. Survival to 36 weeks’ GA increased from 72% to 81%(P&lt;0.001). BPD, defined as use of extra oxygen or any respiratory support at 36 weeks, increased from 59% to 68% (P=0.002), but after adjustment for GA, birth weight, sex, SGA ,and Apgar score this was not significant (adj.OR 1.19,CI 0.92-1.54, P=0.20). Incidence of severe BPD, defined as either &gt;30% oxygen, CPAP or mechanical ventilation at 36 weeks, decreased from 25% to 21% (adj.OR 0.63,CI 0.47-0.85, P=0.003). The combined outcome of BPD or death increased from 70% to 74%, but this was not significant. <b>Conclusion:</b> A significantly increased survival at 22-26 weeks was associated with an increased time of invasive and non-invasive respiratory support. The risk of BPD increased from 59% to 67%, but in a multivariate analysis this was not significant, and the risk of severe BPD decreased significantly.

BackgroundDespite being the anchor drug for treating rheumatoid arthritis (RA), methotrexate (MTX) provides a good response only in some of the treated patients [1]. If MTX treatment outcome has a substantial genetic component, genetic variants could provide useful predictors for identification of patients likely to respond and remain on treatment. So far, studies have focused mainly on primary response, and attempts to explain the inter-patient variability through genetic variants have been inconclusive or underpowered [2,3].ObjectivesWe aimed to investigate whether there are genetic variants associated with persistence to treatment with MTX (at one and three years) in early RA, and to estimate any underlying heritability.MethodsWe conducted a genome-wide association study (GWAS) on persistence to treatment with MTX in DMARD-monotherapy. We included participants from the Epidemiological Investigation of RA (EIRA) study and the Swedish Rheumatology Quality Register’s biobank, diagnosed with early RA and treated with MTX as their first ever DMARD. Persistence to MTX was defined as remaining on treatment at one and three years, respectively, with no additional DMARDs added during that period. Estimation of SNP-based heritability was done using restricted maximum likelihood. We performed the analyses for all RA, and two disease subsets: those positive for either ACPA or rheumatoid factor, and those negative for both.ResultsAfter quality control, 3403 of an initial 3609 early RA patients of European ancestry and above five million SNPs remained for the primary analysis. Among these, 65% were persistent at one year, and 44% were persistent at three years. In secondary analysis we excluded 218 patients due to missing sero-status. Of the remaining, 72% were seropositive. No SNP reached genome-wide significance, neither for persistence at one nor at three years. The SNP-based heritability was estimated to 0.35 (95%CI 0.04-0.65) for persistence at one year and 0.09 (95%CI 0.00-0.37) for persistence at three years. Analyses stratified by sero-status provided results comparable to the main analysis with similar proportions of persistent patients and no SNP reaching genome-wide significance for any of the subgroups. Point estimates of heritability for persistence in the seropositive group at one year (h2 = 0.08, 95%CI 0.00-0.51) was lower than for seropositive persistence at three years (h2 = 0.19, 95%CI 0.00-0.62) while point estimates for the seronegative heritability were zero for both persistence outcomes.ConclusionDespite being the largest GWAS on an MTX treatment outcome to date, no genome-wide significant associations were detected. The low heritability observed along with the lack of strong independent associations, may indicate that genetic influence from common genetic variants on persistence to MTX is minor, and of a polygenic nature.