High dose dexamethasone in high pain responders undergoing total hip arthroplasty: A randomized controlled trial.

BACKGROUND: Postoperative pain after total hip arthroplasty (THA) may delay postoperative mobilization and discharge. Postoperative pain has been shown to be higher in pain catastrophisers and patients receiving opioids. A single dose of glucocorticoid reduces pain after THA, and an increased dose of glucocorticoids has been found to be effective in patients at high risk of postoperative pain after total knee arthroplasty (TKA), however, the ideal dose in THA remains unknown. OBJECTIVE: To evaluate the effect of a high dose (1 mg kg -1 ) vs. intermediate dose (0.3 mg kg -1 ) of dexamethasone on pain after THA. DESIGN: A randomized double-blind controlled study. SETTING: A two-centre study including two large arthroplasty sites in Denmark was conducted from February 2019 to August 2020. PATIENTS: A total of 160 patients undergoing THA by neuraxial block with multimodal analgesia, having a Pain Catastrophising Scale score >20 and/or preoperative opioid use were included. INTERVENTION: Patients were randomly assigned to receive dexamethasone 1 mg kg -1 or 0.3 mg kg -1 before THA. MAIN OUTCOME MEASURES: Primary outcome was percentage of patients experiencing moderate to severe pain (visual analogue scale, VAS > 30 mm on a 0 to 100 mm scale) on ambulating 24 h after surgery. Secondary outcomes included cumulated pain scores, C-reactive protein (CRP), opioid use, postoperative recovery scores, length of stay, complications, and re-admission within 30 and 90 days. RESULTS: No difference was found in percentage of VAS >30 mm 24 h after surgery in the 5-m walk test (VAS > 30/VAS ≤ 30%); 33/42 (44%) vs. 32/43 (43%), relative risk = 1.04 (95% confidence interval 0.72-1.51; P  = 0.814) in 1 mg kg -1vs. 0.3 mg kg -1 respectively. No differences were found in CRP and opioid use between groups. Also, no intergroup differences were found in recovery scores, re-admissions, or complications. CONCLUSION: 1 mg kg -1vs. 0.3 mg kg -1 dexamethasone improved neither postoperative pain nor recovery in THA in a cohort of predicted high pain responders. TRIAL REGISTRATION: ClinicalTrials.gov ID-number NCT03763760 and EudraCT-number 2018-2636-25.

Repeat dose steroid in high pain responders after total knee arthroplasty: A study protocol.

Pain after total knee arthroplasty (TKA) is a well-known clinical problem potentially delaying ambulation and recovery. Perioperative glucocorticoids reduce pain and facilitate early recovery, but the optimal timing and dose are still unknown. High pain catastrophizers have an increased risk of poorly controlled postoperative pain, and moderate to severe pain at 24 h is associated with a risk of pain relapse at 48 h. To evaluate the effect of a repeat moderate dose of glucocorticoids after TKA in high pain catastrophizers presenting with moderate to severe pain 24 h postoperatively, having received preoperative high-dose glucocorticoids. High pain catastrophizers (Pain Catastrophizing Scale > 20) undergoing TKA are screened 24 h postoperatively and are included if they experience moderate to severe pain (VAS > 30) during a 5 m walk test. The included patients will receive either oral 24 mg dexamethasone (n = 55) or placebo (n = 55) on the evening of Day 1 (~30-37 h) after surgery. In addition, patients receive a standard multimodal analgesic regimen, including paracetamol, celecoxib, local infiltration analgesia, and preoperative dexamethasone (1 mg/kg). Patients will fill out a pain diary for 7 days after surgery. The primary outcome is moderate to severe pain (VAS > 30) during a 5 m walk test on the morning of Day 2 after surgery. The secondary outcomes include cumulated pain at rest and during ambulation, cumulated use of rescue analgesics, quality of sleep, lethargy, dizziness, nausea, satisfaction with the analgesic regimen, length of stay, morbidity, mortality, and reasons for readmissions. Follow-up is at 8 and 30 days. The data from this study will provide evidence for the effect of a repeated dose of dexamethasone as an analgesic adjuvant in patients undergoing TKA with a high risk of postoperative pain.

High-dose dexamethasone in low pain responders undergoing total knee arthroplasty: a randomised double-blind trial.

BACKGROUND: Postoperative pain after total knee arthroplasty (TKA) is a continuing problem despite optimised multimodal analgesia. Previous studies have shown preoperative glucocorticoids to reduce postoperative pain, but knowledge about specific doses and effects in specific patient groups is lacking. METHODS: A two-centre, double-blind, two-arm study comparing preoperative dexamethasone (1 mg kg-1vs 0.3 mg kg-1 i.v.) on postoperative pain in 160 planned TKA subjects with low preoperative pain catastrophising and no opioid use. Subjects received multimodal analgesia with paracetamol, cyclooxygenase-2 inhibitors, local anaesthetic infiltration analgesia, and rescue opioids. The primary outcome was percentage of subjects experiencing moderate to severe pain (visual analogue scale >30 mm) upon ambulation at 24 h. Secondary outcomes included pain scores, postoperative inflammation (C-reactive protein), opioid and antiemetics use, and 'Quality of Recovery-15' and 'Opioid-Related Symptom Distress Scale', length of stay, readmissions, and complications up to Day 90. RESULTS: A total of 157 subjects (80 vs 77) were included. No difference was found between groups in the incidence of subjects experiencing visual analogue scale >30 on ambulation 24 h after surgery (56% vs 53%, relative risk =1.07, confidence interval: 0.8-1.4, P=0.65). No differences in other pain outcomes or use of rescue opioids and antiemetics, in Quality of Recovery-15 and Opioid-Related Symptom Distress Scale, length of stay, readmissions, or complications. C-reactive protein values were comparable at 24 h (13 [6-25] mg L-1vs 16 [9-38] mg L-1, P = 0.07), but lower at 48 h (26 [9-52] mg L-1vs 50 [30-72] mg L-1, P<0.01) in the high-dose group. CONCLUSION: Use of 1 mg kg-1vs 0.3 mg kg-1 i.v. dexamethasone in low pain responders after TKA did not improve early postoperative pain or other outcomes in contrast to benefits in a high pain responder population. CLINICAL TRIAL REGISTRATION: NCT03758170 (first registration 29-11-2018).

High-dose steroids in high pain responders undergoing total knee arthroplasty: a randomised double-blind trial.

BACKGROUND: Total knee arthroplasty (TKA) is associated with moderate-to-severe postoperative pain despite multimodal opioid-sparing analgesia. Pain catastrophising or preoperative opioid therapy is associated with increased postoperative pain. Preoperative glucocorticoid improves pain after TKA, but dose-finding studies and benefit in high pain responders are lacking. METHODS: A randomised double-blind controlled trial with preoperative high-dose intravenous dexamethasone 1 mg kg-1 or intermediate-dose dexamethasone 0.3 mg kg-1 in 88 patients undergoing TKA with preoperative pain catastrophising score >20 or regular opioid use was designed. The primary outcome was the proportion of patients experiencing moderate-to-severe pain (VAS >30) during a 5 m walk 24 h postoperatively. Secondary outcomes included pain at rest during nights and at passive leg raise, C-reactive protein, opioid use, quality of sleep, Quality of Recovery-15 and Opioid-Related Symptom Distress Scale, readmission, and complications. RESULTS: Moderate-to-severe pain when walking 24 h postoperatively was reduced (high dose vs intermediate dose, 49% vs 79%; P<0.01), along with pain at leg raise at 24 and 48 h (14% vs 29%, P=0.02 and 12% vs 31%, P=0.03, respectively). C-reactive protein was reduced in the high-dose group at both 24 and 48 h (both P<0.01). Quality of Recovery-15 was also improved (P<0.01). CONCLUSIONS: When compared with preoperative dexamethasone 0.3 mg kg-1 i.v., dexamethasone 1 mg kg-1 reduced moderate-to-severe pain 24 h after TKA and improved recovery in high pain responders without apparent side-effects. CLINICAL TRIAL REGISTRATION: NCT03763734.

EFORT recommendations for off-label use, mix & match and mismatch in hip and knee arthroplasty.

Off-label use is frequently practiced in primary and revision arthroplasty, as there may be indications for the application of implants for purposes outside the one the manufacturers intended.Under certain circumstances, patients may benefit from selective application of mix & match. This can refer to primary hip arthroplasty (if evidence suggests that the combination of devices from different manufacturers has superior results) and revision hip or knee arthroplasty (when the exchange of one component only is necessary and the invasiveness of surgery can be reduced).Within the EFORT 'Implant and Patient Safety Initiative', evidence- and consensus-based recommendations have been developed for the safe application of off-label use and mix & match in primary as well as revision hip and knee arthroplasty.Prior to the application of a medical device for hip or knee arthroplasty off-label and within a mix & match situation, surgeons should balance the risks and benefits to the patient, obtain informed consent, and document the decision process appropriately.Nevertheless, it is crucial for surgeons to only combine implants that are compatible. Mismatch of components, where their sizes or connections do not fit, may have catastrophic effects and is a surgical mistake.Surgeons must be fully aware of the features of the components that they use in off-label indications or during mix & match applications, must be appropriately trained and must audit their results.Considering the frequent practice of off-label and mix & match as well as the potential medico-legal issues, further research is necessary to obtain more data about the appropriate indications and outcomes for those procedures. Cite this article: EFORT Open Rev 2021;6:982-1005. DOI: 10.1302/2058-5241.6.210080.

Preoperative high-dose Steroids in Total Knee and Hip Arthroplasty - Protocols for three randomized controlled trials.

BACKGROUND: Patients undergoing total knee arthroplasty (TKA)/ total hip arthroplasty (THA) still experience moderate-severe postoperative pain despite optimized pain management regimes. The patients already on opioid treatment and pain catastrophizers (PCs) have a higher risk of postoperative pain. The use of preoperative intravenous high-dose glucocorticoids decreases postoperative pain after TKA and THA, but optimal dose is yet to be found, and the effect on subpopulations at high pain risk is unknown. AIM: To investigate the effect of a higher than previously used dose of glucocorticoids (dexamethasone (DXM)), administered intravenously before surgery, as part of standardized fast-track regimen, on postoperative pain in TKA/THA subgroups. METHOD: Three separate randomized, double-blinded, controlled trials were planned to compare a new higher dose DXM (1 mg/kg) to the earlier used high-dose DXM (0.3 mg/kg). Study 1: predicted Low Pain TKA; study 2: predicted High Pain Responder (HPR) TKA; study 3: predicted HPR THA. Predicted HPR groups consist of either PCs with PCS-score of ≥ 21 and/or history of ongoing opioid-treatment of 30 mg/day of morphine or equivalents > 30 days. In total, 408 patients were planned for inclusion (160 Low Pain TKA, 88 HPR TKA, 160 HPR THA). PRIMARY OUTCOME: Pain upon ambulation in a 5-meter walk test 24 hours after surgery. Secondary outcomes include use of analgesics, rescue-opioids, antiemetics, cumulated pain, CRP, OR-SDS, QoR-15, quality of sleep, length of stay (LOS), reasons for hospitalization, readmission, morbidity, and mortality. Patients completed follow-up on day 90. Recruiting commenced February 2019 and is expected to finish in September 2020.

Survival and revision causes of hip resurfacing arthroplasty and the Mitch proximal epiphyseal replacement: results from the Danish Hip Arthroplasty Register.

Background and purpose - The Mitch proximal epiphyseal replacement (PER) was developed to preserve proximal femoral bone and minimize femoral neck fracture associated with hip resurfacing arthroplasty (HRA). We studied the survival and risk of revision of HRA compared with cementless metal-on-polyethylene (MoP) total hip arthroplasty (THA) and the survival and risk of revision of the Mitch PER compared with MoP THA.Patients and methods - Using propensity score, we matched 1,057 HRA to 1,057 MoP THA and 202 Mitch PER to 1,010 MoP THA from the Danish Hip Arthroplasty Register. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk.Results - The cumulative incidence for any revision of HRA at 10 years' follow-up was 11% (95% confidence interval [CI] 9.1-13) and 6.4% (CI 5.8-7.0) for MoP THA. The RR of any revision was 1.5 (CI 1.1-2.1) for HRA at 10 years' follow-up. By excluding the ASR components, the RR of revision at 10 years was 1.2 (CI 0.8-1.7). The cumulative incidence of revision was 9.6% (CI 4.2-18) for Mitch PER and 5.4% (CI 5.1-5.7) for MoP THA at 8 years. The RR of revision was 2.0 (CI 0.9-4.3) for Mitch PER at 8 years' follow-up.Interpretation - The HRA had increased risk of revision compared with the MoP THA. When excluding ASR, the HRA group had similar risk of revision compared with MoP THA. The Mitch PER did not have a statistically significant increased risk of revision compared with MoP THA.

Complications and readmissions following outpatient total hip and knee arthroplasty: a prospective 2-center study with matched controls.

Background and purpose - Outpatient arthroplasty has gained popularity in recent years; however, safety concerns still remain regarding complications and readmissions. In a prospective 2-center study we investigated early readmissions with overnight stay and complications following outpatient total hip (THA) and total knee arthroplasty (TKA) compared with a matched patient cohort with at least 1 postoperative night in hospital. Patients and methods - All consecutive and unselected patients scheduled for THA or TKA at 2 participating hospitals were screened for potential day of surgery (DOS) discharge. Patients who fulfilled the DOS discharge criteria were discharged home. Patients discharged on DOS were matched on preoperative characteristics using propensity scores to patients operated at the same 2 departments prior to the beginning of this study with at least 1 overnight stay. All readmissions within 90 days were identified. Results - It was possible to match 116 of 138 outpatients with 339 inpatient controls. Median LOS in the control cohort was 2 days (1-9). 7 (6%) outpatients and 13 (4%) inpatient controls were readmitted within 90 days. Readmissions occurred between postoperative day 2-48 and day 4-58 in the outpatient and control cohorts, respectively. Importantly, we found no readmissions within the first 48 hours and no readmissions were related to the DOS discharge. Interpretation - Readmission rates in patients discharged on DOS may be similar to matched patients with at least 1 overnight stay. With the selection criteria used, there may be no safety signal associated with same-day discharge.

Patients' experiences during the first 12 weeks after discharge in fast-track hip and knee arthroplasty - a qualitative study.

BACKGROUND: Due to the shortened length of stay in fast-track total hip and knee arthroplasty, patients must at a very early stage following surgery take responsibility for their postoperative care and treatment. It is important to establish if this treatment modality of fast-track is not only cost-effective, but meets patients' expectations and needs. AIM: To explore the lived experience of patients in fast-track total hip and knee arthroplasty during the first 12 weeks after discharge. METHODS: A phenomenological-hermeneutic approach was used inspired by Ricoeur's theory of narrative and interpretation. Data were collected through semi-structured interviews with 8 patients 2 and 12 weeks after discharge. FINDINGS: Through the structural analysis 3 themes emerged: 1) Dealing with transition between hospital and home, 2) Pain and self-management of medication, 3) Challenges in rehabilitation. CONCLUSION: Patients appreciated only 1 or 2 days in hospital. However, they were not sufficiently involved in the discharge planning. There was a feeling of uncertainty and being left on their own after discharge, which could affect their pain management and recovery at home. There is a need to develop in partnership with each individual patient a post discharge plan of care and rehabilitation to meet their individual needs, preferences and mode of motivation.

5-year clinical and radiographic follow-up of the uncemented Symax hip stem in an international study.

BACKGROUND: The uncemented Symax hip stem is developed through optimization of the uncemented Omnifit hip stem. The Symax stem design combines an anatomical anteverted proximal geometry with a straight distal section. The proximal part is coated with a biomimetic hydroxyapatite (HA) coating for improved osseointegration to enhance load transfer and to minimize proximal bone loss. The distal part is treated with an anodization surface treatment in order to prevent distal bone apposition, which is expected to prevent distal loading and reduce proximal stress shielding. Aim of this study is to report mid-term clinical performance and evaluate whether the radiographic features are in line with the design principles of the Symax hip. METHODS: The biomimetic hydroxyapatite-coated uncemented Symax hip stem was evaluated in 80 patients during a 5-year prospective clinical international study. Harris Hip Score (HHS), Oxford Hip Score (OHS), and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were performed preoperatively and postoperatively at 6 months and 1, 2, 3 and 5 years. Anteroposterior radiographs of the pelvis and axial radiographs of the operated hips were evaluated immediately postoperative and at follow-up 6 months and 1, 2, 3, and 5 years. Wilcoxon signed-rank test was used to analyse whether clinical outcome scores changed statistically significant over time. The overall percentage of agreement between two radiology assessment teams was used to evaluate observer agreement of radiology results. The Cohen's Kappa was evaluated as a measure of reliability to quantify the agreement between raters, corrected for chance agreement. RESULTS: Clinical outcome scores were excellent at 5 years with mean HHS of 98.1, mean OHS of 16.2 and mean WOMAC of 6.9. Only 2.7% of the patients had pain at rest or on weight-bearing, and mid-thigh pain was reported by 1.4% of the patients after 5 years. The percentage of agreement between radiology assessment teams was 94 to 100%, except for distal line formation (48%). Radiographic evaluation showed stable stems and signs of excellent progressive proximal fixation and favourable bone remodeling. CONCLUSIONS: The excellent mid-term clinical and radiographic performances are in line with the design principles and coating properties of this new implant and earlier published results. TRIAL REGISTRATION: http://ClinicalTrials.gov , NCT03469687 . Registered 19 March 2018 - Retrospectively registered.

European guidelines on perioperative venous thromboembolism prophylaxis: Day surgery and fast-track surgery.

: In recent years, day surgery and fast-track surgery have experienced a continuous increase in volume. Many procedures are now performed on an outpatient protocol, including general, orthopaedic, oncological, reconstructive or vascular surgery. The management of these patients is safe, but the incidence of venous thromboembolism in this population remains unknown. Several risk factors can be identified and stratified derived from studies of inpatient surgical management (e.g. Caprini score). Recommendations for thromboprophylaxis should be tailored from the assessment of both personal and procedure-related risk factors, although with a lack of evidence for application in outpatient management. For patients undergoing a low-risk procedure without additional risk factors, we recommend only general measures of thromboprophylaxis (early ambulation, optimal hydration) (Grade 1B). For patients undergoing a low-risk procedure with additional risk factors, or a high-risk procedure without additional risk factors, we recommend general measures of thromboprophylaxis (Grade 1B) and we suggest the administration of pharmacological prophylaxis with low molecular weight heparins (Grade 2B). For patients undergoing a high-risk procedure with additional risk factors we recommend general measures of thromboprophylaxis (Grade 1B) and pharmacological prophylaxis with low molecular weight heparins over other drugs (Grade 1B), or suggest specific mechanical measures in case of increased bleeding risk (Grade 2C). Pharmacological prophylaxis should last a minimum of 7 days (Grade 1B), although in selected cases of fast-track surgery, thromboprophylaxis could be limited to hospitalisation only (Grade 2C) and in specific cases of high-risk procedures, thromboprophylaxis could be extended for up to 4 weeks (Grade 2B).

Up to 10-year follow-up of the Symax stem in THA: a Danish single-centre study.

INTRODUCTION: The design of the cementless Symax-HA femoral stem is based on geometrical analysis of human femoral anatomy to optimise the fit within the femur. The stem combines an anatomical proximal section enabling a metaphyseal anchorage with a straight distal section. This results in an improved proximal load transfer. We aimed to determine the overall survival of total hip arthroplasty (THA) in patients operated at our institution with the Symax stem. Secondly, we investigated the cause of revision for patients having THA including the Symax stem. METHODS: The study is a registry study with results from a single centre, Vejle Hospital. From the Danish Hip -Arthroplasty Registry, we identified all THAs operated with the Symax stem. The primary outcome was revision. The secondary outcomes were aseptic loosening, periprosthetic fracture, and all other causes for revision. RESULTS: In total, 1,055 THAs were performed in 875 patients. The median 6.5-year survival rate was 97.5% (95% confidence interval [CI]: 96.6%-98.3%). 29 THAs had undergone revision due to the following causes: periprosthetic fracture (n = 11); aseptic loosening of the cup (n = 1); infection (n = 5); dislocation (n = 10); and component failure (n = 2). There was no revision due to aseptic loosening of the stem. CONCLUSIONS: From the Danish Hip Arthroplasty Registry, we identified the overall 6.5-year survival rate to be 95% for cementless THAs. In the present study, the Symax stem has a median 6.5-year survival rate at 97.5% (96.6%-98.3%). No revisions were due to aseptic loosening but the stem had a relative high prevalence of periprosthetic fractures.

Modular Neck vs Nonmodular Femoral Stems in Total Hip Arthroplasty-Clinical Outcome, Metal Ion Levels, and Radiologic Findings.

BACKGROUND: Modular neck femoral stem (MNFS) for total hip arthroplasty (THA) was introduced to optimize the outcome, but created concerns about pain, elevated blood metal ion levels, and adverse reaction to metal debris such as pseudotumors (PTs), related to corrosion between femoral neck and stem. We compared these outcomes in patients with MNFS or nonmodular femoral stem (NFS) THA. METHODS: Thirty-three patients with unilateral MNFS THA were compared with 30 patients with unilateral NFS THA. Levels of pain, serum cobalt, serum chromium were determined. Magnetic resonance imaging was performed to describe PT and fatty atrophy of muscles. RESULTS: The MNFS and NFS group had a mean follow-up of 2.3 and 3.1 years, respectively. Four and 13 patients in the MNFS and NFS group had pain, respectively (P = .005). The MNFS group had higher levels of serum cobalt (P < .0001) and chromium (P = .006). PTs were present in both the MNFS (n = 15) and NFS (n = 7) groups (P = .066). PTs were related to serum cobalt (P = .04) but not to pain or serum chromium. Fatty atrophy prevalence in the piriformis and gluteal muscles were higher in patients with MNFS (P = .009 and P = .032, respectively). CONCLUSION: More patients in the NFS group had pain. Serum cobalt and chromium levels were higher in the MNFS group. Prevalence of PTs was twice as high in the MNFS group, but the difference was insignificant.

Feasibility of outpatient total hip and knee arthroplasty in unselected patients.

Background and purpose - The number of patients who are suitable for outpatient total hip and knee arthroplasty (THA and TKA) in an unselected patient population remains unknown. The purpose of this prospective 2-center study was to identify the number of patients suitable for outpatient THA and TKA in an unselected patient population, to investigate the proportion of patients who were discharged on the day of surgery (DOS), and to identify reasons for not being discharged on the DOS. Patients and methods - All consecutive, unselected patients who were referred to 2 participating centers and who were scheduled for primary THA and TKA were screened for eligibility for outpatient surgery with discharge to home on DOS. If patients did not fulfill the discharge criteria, the reasons preventing discharge were noted. Odds factors with relative risk intervals for not being discharged on DOS were identified while adjusting for age, sex, ASA score, BMI and distance to home. Results - Of the 557 patients who were referred to the participating surgeons during the study period, 54% were potentially eligible for outpatient surgery. Actual DOS discharge occurred in 13-15% of the 557 patients. Female sex and surgery late in the day increased the odds of not being discharged on the DOS. Interpretation - This study shows that even in unselected THA and TKA patients, same-day discharge is feasible in about 15% of patients. Future studies should evaluate safety aspects and economic benefits.

Legumain Regulates Differentiation Fate of Human Bone Marrow Stromal Cells and Is Altered in Postmenopausal Osteoporosis.

Secreted factors are a key component of stem cell niche and their dysregulation compromises stem cell function. Legumain is a secreted cysteine protease involved in diverse biological processes. Here, we demonstrate that legumain regulates lineage commitment of human bone marrow stromal cells and that its expression level and cellular localization are altered in postmenopausal osteoporotic patients. As shown by genetic and pharmacological manipulation, legumain inhibited osteoblast (OB) differentiation and in vivo bone formation through degradation of the bone matrix protein fibronectin. In addition, genetic ablation or pharmacological inhibition of legumain activity led to precocious OB differentiation and increased vertebral mineralization in zebrafish. Finally, we show that localized increased expression of legumain in bone marrow adipocytes was inversely correlated with adjacent trabecular bone mass in a cohort of patients with postmenopausal osteoporosis. Our data suggest that altered proteolytic activity of legumain in the bone microenvironment contributes to decreased bone mass in postmenopausal osteoporosis.

Oral Midodrine Hydrochloride for Prevention of Orthostatic Hypotension during Early Mobilization after Hip Arthroplasty: A Randomized, Double-blind, Placebo-controlled Trial.

BACKGROUND: Early postoperative mobilization is essential for rapid recovery but may be impaired by orthostatic intolerance (OI) and orthostatic hypotension (OH), which are highly prevalent after major surgery. Pathogenic mechanisms include an insufficient postoperative vasopressor response. The oral α-1 agonist midodrine hydrochloride increases vascular resistance, and the authors hypothesized that midodrine would reduce the prevalence of OH during mobilization 6 h after total hip arthroplasty relative to placebo. METHODS: This double-blind, randomized trial allocated 120 patients 18 yr or older and scheduled for total hip arthroplasty under spinal anesthesia to either 5 mg midodrine hydrochloride or placebo orally 1 h before mobilization at 6 and 24 h postoperatively. The primary outcome was the prevalence of OH (decrease in systolic or diastolic arterial pressures of > 20 or 10 mmHg, respectively) during mobilization 6 h after surgery. Secondary outcomes were OI and hemodynamic responses to mobilization at 6 and 24 h. RESULTS: At 6 h, 14 (25%; 95% CI, 14 to 38%) versus 23 (39.7%; 95% CI, 27 to 53%) patients had OH in the midodrine and placebo group, respectively, relative risk 0.63 (0.36 to 1.10; P = 0.095), whereas OI was present in 15 (25.0%; 15 to 38%) versus 22 (37.3%; 25 to 51%) patients, relative risk 0.68 (0.39 to 1.18; P = 0.165). At 24 h, OI and OH prevalence did not differ between groups. CONCLUSIONS: Preemptive use of oral 5 mg midodrine did not significantly reduce the prevalence of OH during early postoperative mobilization compared with placebo. However, further studies on dose and timing are warranted since midodrine is effective in chronic OH conditions.

The "true" incidence of surgically treated deep prosthetic joint infection after 32,896 primary total hip arthroplasties: a prospective cohort study.

BACKGROUND AND PURPOSE: It has been suggested that the risk of prosthetic joint infection (PJI) in patients with total hip arthroplasty (THA) may be underestimated if based only on arthroplasty registry data. We therefore wanted to estimate the "true" incidence of PJI in THA using several data sources. PATIENTS AND METHODS: We searched the Danish Hip Arthroplasty Register (DHR) for primary THAs performed between 2005 and 2011. Using the DHR and the Danish National Register of Patients (NRP), we identified first revisions for any reason and those that were due to PJI. PJIs were also identified using an algorithm incorporating data from microbiological, prescription, and clinical biochemistry databases and clinical findings from the medical records. We calculated cumulative incidence with 95% confidence interval. RESULTS: 32,896 primary THAs were identified. Of these, 1,546 had first-time revisions reported to the DHR and/or the NRP. For the DHR only, the 1- and 5-year cumulative incidences of PJI were 0.51% (0.44-0.59) and 0.64% (0.51-0.79). For the NRP only, the 1- and 5-year cumulative incidences of PJI were 0.48% (0.41-0.56) and 0.57% (0.45-0.71). The corresponding 1- and 5-year cumulative incidences estimated with the algorithm were 0.86% (0.77-0.97) and 1.03% (0.87-1.22). The incidences of PJI based on the DHR and the NRP were consistently 40% lower than those estimated using the algorithm covering several data sources. INTERPRETATION: Using several available data sources, the "true" incidence of PJI following primary THA was estimated to be approximately 40% higher than previously reported by national registries alone.

Comparison of the risk of revision in cementless total hip arthroplasty with ceramic-on-ceramic and metal-on-polyethylene bearings.

BACKGROUND AND PURPOSE: Ceramic-on-ceramic (CoC) bearings were introduced in total hip arthroplasty (THA) to reduce problems related to polyethylene wear. We compared the 9-year revision risk for cementless CoC THA and for cementless metal-on-polyethylene (MoP) THA. PATIENTS AND METHODS: In this prospective, population-based study from the Danish Hip Arthroplasty Registry, we identified all the primary cementless THAs that had been performed from 2002 through 2009 (n = 25,656). Of these, 1,773 THAs with CoC bearings and 9,323 THAs with MoP bearings were included in the study. To estimate the relative risk (RR) of revision, we used regression with the pseudo-value approach and treated death as a competing risk. RESULTS: 444 revisions were identified: 4.0% for CoC THA (71 of 1,773) and 4.0% for MoP THA (373 of 9,323). No statistically significant difference in the risk of revision for any reason was found for CoC and MoP bearings after 9 years of follow-up (adjusted RR = 1.3, 95% CI: 0.72-2.4). Revision rates due to component failure were 0.5% (n = 8) for CoC bearings and 0.1% (n = 6) for MoP bearings (p < 0.001). 6 patients with CoC bearings (0.34%) underwent revision due to ceramic fracture. INTERPRETATION: When compared to the "standard" MoP bearings, CoC THA had a 33% higher (though not statistically significantly higher) risk of revision for any reason at 9 years.

Hip dislocations after 2,734 elective unilateral fast-track total hip arthroplasties: incidence, circumstances and predisposing factors.

STUDY DESIGN: Retrospective review of prospectively collected data. OBJECTIVE: To investigate the incidence of hip dislocation 90 days after total hip arthroplasty in relation to time after surgery, mechanism of dislocation and predisposing factors. METHODS: Prospective data on preoperative patient characteristics from six Danish arthroplasty departments with similar fast-track approaches were cross-referenced with the Danish National Patient Registry for complete 90-day follow-up on readmissions, including emergency-room contacts. Complete patient files and postoperative radiographs were reviewed in case of dislocations. Unadjusted comparisons were made using t test/Chi-square analyses, while evaluation of risk factors potentially predisposing to dislocations was done using uni- and multivariate regression analysis. RESULTS: A total of 2,734 consecutive unselected procedures were available for analysis, of which 65 (2.4 %) had dislocations. Of these, eight were during index admission and five were treated and discharged from the emergency room. Mechanisms of dislocation were most often movement while supine or sitting for the first 30 days and due to squatting/bending from day 31 to 90. The 65 patients with dislocations had suboptimal cup placement in 34 (52.3 %), and a femoral head size of <36 mm in 20 (30.8 %) cases. Predisposing factors of dislocation were age ≥75 [OR:1.96 (1.18-3.38)], pharmacologically treated psychiatric disease [OR:2.37 (1.29-4.36)] and department of surgery [OR:2.27 (1.31-3.40)] but not hospital stay of <4 days. Departments with recommendations for activity restrictions had fewer dislocations than a department without restrictions. CONCLUSIONS: Patients ≥75 years and with pharmacologically treated psychiatric disease may be at increased risk of dislocations after fast-track total hip arthroplasty. Further studies including detailed information on patient and prosthesis characteristics, and activity restrictions are needed to reduce the risk of dislocation.