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.

Psychopharmacological treatment in patients planned for hip or knee replacement.

Psychopharmacological treatment may be an independent risk factor for increased length of stay and readmission after hip and knee replacement. Thus, temporary perioperative discontinuation may be beneficial. However, little is known regarding the treatments, and not all are feasible to discontinue. Therefore, the aim of this study was to describe the treatments in terms of type, dose, duration, indication and initiating physician to assess the feasibility of temporary perioperative discontinuation. We included 482 patients planned for hip or knee replacement in psychopharmacological treatment for psychiatric disorders from 2021 to 2023 at five orthopaedic departments in Denmark. Most patients were treated with antidepressants (89%); most frequently, either selective serotonin reuptake inhibitors (SSRIs; 48%) or serotonin-norepinephrine reuptake inhibitors (SNRIs; 21%). The majority received monotherapy (70%); most frequently, an SSRI (36%) or an SNRI (12%). Most antidepressants were initiated by general practitioners (71%), and the treatments had lasted for more than a year (87%). The doses of SSRIs/SNRIs were moderate, and the most frequent indication for antidepressants was depression (77%). These results imply that temporary perioperative SSRI/SNRI discontinuation may be feasible in hip and knee replacement patients and support a future randomized controlled trial investigating the potential benefits of temporary discontinuation.

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.

Use of a tourniquet is not associated with increased risk of venous thromboembolism after fast-track total knee arthroplasty: a prospective multicenter cohort study of 16,250 procedures.

BACKGROUND AND PURPOSE: Venous thromboembolism (VTE) is a serious postoperative complication after total knee arthroplasty (TKA). Use of a tourniquet has shown conflicting results for risk of VTE after TKA. We aimed to investigate the associated risk of VTE after TKA using tourniquet in a fast-track set-up as no previous data exists. PATIENTS AND METHODS: We performed an observational cohort study from 9 fast-track centers including unilateral primary TKA from 2010-2017 with prospective collection of preoperative risk-factors and complete 90-day follow-up. Use of a tourniquet was registered in the Danish Knee Arthroplasty Register. Postoperative VTE was identified from health records. We performed risk analyses using a mixed-effects logistic regression model adjusting for previously identified risk factors. RESULTS: Of the 16,250 procedures (39% males, mean age 67.9 [SD 10.0] years, median LOS 2 [interquartile range 2-3]) 12,518 (77%) were performed with a tourniquet. The annual tourniquet usage varied greatly between departments from 0% to 100%, but also within departments from 0% to 99%. There was no significant difference between the 2 groups with 52 (0.42%) VTEs in the tourniquet group vs. 25 (0.67%) in the no-tourniquet group (p = 0.06 for cumulative 90-day incidence of VTE). This association remained statistically insignificant for VTE using tourniquet after adjustment for previously identified risk factors. CONCLUSION: We found no association between the use of a tourniquet and increased risk of 90-day VTE after primary fast-track TKA, irrespective of the length of time for which the tourniquet was applied.

Complications after lateral unicompartmental knee arthroplasty in a fast-track setting: a prospective cohort study of 170 procedures.

BACKGROUND AND PURPOSE: In existing studies on fasttrack unicompartmental knee arthroplasty (UKA), the majority of surgeries are medial. There are substantial differences between lateral and medial UKA, which is why outcomes cannot automatically be compared. To gain information on the feasibility and safety of fast-track protocols in lateral UKAs, we investigated length of stay (LOS) and early complications after lateral UKA, performed using a fast-track protocol in well-established fast-track centers. PATIENTS AND METHODS: We retrospectively evaluated prospectively collected data on patients undergoing lateral UKA in a fast-track setup from 2010 to 2018 at 7 Danish fast-track centers. Data on patient characteristics, LOS, complications, reoperations, and revisions was analyzed using descriptive statistics. Safety and feasibility were defined as complication and reoperation rates within 90 days comparable to non-fast track lateral UKA or fast-track medial UKA. RESULTS: We included 170 of patients with a mean age of 66 (SD 12) years. Median LOS was 1 day (interquartile range 1-1), which was unchanged from 2012-2018. 18% were discharged on the day of surgery. Within 90 days, 7 patients experienced medical complications and 5 patients experienced surgical complications. 3 patients underwent reoperation, 2 were soft tissue revisions and the third was removal of an exostosis due to catching of the patella. 1 patient was revised due to a bearing dislocation. CONCLUSION: Our findings suggest that lateral UKA in a fast-track setting is feasible and safe.

Study protocol for discharge on day of surgery after hip and knee arthroplasty from the Center for Fast-track Hip and Knee Replacement.

BACKGROUND AND PURPOSE: Limited data exists on the implementation process and safety of discharge on the day of surgery after primary hip and knee arthroplasty in a multicenter setting. We report our study protocol on the investigation of the feasibility, safety, and socioeconomic aspects following discharge on day of surgery after hip and knee arthroplasty across 8 fast-track centers. PATIENTS AND METHODS: This is a study protocol for a prospective cohort study on discharge on day of surgery from the Center for Fast-track Hip and Knee Replacement. The collaboration includes 8 centers covering 40% of the primary hip and knee arthroplasty procedures undertaken in Denmark. All patients scheduled for surgery are screened for eligibility using well-defined inclusion and exclusion criteria. Eligible patients fulfilling discharge criteria will be discharged on day of surgery. We expect to screen 9,000 patients annually. Duration and outcome: Patients will be enrolled over a 3-year period from September 2022 and reporting of results will run continuously until December 2025. We shall report the proportion of eligible patients and patients discharged on day of surgery as well as limiting factors. Readmissions and complications within 30 days are recorded with real-time follow-up by research staff. Furthermore, patient-reported information on willingness to repeat discharge on day of surgery, contacts with the healthcare system, complications, and workability is registered 30 days postoperatively. EQ-5D, Oxford Knee Score, and Oxford Hip Score are completed preoperatively and after 3 months and 1 year. Finally, outcome data will be used in the development of a prediction model for successful discharge on the day of surgery.

Preoperative prescriptions and polypharmacy in elective total hip and knee arthroplasty from 2010 to 2017, a descriptive cohort study.

BACKGROUND: Evaluation of regular medication is an essential part of the preanesthetic consultation. However, even in elective surgical patients, such as those scheduled for total hip (THA) and knee arthroplasty (TKA), this task may be increasingly complex due to increasing age and number of pharmacologically treated comorbidities. Nevertheless, data on prescribed drugs and polypharmacy in elective surgical patients is sparse. METHODS: Descriptive study in elective unilateral fast-track THA and TKA between 2010 and 2017 based on data from the Centre for fast-track Hip and Knee Replacement Database. Nationwide information on dispensed prescriptions up to 3 months preoperatively was acquired from the Danish National Database of Reimbursed Prescriptions. Drugs were divided into individual subgroups according to the fourth Anatomical Therapeutic Chemical level (ATC4). Primary outcome was changes in the median number of prescribed drugs/year. Secondarily, we investigated the fraction of patients with polypharmacy (≥5 individual ATC4-subgroups), severe polypharmacy (≥10) and specific drugs of relevance at the preanesthetic evaluation. RESULTS: Of 36,934 procedures in 32,515 patients with a median age of 69 years, we found a median of 3 ATC4-subgroups with no time-related changes regardless of year of surgery but increasing in patients ≥65 years (median: 3 [IQR: 2-4]) versus < 65 years (2 [IQR 1-3]; p < .001). In total, 35.1% and 4.2% had polypharmacy or severe polypharmacy. There was a significant declining trend in severe polypharmacy from 2010 to 2017 (p = .003). Drugs of anesthetic relevance were used by 41.1% of all patients, most often ANG-II or ACE inhibitors and betablockers, which were used by 28.0% and 15.7%. Oral antihyperglycemics was used by 7.8% and 2.0% used insulin. Only 4.0% and 2.1% of patients used vitamin-K antagonists and direct oral anticoagulants, respectively. MAO-inhibitors/Lithium salts were used by 0.3%. The combination of ANG-II/ACE inhibitors, a diuretic and NSAID ("triple whammy") was present in 4.3% of all patients. CONCLUSION: Patients scheduled for elective THA and TKA used a median of 3 prescribed drugs. However, 1/3 of patients qualified as having polypharmacy and 41% used drugs requiring anesthetic consideration when planning for surgery.

Fast-track revision hip arthroplasty: a multicenter cohort study on 1,345 elective aseptic major component revision hip arthroplasties.

BACKGROUND AND PURPOSE: Data on application of fasttrack/enhanced recovery protocols in revision hip arthroplasty (R-THA) surgery is scarce. We report length of stay (LOS), risk of LOS > 5 days, and readmission ≤ 90 days after revision hip arthroplasty in centers with a well-established fast-track protocol in both primary and revision procedures. PATIENTS AND METHODS: This is an observational cohort study from the Centre for Fast-track Hip and Knee Replacement and the Danish Hip Arthroplasty Register. Consecutive elective aseptic major component revision hip arthroplasties from 6 dedicated fast-track centers from 2010 to 2018 were included. RESULTS: 1,345 R-THAs were analyzed, including 23% total revisions, 52% acetabular component revisions, and 25% femoral component revisions. Mean age was 70 years (SD 12) and 61% were female. Median LOS was 3 days (interquartile range [IQR] 2-6), decreasing from median 6 (IQR 3-10) days in 2010 to 2 (IQR 1-4) days in 2018. The 90-day readmission rate was 20%, but showed a fluctuating and increasing trend from 13% in 2010 to 28% in 2018. Risk factors for LOS > 5 days and readmission were use of walking aid, preoperative hemoglobin ≤ 13 g/dL, pharmacological treated psychiatric disorder, age ≥ 80 years, age 70-79 years (only LOS > 5 days), cardiac disease (only LOS > 5 days), pulmonary disease (only readmission), BMI ≥ 35 (only LOS > 5 days) and ≥ 1 previous revision (only LOS > 5 days). INTERPRETATION: LOS decreased to median 2 days at the end of the study period, but the 90 days readmission risk remained high (> 20%). Several risk factors for postoperative complications were identified, suggesting that at-risk patients should be treated using an extended fast-track/enhanced recovery protocol focusing on preoperative optimization and postoperative monitoring as well as surgical techniques to reduce hip dislocations.

Fast-track revision knee arthroplasty.

BACKGROUND: Limited data exist on fast-track protocols in relation to revision knee arthroplasty. Hence, the aim of this study was to report length of stay (LOS), risk of LOS > 5 days and readmission ≤ 90 days after revision knee arthroplasty in centers with a well-established fast-track protocol in both primary and revision surgery. METHODS: An observational cohort study from the Centre for Fast-track Hip and Knee Replacement and the Danish Knee Arthroplasty Register. We included elective aseptic major component revision knee arthroplasties consecutively from 6 dedicated fast-track centers from 2010 to 2018. RESULTS: 1439 revision knee arthroplasties were analyzed, including 900 total revisions, 171 large partial revisions (revision of either femoral or tibia component) and 368 revisions of unicompartmental knee arthroplasty (UKA) to total knee arthroplasty (TKA). Mean age was 65 years (SD 10.9) and 66% were females. Mean LOS was 3.7 days (SD 3.9) in the study period, but decreased to 2.4 days (SD 1.3) in 2018. Risk factors for LOS > 5 days was ≥ 1 previous revision, use of walking aid, BMI > 35, ages < 50, 70-79 and ≥ 80 years, whereas revision of UKA to TKA and large partial revision were negatively associated. The 90-day readmission and mortality risk was 9.1% and 0.5%. Cardiac disease and use of walking aid were associated with increased risk of readmission ≤ 90 days. CONCLUSION: Elective aseptic major component revision knee arthroplasty using similar fast-track protocols as in primary TKA is safe with short and decreasing LOS.

Influence of body mass index and age on day-of-surgery discharge, prolonged admission, and 90-day readmission after fast-track unicompartmental knee arthroplasty.

Background and purpose - The indications for unicompartmental knee arthroplasty (UKA) have become less restrictive and, today, high age and high BMI are not considered contraindications by many surgeons. While the influence of these patient characteristics on total knee arthroplasty is well documented, evidence on UKA is lacking. We investigated the effect of BMI and age on day of surgery (DOS) discharge, prolonged admission, and 90-day readmission following UKA surgery.Patients and methods - This retrospective cohort study included 3,897 UKA patients operated on between 2010 and 2018 in 8 fast-track arthroplasty centers. Patients were divided into 5 BMI groups and 5 age groups. Differences between groups in the occurrence of DOS discharge, prolonged admission > 2 days, and 90-day readmission was investigated using a chi-square test and mixed-effect models adjusted for patient characteristics using surgical center as a random effect.Results - Median LOS was 1 day. DOS discharge was achieved in 26% of patients with no statistically significant differences between BMI groups. DOS discharge was less likely in UKA patients aged > 70 years (age 71-80; odds ratio [OR] 0.7 [95% CI 0.6-0.9]). Prolonged admission was not affected by BMI or age in the adjusted analysis. 90-day readmission was more likely in patients with BMI > 35 (OR 1.9 [CI 1.1-3.1]) and patients aged 71-80 (OR 1.5 [CI 1.1-2.1]).Interpretation - Age > 70 years decreased the likelihood of DOS discharge after UKA. High BMI as well as advanced age increased the likelihood of 90-day readmission. This should be noted by surgeons operating on patients with high BMI and age.

Length of Stay and 90-Day Readmission/Complication Rates in Unicompartmental Versus Total Knee Arthroplasty: A Propensity-Score-Matched Study of 10,494 Procedures Performed in a Fast-Track Setup.

BACKGROUND: Whether to use unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA) for appropriate osteoarthritis cases is a subject of debate. UKA potentially offers faster recovery and fewer short-term complications. However, reported differences in preoperative comorbidity between TKA and UKA-treated patients could affect outcomes. The aim of this study was to investigate differences in the length of the postoperative hospital stay (LOS) as well as readmissions and complications within 90 days after surgery between matched UKA and TKA cohorts. METHODS: Patients undergoing UKA or TKA in a fast-track setup at 9 orthopaedic centers from 2010 to 2017 were included in the study. Propensity score matching with exact matching for surgical year was used to address differences in demographics and comorbidity between the UKA and TKA groups, resulting in a matched cohort of 2,786 patients who underwent UKA and 7,708 who underwent TKA. Univariable linear or logistic regression models, multivariable mixed-effects models, and a chi-square test were used to investigate differences in LOS, readmissions, and complications between the UKA and TKA groups. RESULTS: The UKA group had a shorter median LOS than the TKA group (1 compared with 2 days, p < 0.001). The UKA group was more likely to be discharged on the day of surgery (21.1% compared with 0.5%, odds ratio [OR] = 38.5, 95% confidence interval [CI] = 27.0 to 52.6) and less likely to have an LOS of >2 days (OR = 0.20, 95% CI = 0.17 to 0.24) compared with the TKA group. There was no difference in the 90-day readmission rate (p = 0.611) between the groups. The UKA group had fewer periprosthetic joint infections (OR = 0.50, 95% CI = 0.26 to 0.99) and reoperations (OR = 0.40, 95% CI = 0.20 to 0.81) compared with the TKA group. However, aseptic revisions were more frequent in the UKA group (OR = 2.5, 95% CI = 1.1 to 6.0). CONCLUSIONS: The UKA group had shorter hospital stays, a higher rate of discharge on the day of surgery, and fewer periprosthetic joint infections and reoperations compared with the matched TKA group. However, the TKA group had fewer aseptic revisions. Our findings support the use of UKA in a fast-track setup when indicated. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Venous thromboembolism after fast-track elective revision hip and knee arthroplasty - A multicentre cohort study of 2814 unselected consecutive procedures.

BACKGROUND: Venous thromboembolism (VTE) prophylaxis is much debated within total hip and knee arthroplasty (THA/TKA). Revision hip and knee arthroplasty (rTHA/rTKA) are more extensive procedures, but data on the risk of postoperative VTE is conflicting and there are no specific guidelines for thromboprophylaxis. Furthermore, data on rTHA/rTKA within a fast-track protocol is sparse. Thus, we aimed at evaluating the incidence and time course of VTE in unselected elective rTHA/rTKA within our established multicentre fast-track collaboration with in-hospital only thromboprophylaxis if length of stay (LOS) ≤ 5 days. METHODS: We used an observational study design of unselected consecutive fast-track elective major component rTHA/rTKA from 6 dedicated fast-track centres between 2010 and 2018. We obtained information on revisions through Danish hip and knee arthroplasty registers and complete (>99%) 90 days follow-up through the Danish National Patient Registry in combination with chart review. RESULTS: We included 2814 procedures with median LOS 3 days [2-5] and 21% had LOS >5 days. The 90-day incidence of VTE was 0.42% (n = 12), with 8 (0.28%) DVT and 4 (0.14%) PE, after median 14 days [IQR: 11-23] with the latest on day 31. CONCLUSION: The 90-day incidence of VTE after elective fast-track rTHA and rTKA was about 0.4% which is comparable to the 90-day VTE incidence after primary fast-track THA, TKA and unicompartmental knee arthroplasty. Future investigations should focus on identification of high-risk patients while the surgical trauma per se may be less important.

Improvement in fast-track hip and knee arthroplasty: a prospective multicentre study of 36,935 procedures from 2010 to 2017.

"Fast-track" protocols has improved surgical care with a reduction in length of hospital stay (LOS) in total hip (THA) and knee arthroplasty (TKA). However, the effects of continuous refinement of perioperative care lack detailed assessment. We studied time-related changes in LOS and morbidity after THA and TKA within a collaboration with continuous scientific refinement of perioperative care. Prospective multicentre consecutive cohort study between 2010 and 2017 from nine high-volume orthopaedic centres with established fast-track THA and TKA protocols. Prospective collection of comorbidities and complete 90-day follow-up from the Danish National Patient Registry and medical records. Of 36,935 procedures median age was 69 [62 to 75] years and 58% women. LOS declined from three [two to three] days in 2010 to one [one to two] day in 2017. LOS > 4 days due to "medical" or "surgical" complications, and "with no recorded morbidity" declined from 4.4 to 2.7%, 1.5 to 0.6%, and 3.8 to 1.3%, respectively. 90-days readmission rate declined from 8.6 to 7.7%. Our multicentre study in a socialized healthcare setting was associated with a continuous reduction in LOS and morbidity after THA and TKA.

Venous thromboembolism after fast-track unicompartmental knee arthroplasty - A prospective multicentre cohort study of 3927 procedures.

INTRODUCTION: Unicompartmental knee arthroplasty (UKA) has increased due to potential favourable complication rates when compared to total knee arthroplasty (TKA). Although venous thromboembolism (VTE) is a well-documented complication after TKA limited data is available after UKA and mostly presented as secondary findings in observational comparisons to TKA. There is a lack of fast-track UKA VTE studies and no guidelines on thromboprophylaxis. Consequently, we described the 90-day incidence of VTE after UKA within a multicentre fast-track collaboration. MATERIALS AND METHODS: We used an observational cohort study design from 8 dedicated fast-track centres with prospective collection of preoperative risk-factors, complete follow-up on length of stay (LOS), 90-day readmissions and mortality from the Danish National Patient Registry and analysis of health records if LOS > 2 days or an ICD-10 code of VTE. Due to limited events we refrained from analysis of independent risk-factors. RESULTS: In 3927 procedures (46.1% males, mean age 66.2 (SD 9.4) years) median LOS was 1 [IQR 0-1] day and 7.5% had LOS > 2 days. The 90-day incidence of VTE was 16 (0.41%) and 14 (0.37%) when excluding preoperatively anticoagulated patients. There were 5 (0.13%) pulmonary embolisms and 11 (0.28%) deep-vein thrombosis after median 18 [11.75-35.25] days. 90-day mortality was 3 (0.08%) with no fatal PE or initial postoperative VTE. CONCLUSIONS: The 90-day incidence of VTE after fast-track UKA was 0.41% (0.37% when excluding preoperatively anticoagulated patients), which is comparable to reports of 0.39% VTEs after fast-track TKA in the same departments. Investigations on risk-factors are needed for optimizing thromboprophylaxis.

Postoperative 30-day complications after cemented/hybrid versus cementless total hip arthroplasty in osteoarthritis patients > 70 years.

Background and purpose - The use of cementless total hip arthroplasty (THA) in elderly patients is debated because of increased risk of early periprosthetic femoral fractures. However, cemented femoral components carry a risk of bone cement implantation syndrome. Hence, we compared in-hospital complications, complications leading to readmission and mortality ≤ 30 days postoperatively between hybrid/cemented (cemented femoral component) vs. cementless THA in osteoarthritis patients > 70 years.Patients and methods - This is a prospective observational cohort study in 9 centers from January 2010 to August 2017. We used 30-day follow-up from the Danish National Patient Registry, patient records, and data from the Danish Hip Arthroplasty Register. Only THAs performed as a result of osteoarthritis were included.Results - 3,368 (42%) of the THAs were cemented/hybrid and 4,728 (58%) cementless. The in-hospital complication risk was 7.7% after cemented/hybrid vs. 5.3% after cementless THA (< 0.001), statistically not significant when adjusting for comorbidities (p = 0.1). There were similar risks of complications causing readmission (5.7% vs. 6.2%) and mortality ≤ 30 days (0.2% vs. 0.3%). 15 cases (0.4%) of pulmonary embolism (PE) were found after cemented/hybrid vs. 4 (0.1%) after cementless THA (p = 0.001); none occurred within 24 hours postoperatively. 2 of the PEs after cementless THA led to mortality. Cemented/hybrid THA remained significantly associated with risk of PE (RR 3.9, p = 0.02), when adjusting for comorbidities. BMI > 35 was associated with highest risk of PE (RR 5.7, p = 0.003). The risk of periprosthetic femoral fracture was 0.2% after cemented/hybrid vs. 1.5% after cementless THA (p < 0.001) and the risk of dislocations was 1.2% after cemented/hybrid THA vs. 1.8% after cementless THA (p = 0.04).Interpretation - The higher risk of PE after cemented/hybrid THA and higher risk of periprosthetic femoral fractures and dislocations after cementless THA highlights that both medically and surgically complications are related to fixation technique and have to be considered.

Fast-track hip and knee arthroplasty in older adults-a prospective cohort of 1,427 procedures in patients ≥85 years.

INTRODUCTION: fast-track protocols in total hip and knee arthroplasty (THA/TKA) have improved postoperative recovery and reduced postoperative morbidity. Additionally, increasing life expectancy and improved surgical techniques have led to an increasing number of older adult patients undergoing THA/TKA. However, no large detailed studies on fast-track THA/TKA in older adults are available. Consequently, we aimed to describe the length of stay (LOS) and postoperative morbidity in a large cohort of patients ≥85 years within a continuous multicentre fast-track collaboration. METHODS: we used a prospective observational cohort design with unselected consecutive data between 2010 and 2017 on primary elective THA and TKA patients ≥85 years. Data were obtained from nine centres reporting to the Lundbeck Foundation Centre for Fast-track Hip and Knee Replacement database and the Danish National Patient Registry on LOS, readmissions and mortality. Causes of morbidity were determined by review of health records. RESULTS: we included 1,427 (3.9% of all THA/TKA) procedures with 62.3% THA. Median age was 87 (IQR: 85-88) years with 71% women. LOS decreased from median 4 (3-6) days in 2010 to 2 (2-3) days in 2017. The proportion with LOS > 4 days decreased from 32 to 18%. Readmission and mortality rate remained at about 11.7 and 0.9% after 30 days and 16.0 and 1.5% after 90 days, respectively. CONCLUSION: this detailed large multicentre fast-track THA/TKA study in patients ≥85 years found major reductions in LOS without increase in readmission or mortality rates. The unchanged readmission rate poses an area for further improvements.

Venous Thromboembolism despite Ongoing Prophylaxis after Fast-Track Hip and Knee Arthroplasty: A Prospective Multicenter Study of 34,397 Procedures.

INTRODUCTION: Venous thromboembolism (VTE) is a serious complication to total hip and knee arthroplasty (THA/TKA). However, recent publications found low 90-day incidences of VTE with in-hospital only thromboprophylaxis after fast-track THA and TKA, but with a subgroup with VTE despite thromboprophylaxis. OBJECTIVES: We aimed to investigate in detail the incidence and risk for VTE despite ongoing thromboprophylaxis after fast-track THA and TKA. MATERIALS AND METHODS: This is a prospective unselected multicenter cohort from January 2010 to August 2017. Data on preoperative characteristics were entered into the Lundbeck Foundation Centre for Fast-track Hip and Knee Replacement database (www.FTHK.dk). Length of stay (LOS) and complete 90-day follow-up was obtained from the Danish National Patient Registry and review of medical records. Patients with preoperative use of potent anticoagulants were excluded. RESULTS: Of 34,397 procedures, 32 (0.09%, 22.4% of all VTE) had VTE after median 2 (interquartile range: 2-4) days despite ongoing thromboprophylaxis. Twenty-nine (2.1% of LOS > 5 days) occurred with LOS > 5 days and 3 during primary admission with LOS ≤ 5 days. Note that 78% of VTEs despite ongoing thromboprophylaxis occurred without any identifiable pre-VTE complication. Risk factors were age from 81 to 85 years (odds ratio [OR] 6.3 [95% confidence interval: 1.8-22.4], p = 0.005), body mass index (BMI) < 18.5 (OR 11.1 [1.1-109.2], p = 0.040), BMI 35 to 40 (OR 5.1 [1.0-26.2], p = 0.050), and BMI ≥ 40 (OR 21.8 [4.6-103.6], p < 0.001). CONCLUSION: VTE after fast-track THA/TKA occurred after median 2 days in 0.09% (22% of all VTE) despite ongoing thromboprophylaxis. Further investigation of this "high-risk" population might help to improve the optimal choice for patient-specific thromboprophylaxis to further reduce incidence of postoperative VTE.

Temporal trends in length of stay and readmissions after fast-track hip and knee arthroplasty.

INTRODUCTION: Implementation of fast-track protocols in total hip and knee arthroplasty (THA/TKA) has dramatically changed the perioperative care, leading to a subsequent reduction in post-operative length of stay (LOS) and mor-bidity. Previous investigations in Denmark have shown a reduction in LOS from about ten days in 2000 to four days in 2009. We aimed to describe temporal changes in LOS and readmissions within the context of a continuous multicentre collaboration focusing on enhancing recovery and reducing morbidity after fast-track THA and TKA. METHODS: We used an observational cohort design from nine Danish orthopaedic centres. All procedures were performed from January 2010 to August 2017. Data on LOS and 90-day readmissions were obtained from The Danish National Patient Registry. Cause of readmission and possible association with surgery were investigated using discharge summaries or health records. RESULTS: We included 36,608 procedures with a median age of 69 (range: 62-75) years of whom 58% were women. LOS decreased from a median of three (range: 2-3) days in 2010 to one (range: 1-2) days in 2017. The proportion of patients with LOS > 4 days decreased from 9.6% to 4.4%. Still, 90-day readmissions remained stable throughout the period at ≈ 8%. CONCLUSIONS: A reduction in both LOS and proportion of patients with prolonged LOS without an increase in readmission is possible within a multicentre collaboration aiming at enhancing recovery and reducing morbidity. FUNDING: The study was supported by an unconditional PhD grant from Lundbeckfonden to PBP (R230-2017-166). TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov (NCT01515670).

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.

Safety of In-Hospital Only Thromboprophylaxis after Fast-Track Total Hip and Knee Arthroplasty: A Prospective Follow-Up Study in 17,582 Procedures.

Most international guidelines recommend pharmacological thromboprophylaxis after total hip and knee arthroplasty (THA/TKA) for 10 to 35 days. However, a recent cohort study on fast-track THA and TKA questioned the need for prolonged thromboprophylaxis when length of stay (LOS) is ≤ 5 days. We aimed at re-investigating the incidence of venous thromboembolism (VTE) in fast-track THA and TKA with in-hospital only thromboprophylaxis when LOS was ≤ 5 days. Prospective cohort study from 1 December 2011 to 30 October 2015 on elective unilateral THA/TKA with in-hospital only thromboprophylaxis if LOS was ≤ 5 days. Prospective information on co-morbidity and complete 90-day follow-up through the Danish National Patient Registry and medical records. Patients with pre-operative use of anticoagulants were excluded. In per protocol analysis, 17,582 (95.5%) had LOS of ≤ 5 days (median, 2 [interquartile range, 2-3]) and in-hospital thromboprophylaxis only. Incidence of symptomatic VTE was 0.40%, consisting of 28 (0.16%) pulmonary embolisms (PEs), 38 (0.22%) deep vein thrombosis (DVT) and 4 (0.02%) combined DVT and PE. Two PEs (0.01%) were fatal. VTE-associated risk factors with in-hospital only thromboprophylaxis were age > 85 years, odds ratio (OR) of 3.74 (95% confidence interval: 1.15-12.14, p = 0.028), body mass index (BMI) of 35 to 40, OR of 2.55 (1.02-6.35, p = 0.045) and BMI > 40, OR of 3.28 (1.02-10.56, p = 0.046). In conclusion, 90-day incidence of VTE after fast-track THA and TKA with in-hospital thromboprophylaxis only was 0.40%. Prolonged thromboprophylaxis may be reserved for LOS > 5 days or specific high-risk patients, but requires further studies regarding optimal type and duration of thromboprophylaxis.