Is Preoperative Weight Reduction in Patients Who Have Body Mass Index ≥ 40 Associated With Lower Complication Rates After Primary Total Hip Arthroplasty?

BACKGROUND: Given the heightened risk of postoperative complications associated with obesity, delaying total hip arthroplasty (THA) in patients who have a body mass index (BMI) > 40 to maximize preoperative weight loss has been advocated by professional societies and orthopaedic surgeons. While the benefits of this strategy are not well-understood, previous studies have suggested that a 5% reduction in weight or BMI may be associated with reduced complications after THA. METHODS: We identified 613 patients who underwent primary THA in a single institution during a 7-year period and who had a BMI >40 recorded from 9 to 12 months prior to surgery. Subjects were stratified into 3 cohorts based on whether their baseline BMI decreased by >5% (147 patients, 24%), was unchanged ( ± 5%) (336 patients, 55%), or increased by >5% (130 patients, 21%) on the day of surgery. The frequency of 90-days Hip Society and Centers for Medicare & Medicaid Services complications was compared between these cohorts. There were significant baseline differences between the cohorts with respect to baseline American Society of Anesthesiologists class (P < .001) and hemoglobin A1C (P = .011), which were accounted for in a multivariate regression analysis. RESULTS: In univariate analysis, there was a lower incidence of readmission (P = .025) and total complications (P = .005) in the increased BMI cohort. The overall complication rate was 18.4% in the decreased BMI cohort, 17.6% in the unchanged cohort, and 6.2% in the increased cohort. However, multivariable regression analysis controlling for potential confounders did not find that preoperative change in BMI was associated with differences in 90-days complications between cohorts (P > .05). CONCLUSIONS: Patients who have a BMI >40 and achieved a clinically significant (>5%) BMI reduction prior to THA did not have a lower risk of 90-days complications or readmissions. Thus, delaying THA in these patients to encourage weight loss may result in restricting access to a beneficial surgery without an appreciable safety benefit.

Body morphometry did not affect the accuracy of a second-generation, miniature imageless navigation system for total hip arthroplasty (THA) using a posterior approach.

Introduction: Some modern imageless navigation platforms for total hip arthroplasty (THA) rely on virtual frontal and sagittal planes determined with the patient in the lateral decubitus position. Body morphometry that changes with gender, body mass index, and other demographic factors may affect accuracy in patient positioning and consequently, navigation accuracy. The objective of this study was to analyze the influence of patient factors on the intraoperative accuracy of a second-generation imageless computer-assisted surgery platform. Methods: 325 consecutive patients undergoing posterior approach, navigated THA arthroplasty for primary osteoarthritis by a single surgeon were retrospectively reviewed. An optic-based imageless navigation system referenced off a generic sagittal and coronal plane was used to determine acetabular inclination and anteversion. Acetabular accuracy was determined by assessing differences between intraoperative values and those obtained from measuring standardized 6-week follow-up radiographs. The effect of age, gender, BMI, race, ethnicity, and laterality on acetabular accuracy was assessed via t-tests, Pearson correlation and ANOVA. Results: Gender had a significant impact on raw inclination accuracy (females and males had an average error of 1.41° and -1.03°, respectively - p < 0.001). There was a weak correlation between acetabular accuracy and patient age and BMI as a continuous variable (both absolute γ < 0.2). No difference was found between acetabular accuracy and BMI groups. Conclusion: This second-generation imageless computer assisted device provided accurate cup positioning regardless of patient's BMI. Gender was the only factor impacting inclination accuracy.

Substantial Weight Loss May Not Improve Early Outcomes of Total Knee Arthroplasty in the Morbidly Obese.

BACKGROUND: Body mass index (BMI) cutoffs for morbidly obese patients otherwise indicated for total knee arthroplasty (TKA) have been widely proposed and implemented, though they remain controversial. Previous studies suggested that a 5% reduction in BMI may be associated with fewer postoperative complications. Thus, the purpose of this study was to determine whether a substantial reduction in preoperative BMI in morbidly obese patients improved 90-day outcomes after TKA. METHODS: There were 1,270 patients who underwent primary TKA at a single institution and had a BMI > 40 recorded during the year prior to surgery. Patients were stratified into three cohorts based on whether their BMI within 3 months to 1 year preoperatively had decreased by ≥ 5% (228 patients [18%]); increased by ≥ 5% (310 [24%]); or remained unchanged (within 5%) (732 [58%]) on the day of surgery. There were several baseline differences between the cohorts with respect to medical comorbidities. The rate of 90-day complications and six-week patient-reported outcome measures were compared via univariate and multivariable analyses. RESULTS: On univariate analysis, individual and total complication rates were similar between the cohorts (P > .05). On multivariable logistic regression, the risk of complications was similar in patients who had decreased versus unchanged BMI (OR [odds ratio] 1.0; P = .898). However, there was a higher risk of complications in the increased BMI cohort compared to those patients who had an unchanged BMI (OR 1.5; P = .039). The six-week patient-reported outcome measures were similar between the cohorts. CONCLUSIONS: Patients who have a BMI > 40 who achieved a meaningful reduction in BMI prior to TKA did not have a lower rate of 90-day complications than those whose BMI remained unchanged. Furthermore, considering that nearly one in four patients experienced a significant increase in BMI while awaiting surgery, postponing TKA may actually be detrimental.

Obesity Severity Does Not Associate With Rate, Timing, or Invasiveness of Early Reinterventions After Total Knee Arthroplasty.

BACKGROUND: The use of body mass index (BMI) cutoff values has been suggested for proceeding with total knee arthroplasty (TKA) in obese patients. However, the relationship between obesity severity and early reoperations after TKA is poorly defined. This study evaluated whether increased World Health Organization (WHO) obesity class was associated with risk, severity, and timing of reintervention within one year after TKA. METHODS: There were 8,674 patients from our institution who had a BMI ≥ 30 and underwent unilateral TKA for primary osteoarthritis between 2016 and 2021. Patients were grouped by WHO obesity class: 4,456 class I (51.5%), 2,527 class II (29.2%), and 1,677 class III (19.4%). A chart review was performed to determine patient characteristics and identify patients who underwent any closed or open reintervention requiring anesthesia within the first postoperative year. Regression analyses were performed to identify variables associated with increased odds ratios (ORs) for requiring a reintervention, its timing, and invasiveness. RESULTS: There were 158 patients (1.8%) who required at least one reintervention, and 15 patients (0.2%) required at least 2 reinterventions. Reintervention rates for obesity classes I, II, and III were 1.8% (n = 81), 2.0% (n = 51), and 1.4% (n = 23), respectively. There were 65 closed procedures (41.1%), 47 minor procedures (29.7%), 34 open with or without liner exchange (21.5%), and 12 revisions with component exchange (7.6%). Obesity class was not associated with reintervention rate (P = .3), timing (P = .36), or invasiveness (P = .93). Diabetes (odds ratio [OR] = 2.47; P = .008) was associated with a need for reintervention. Non-Caucasian race (OR = 1.7; P = .01) and Charlson comorbidity index (OR = 2.1; P = .008) were associated with earlier reintervention. No factors were associated with the invasiveness of reintervention. CONCLUSIONS: The WHO obesity class did not associate with rate, timing, or invasiveness of reintervention after TKA in obese patients. These findings suggest that policies that restrict the indication for elective TKA based only on a BMI limit have limited efficacy in reducing early reintervention after TKA in obese patients. LEVEL OF EVIDENCE: III.

Contemporary Isolated Bearing Exchange for the Management of Hip Instability Following Primary Total Hip Arthroplasty.

BACKGROUND: Isolated ball and liner exchanges (IBLEs) can be performed to increase hip joint stability, but historical results have been mixed due to a lack of head size options or dual mobility articulations. The purpose of this study was to evaluate the contemporary results of IBLEs in patients who have instability following primary total hip arthroplasty (THA). METHODS: We retrospectively reviewed 65 primary THAs from 2016 to 2020 with hip instability undergoing IBLE or conversion to dual mobility articulation. There were 31 men and 34 women who had an average age of 70 years (range, 26 to 92). The mean time to revision from primary was 40.1 months (range, 1 to 120). In 52 cases, IBLE was performed using conventional bearings, while 13 hips were converted to dual mobility. Radiographic factors, including acetabular component orientation, reproduction of hip joint offset, leg lengths, and outcomes such as recurrent instability requiring subsequent revision and patient-reported outcome measure, were recorded and compared. RESULTS: There were 12 (18.4%) hips that experienced subsequent instability and required another revision (17.3% ball and liner exchange versus 23.1% dual mobility articulation, P = .615). The mean time to rerevision for instability was 17.1 months. There were no significant differences in either acetabular component anteversion (P = .25) or restoration of hip joint offset (P = .87) in patients who required another revision for instability compared to those who did not, respectively. At 1 year, patients undergoing conventional bearing exchange reported higher Hip Dysfunction Osteoarthritis Outcome Score for Joint Replacements (P = .002) and Veterans Rand physical component (P = .023) scores compared to those who underwent a conversion to dual mobility articulation. Only age > 75 years at the time of surgery was associated with increased risk for dislocation (odds ratio 7.2, confidence interval 1.2 to 43.7, P = .032). CONCLUSIONS: Isolated bearing exchanges for instability following THA remained at high risk for subsequent instability. Conversion to dual mobility articulations did not reduce the risk of reoperation.

The John N. Insall Award: Does Melatonin Improve Subjective Sleep Quality After Total Knee Arthroplasty? A Randomized, Placebo-Controlled Trial.

BACKGROUND: Sleep disturbance is a common problem following total knee arthroplasty (TKA). The objective of this study was to determine if exogenous melatonin improves sleep quality following primary TKA. METHODS: A randomized, double-blind, placebo-controlled trial was conducted. A total of 172 patients undergoing unilateral TKA for primary knee osteoarthritis were randomized to receive either 5 mg melatonin (n = 86) or 125 mg vitamin C placebo (n = 86) nightly for 6 weeks. The primary outcome was the Pittsburgh Sleep Quality Index (PSQI) at 6 weeks and 90 days postoperatively. Secondary outcomes included 6-week and 90-day patient-reported outcome measures (PROMs), morphine milligram equivalents prescribed, medication compliance, adverse events, and 90-day readmissions. RESULTS: Mean PSQI scores worsened at 6 weeks before returning to the preoperative baseline at 90 days in both groups. There were no differences in PSQI scores between melatonin and placebo groups at 6 weeks (10.2 ± 4.2 versus 10.5 ± 4.4, P = .66) or 90 days (8.1 ± 4.1 versus 7.5 ± 4.0, P = .43). Melatonin did not improve the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Lower Extremity Activity Scale, Visual Analog Scale for pain, or Veterans Rand 12 Physical Component Score or Mental Component Score at 6 weeks or 90 days. Poor sleep quality was associated with worse PROMs at 6 weeks and 90 days on univariate and multivariable analyses, but melatonin did not modify these associations. There were no differences in morphine milligram equivalents prescribed, medication compliances, adverse events, or 90-day readmissions between both groups. CONCLUSIONS: Exogenous melatonin did not improve subjective sleep quality or PROMs at 6 weeks or 90 days following TKA. Poor sleep quality was associated with worse patient-reported function and pain. Our results do not support the routine use of melatonin after TKA.

Risk factors for blood transfusion and postoperative anaemia following total knee arthroplasty.

Aims: Blood transfusion and postoperative anaemia are complications of total knee arthroplasty (TKA) that are associated with substantial healthcare costs, morbidity, and mortality. There are few data from large datasets on the risk factors for these complications. Methods: We retrospectively reviewed the records of TKA patients from a single tertiary care institution from February 2016 to December 2020. There were a total of 14,901 patients in this cohort with a mean age of 67.9 years (SD 9.2), and 5,575 patients (37.4%) were male. Outcomes included perioperative blood transfusion and postoperative anaemia, defined a priori as haemoglobin level < 10 g/dl measured on the first day postoperatively. In order to establish a preoperative haemoglobin cutoff, we investigated a preoperative haemoglobin level that would limit transfusion likelihood to ≤ 1% (13 g/dl) and postoperative anaemia likelihood to 4.1%. Risk factors were assessed through multivariable Poisson regression modelling with robust error variance. Results: In multivariable analyses, each gram of tranexamic acid reduced transfusion likelihood by 39% (adjusted risk ratio (ARR) 0.61 (95% confidence interval (CI) 0.47 to 0.78)). Risk factors associated with an increased risk of transfusion included operating time (ARR 2.07 (95% CI 1.54 to 2.77)) and drain use (ARR 1.73 (95% CI 1.34 to 2.24)). Conclusion: In this study, we found that increased tranexamic acid dosing, decreased operating time, and decreased drain use may reduce transfusions following TKA. We also established a single preoperative haemoglobin cutoff of 13 g/dl that could help minimize transfusions and reduce postoperative complete blood counts.

The Risk Assessment and Prediction Tool (RAPT) Score Predicts Discharge Destination, Length of Stay, and Postoperative Mobility After Total Joint Arthroplasty.

BACKGROUND: Predicting an arthroplasty patient's discharge disposition, length of stay (LOS), and physical function is helpful because it allows for preoperative patient optimization, expectation management, and discharge planning. The goal of this study was to evaluate the ability of the Risk Assessment and Prediction Tool (RAPT) score to predict discharge destination, LOS, and postoperative mobility in patients undergoing primary total knee arthroplasty (TKA) and total hip arthroplasty (THA). METHODS: Primary unilateral TKAs (n = 9,064) and THAs (n = 8,649) performed for primary osteoarthritis at our institution from 2018 to 2021 (excluding March to June 2020) were identified using a prospectively maintained institutional registry. We evaluated the associations between preoperative RAPT score and (1) discharge destination, (2) LOS, and postoperative mobility as measured by (3) successful ambulation on the day of surgery and (4) Activity Measure for Post-Acute Care (AM-PAC) "6-Clicks" score. RESULTS: On multivariable analyses adjusting for multiple covariates, every one-point increase in RAPT score among TKA patients was associated with a 1.82-fold increased odds of home discharge (P < .001), 0.22 days shorter LOS (P < .001), 1.13-fold increased odds of ambulating on postoperative day 0 (P < .001), and 0.25-point higher Activity Measure for Post-Acute Care score (P < .001). Similar findings were seen among THAs. A RAPT score of 8 or higher was the most sensitive and specific cutoff to predict home discharge. CONCLUSION: Among nearly 18,000 TKA and THA patients, RAPT score was predictive of discharge disposition, LOS, and postoperative mobility. A RAPT score of 8 or higher was the most sensitive and specific cutoff to predict discharge to home. In contrast to prior studies of the RAPT score which have grouped TKAs and THAs together, this study ran separate analyses for TKAs and THAs and found that THA patients seemed to perform better than TKA patients with equal RAPT scores, suggesting that RAPT may behave differently between TKAs and THAs, particularly in the intermediate risk RAPT range.

A single-center, open-label, randomized, parallel-group trial to pilot the effectiveness of a peer coach behavioral intervention versus an active control in reducing anxiety and depression in patients scheduled for total knee replacement.

BACKGROUND: Moving Well is a behavioral intervention for patients with knee osteoarthritis (KOA) scheduled for a total knee replacement (TKR). The objective of this intervention is to help patients with KOA mentally and physically prepare for and recover from TKR. METHODS: This is an open-label pilot randomized clinical trial that will test the feasibility and effectiveness of the Moving Well intervention compared to an attention control group, Staying Well, to reduce symptoms of anxiety and depression in patients with KOA undergoing TKR. The Moving Well intervention is guided by Social Cognitive Theory. During this 12-week intervention, participants will receive 7 weekly calls before surgery and 5 weekly calls after surgery from a peer coach. During these calls, participants will be coached to use principles of cognitive behavioral therapy (CBT), stress reduction techniques, and will be assigned an online exercise program, and self-monitoring activities to complete on their own time throughout the program. Staying Well participants will receive weekly calls of similar duration from research staff to discuss a variety of health topics unrelated to TKR, CBT, or exercise. The primary outcome is the difference in levels of anxiety and/or depression between participants in the Moving Well and Staying Well groups 6 months after TKR. DISCUSSION: This study will pilot test the feasibility and effectiveness of Moving Well, a peer coach intervention, alongside principles of CBT and home exercise, to help patients with KOA mentally and physically prepare for and recover from TKR. TRIAL REGISTRATION: Clinicaltrials.gov. NCT05217420; Registered: January 31, 2022.

Patients Undergoing Primary, Cementless TKA had Similar Pain, Opioid Utilization, and Functional Outcomes Compared to Matched Patients With Cemented Fixation.

BACKGROUND: Despite renewed interest in cementless fixation of total knee implants, many surgeons have anecdotal concerns about slower recovery and higher early pain scores. We sought to analyze 90-day opioid utilizations, inhospital pain scores, and patient-reported outcome measures (PROMs) in patients undergoing primary cemented versus cementless total knee arthroplasty (TKA). METHODS: We retrospectively identified a cohort of opioid naïve patients undergoing primary TKA for osteoarthritis. There were 186 patients who had cementless TKAs matched 1:6 with 1,116 who received a cemented TKAs based on age (±6 years), body mass index (BMI) (±5), and sex. We compared inhospital pain scores, 90-day opioid utilizations in morphine milligram equivalents (MMEs), and early postoperative PROMs. RESULTS: The cemented and cementless cohorts had similar lowest (0.09 versus 0.08), highest (7.36 versus 7.34), and average (3.26 versus 3.27) pain scores using numeric rating scale (P > .05). They received similar inhospital (90 versus 102, P = .176), discharge (315 versus 315, P = .483), and total (687 versus 720, P = .547) MMEs. They had similar average inpatient hourly opioid consumption (2.5 versus 2.5 MMEs/hour, P = .965). Average refills 90 days postoperatively were similar in both cohorts (1.5 versus 1.4 refills, P = .893). Also, preoperative, 6-week, 3-month, delta 6-week, and delta 3-month PROMs scores were similar between cemented and cementless cohorts (P > .05) CONCLUSION: This matched study demonstrated similar in-hospital pain scores and opioid utilization, total MMEs prescribed within 90 days, and PROMs at 6 weeks and 3 months postoperatively between cemented and cementless TKAs. LEVEL OF EVIDENCE: III, retrospective cohort study.

Wound Complications Are Affected by Different Skin Closure Methods in Primary Hip and Knee Arthroplasty.

BACKGROUND: There is a lack of consensus on optimal skin closure and dressing strategies to reduce early wound complication rates after primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: All 13,271 patients at low risk for wound complications undergoing primary, unilateral THA (7,816), and TKA (5,455) for idiopathic osteoarthritis at our institution between August 2016 and July 2021 were identified. Skin closure, dressing type, and postoperative events related to wound complications were recorded during the first 30 postoperative days. RESULTS: The need for unscheduled office visits to address wound complications was more frequent after TKA than THA (2.74 versus 1.78%, P < .001), and after direct anterior versus posterior approach THA (2.94 versus 1.39%, P < .001). Patients who developed a wound complication, had a mean of 2.9 additional office visits. Compared to the use of topical adhesives, skin closure with staples had the highest risk of wound complications (odds ratio 1.8 [1.07-3.11], P = .028). Topical adhesives with polyester mesh had higher rates of allergic contact dermatitis than topical adhesives without mesh (1.4 versus 0.5%, P < .0001). CONCLUSION: Wound complications after primary THA and TKA were often self-limited but increased burden on the patient, surgeon, and care team. These data, which suggest different rates of certain complications with different skin closure strategies, can inform a surgeon on optimal closure methods in their practice. Adoption of the skin closure technique with the lowest risk of complications in our hospital would conservatively result in a reduction of 95 unscheduled office visits and save a projected $585,678 annually.

Early perioperative magnetic resonance findings in patients with foot drop following total hip Arthroplasty: A descriptive case-series.

PURPOSE: This study aims to characterize iatrogenic sciatic nerve injury patterns in the early, perioperative period following posterior-approach total hip arthroplasty (THA) with magnetic resonance imaging (MRI). METHODS: This was an IRB-approved retrospective analysis of patients acquired from a longitudinal, single site radiology database of patients who underwent MRI for "foot drop" within 4 weeks following posterior-approach THA surgery, over a 20-year period. RESULTS: MRI exams from 51 patients (mean age 62 years; 32 females) who met inclusion criteria were evaluated. Mean time to MRI was 2.4 days. Of 51 patients, 43 underwent primary THA, 6 revision THA and 2 explantation with antibiotic spacer placement. Ten exams revealed a normal appearance of the sciatic nerve. Nineteen showed compression of the sciatic nerve by edema or a fluid collection, without intrinsic nerve abnormality. Fifteen demonstrated perineural tethering or scar/granulation tissue encasement of the nerve, and in half of these cases the sciatic nerve was enlarged and/or hyperintense on fluid-sensitive sequences. Six patients had sciatic nerve compression secondary to quadratus femoris retraction. Six patients had complete resolution of the foot drop at a mean follow-up of 37.3 months following surgery, and in these cases the sciatic nerve appeared normal on the initial postoperative MRI. Remaining patients all had persistent weakness and paresthesias in the sciatic nerve distribution at a mean follow-up duration of 34.3 months. CONCLUSION: This retrospective case series demonstrates various sciatic nerve injury patterns in the early perioperative period on MRI and proposes a targeted MRI protocol to evaluate the sciatic nerve post THA surgery.

History of COVID-19 infection is not associated with increased D-dimer levels and risk of deep-vein thrombosis in total joint arthroplasty.

INTRODUCTION: In the acute phase of COVID-19, elevated D-dimer levels indicate a hypercoagulable state putting the patients at increased risk for venous thromboembolic disease (VTE). It is unclear, if prior COVID-19 disease increases the risk for VTE after total joint arthroplasty (TJA) and if D-dimer levels can be used to identify patients at risk. MATERIALS AND METHODS: D-Dimer levels of 313 consecutive SARS-CoV-2 IgG-positive and 2,053 -negative patients undergoing TJA between 05/20 and 12/20 were evaluated. D-Dimer levels were divided into three groups: < 200 ng/ml, 200-400 ng/ml, and > 400 ng/ml D-dimer units (DDU). 277 SARS-CoV-2 IgG-positive patients underwent a Doppler ultrasound to rule out deep-vein thrombosis (DVT) 4-6 weeks after TJA. RESULTS: D-Dimer levels did not differ significantly between SARS-CoV-2 IgG-positive and -negative patients (p value 0.53). Among SARS-CoV-2 IgG-negative patients, 1687 (82.17%) had D-dimer levels < 200 ng/ml, 256 (12.47%) between 200 and 400 ng/ml, and 110 (5.36%) > 400 ng/ml. Of the SARS-CoV-2 IgG-positive patients, 257 (83.71%) had D-dimer levels < 200 ng/ml, 34 (11.07%) between 200 and 400 ng/ml, and 16 (5.21%) > 400 ng/ml. A postoperative DVT was detected in nine patients (2.9%) in the SARS-CoV-2 IgG-positive group and a PE in one patient (0.3%). 7/229 patients with < 200 ng/ml (3.1%), 1/28 patients (3.6%) with 200-400 ng/ml and 1/9 patients (11.1%) with D-dimer levels > 400 ng/ml had a DVT or PE (p = 0.43). CONCLUSIONS: The findings of this investigation suggest there is no difference in D-dimer levels between SARS-CoV-2 IgG-positive and -negative patients undergoing TJA. Although there is a trend for increased VTE rates with increased D-dimer levels, routine D-dimer testing is not recommended based on the current data. SARS-CoV-2 IgG-positive patients have a low risk of VTE in the current study.

Use of a novel imageless navigation system reduced fluoroscopy exposure and improved acetabular positioning in anterior approach total hip arthroplasty: a case-control study.

INTRODUCTION: Direct anterior approach (DAA) for total hip arthroplasty (THA) frequently utilizes fluoroscopy. The purpose of this study is to assess the impact of using a novel, imageless THA navigation system on radiation exposure and acetabular cup placement consistency. MATERIALS AND METHODS: This was a retrospective, single-surgeon cohort study of a consecutive group of patients who underwent DAA THA for osteoarthritis. An optic-based imageless navigation system was used to determine intraoperative acetabular inclination and anteversion angles referenced off of a generic coronal and sagittal plane in 71 cases (study group). These were compared with 71 manual cases (control group) for fluoroscopy exposure, operative duration, and acetabular placement variation. Cohorts were similar in their distributions of sex, race, ethnicity, and body mass index. Comparisons between groups were made using independent samples t tests. Alpha error was 0.05. RESULTS: Study patients experienced significantly less fluoroscopy exposure time {3.59 [Standard Deviation (SD) 1.95] vs. 9.15 (SD 5.98) seconds; p < 0.001} and dosage (0.30 [SD 0.23] vs. 0.78 [SD 0.63] mGy; p < 0.001). Study and control patients had similar operative times [82.69 (SD 11.70) vs. 89.54 (SD 14.60) minutes; p = 0.09]. The study group had a significantly lower radiographic variation for inclination and anteversion, based on mean proximity to the centroid of each cohort [3.55 (SD 1.88) vs. 5.39 (SD 3.51); p < 0.001] and also a greater proportion of cases that fell within 1 SD of the mean cohort inclination and anteversion (40.8% vs. 21.1%; p = 0.009). CONCLUSIONS: Use of a novel imageless navigation system for DAA THA significantly reduced fluoroscopic radiation exposure and improved consistency in acetabular cup placement.

Effectiveness of oral versus intravenous tranexamic acid in primary total hip and knee arthroplasty: a randomised, non-inferiority trial.

BACKGROUND: Tranexamic acid (TXA) reduces rates of blood transfusion for total hip arthroplasty (THA) and total knee arthroplasty (TKA). Although the use of oral TXA rather than intravenous (i.v.) TXA might improve safety and reduce cost, it is not clear whether oral administration is as effective. METHODS: This noninferiority trial randomly assigned consecutive patients undergoing primary THA or TKA under neuraxial anaesthesia to either one preoperative dose of oral TXA or one preoperative dose of i.v. TXA. The primary outcome was calculated blood loss on postoperative day 1. Secondary outcomes were transfusions and complications within 30 days of surgery. RESULTS: Four hundred participants were randomised (200 THA and 200 TKA). The final analysis included 196 THA patients (98 oral, 98 i.v.) and 191 TKA patients (93 oral, 98 i.v.). Oral TXA was non-inferior to i.v. TXA in terms of calculated blood loss for both THA (effect size=-18.2 ml; 95% confidence interval [CI], -113 to 76.3; P<0.001) and TKA (effect size=-79.7 ml; 95% CI, -178.9 to 19.6; P<0.001). One patient in the i.v. TXA group received a postoperative transfusion. Complication rates were similar between the two groups (5/191 [2.6%] oral vs 5/196 [2.6%] i.v.; P=1.00). CONCLUSIONS: Oral TXA can be administered in the preoperative setting before THA or TKA and performs similarly to i.v. TXA with respect to blood loss and transfusion rates. Switching from i.v. to oral TXA in this setting has the potential to improve patient safety and decrease costs.

Reasons and Risk Factors for Failed Same-Day Discharge After Primary Total Knee Arthroplasty.

BACKGROUND: As ambulatory total knee arthroplasty (TKA) becomes increasingly common, unplanned admission after surgery presents a challenge for the health care system. Studies evaluating the reasons and risk factors for this occurrence are limited. We sought to evaluate the reasons for unplanned admission after surgery and identify risk factors associated with this occurrence. METHODS: Patients registered in an institutional ambulatory joint arthroplasty program who underwent a TKA from 2017-2020 were retrospectively reviewed. The criteria for enrollment include candidates for unilateral TKA between the ages of 18 and 70 years, with a body mass index (BMI) of less than 35, and appropriate social and material support at home. Patients who had certain comorbidities including coronary artery disease, valvular heart disease, and opioid dependence were not eligible. A total of 274 patients who underwent TKA with planned same-day discharge (SDD) were identified in the medical record and reviewed. In this cohort, 140 patients (51.1%) were discharged on the day of surgery and 134 patients (48.9%) required a minimum 1-night admission. Demographics, comorbidities, and perioperative data were collected. Factors associated with failed SDD were identified using multivariate logistic regression. RESULTS: The most common reasons for failed SDD were failure to meet ambulation goals (25%) and logistical issues related to a late-day case (19%). Risk factors for failed SDD include general anesthesia (odds ratio (OR) 12.60, P = .047), procedure start time after 11:00 am (OR 5.16, P < .001), highest postoperative pain score >8 (visual analogue scale, OR 5.78, P = .001). Willingness to accept a higher pain threshold before discharge (visual analogue scale 4 to 10) was associated with successful SDD (OR 3.0, P < .001). Age and American Society of Anesthesiologists (ASA) classification were not associated with failed SDD. CONCLUSIONS: The most common reasons for failed SDD were related to logistical issues and postoperative mobilization. Risk factors for failed SDD involve case timing and pain control. Modifiable perioperative factors may play an important role in successful SDD after TKA.

Nonagenarians and Octogenarians Undergoing THA and TKA: A 10-Year Age Difference Increases Rates of In-Hospital Complications But Does Not Affect 90-Day Outcomes.

Background: The population of nonagenarians undergoing total joint arthroplasty (TJA) of the hip or knee is expected to increase, but this population may be reluctant to consider elective surgery because of their advanced age. Purpose: We sought to compare TJA outcomes between nonagenarians and octogenarians with an exact 10-year age difference. Methods: We performed a retrospective chart review, including 129 nonagenarians who underwent primary unilateral TJA for osteoarthritis in a 4-year period at a single institution and who were matched with 381 octogenarians based on sex, body mass index, Charlson Comorbidity Index, replaced joint (hip or knee), and a 10-year age difference. Ninety-day outcomes included Centers for Medicare and Medicaid Services (CMS) defined complications, unscheduled outpatient clinic visits, emergency room (ER) visits, and readmissions. No patients were lost to follow-up. Results: Nonagenarians and octogenarians had comparable rates of CMS complications (10% vs 6.3%, respectively), but nonagenarians had higher rates of CMS mechanical complications (6.2% vs 1.6%). There was 1 death in each group. Nonagenarians had longer hospital stays than octogenarians (4.1 vs 3.0 days, respectively), and a greater risk of in-hospital events and complications (60.5% vs 37.3%, respectively). The groups showed similar rates of unscheduled outpatient visits (14.7% vs 13.9%, respectively), ER visits (12.4 vs 6.6%, respectively), and readmissions (6.2% vs 7.1%, respectively). Conclusions: This retrospective study found higher rates of in-hospital complications in nonagenarians than in matched octogenarians following elective TJA, although the 2 groups showed similar rates of postdischarge complications. Further research in a larger cohort is needed.

The Complex Process of Using the Interconnected Knee Arthroplasty Device Clearance Pathway.

Background: The clearance of medical devices by the US Food and Drug Administration (FDA) has remained largely unchanged since 1976, when the Medical Device Amendments Act established a system classifying devices into 3 categories based on safety risk to the consumer. The system allows for the clearance of many orthopedics devices through the 510(k) premarket pathway, which is based on "predicate ancestors," previously cleared devices that are "substantially equivalent." Purpose: We sought to trace the predicate ancestors of modern total knee arthroplasty (TKA) devices, specifically those recently cleared for marketing by the 510(k) pathway that claim substantial equivalence to prior devices, despite potential differences in material science and design. In addition, we aimed to document which TKA devices cleared by the 510(k) pathway have substantial equivalence to devices that have since been recalled by the FDA. Methods: To create a comprehensive list of TKA devices, we used FDA Classification Process Codes corresponding to knee arthroplasty to search the FDA's databases from May 28, 1976, the start of the 510(k) process, to May 1, 2021. Of 1309 resulting devices, 89 were excluded as not related to arthroplasty. For each of the remaining devices, we analyzed the descendant devices that claimed substantial equivalence, either directly or indirectly. We used data of recalled designs to determine both the absolute number of recalled devices and the number of currently cleared devices that presented substantial equivalence claims upon predicates that have since been recalled. Results: Of 1220 knee devices cleared or approved, 6 (0.5%) were approved through the premarket approval application (PMA) process, and 1214 (99.5%) were cleared through the 510(k) pathway. Of the 1214 cleared devices, 217 (17.9%) have been recalled and 204 (16.8%) have ties to at least 1 recalled predicate device linked through generational claims of substantial equivalence. We found 90 devices (7.4%) linked directly to a recalled predicate device. Conclusions: Most knee arthroplasty devices are cleared for marketing through reliance on a complex web of equivalency to previously cleared predicates. We found that many TKA devices thus connected were cleared decades apart, with multiple iterations of design and material modifications. Many currently marketed TKA devices have claimed equivalency to predicates that have been recalled. Our findings suggest the need for novel regulatory strategies that might further patient safety while balancing the unwanted effects of regulatory burden.

Total Joint Arthroplasty in Patients With Atrial Septal Defects: What Are the 90-Day Complications?

Background: Congenital heart defects, such as atrial septal defects (ASDs) and patent foramen ovale (PFO), may increase the risk of embolic events in total hip or knee arthroplasty (THA/TKA). The objective of this study was to determine the 90-day incidence of intraoperative and postoperative embolic events and all other complications in patients with a known ASD/PFO who underwent primary hip and knee arthroplasty. Methods: This is a retrospective review of 160 patients with ASD/PFO undergoing 196 primary arthroplasties (94 THAs, 102 TKAs) at a single institution. The mean age was 64 years (standard deviation [SD] 11.1), 40.6% were male, and average body mass index was 31 kg/m2 (SD 7.2). The mean follow-up period was 19 months (SD 16). Forty-three percent of patients were on anticoagulation preoperatively. All patients received postoperative thromboprophylaxis (48% aspirin, 31% direct oral anticoagulants, 18% warfarin, 3% enoxaparin). Results: There were no embolic events identified. Fourteen patients (7%) developed complications within 90 days. Three had bleeding complications, and 8 had other nonoperative complications, which were all managed conservatively and had uneventful recoveries. Additionally, 3 patients had complications requiring reoperations: 2 for periprosthetic fractures (1 THA, 1 TKA) and 1 for a periprosthetic infection (TKA). Conclusions: In this cohort of patients with a known ASD/PFO undergoing THAs and TKAs, there were no cases of embolic events. However, it would be advisable to have a thorough cardiology evaluation to assess potential risks and benefits of defect repair prior to total joint arthroplasty and to reduce the risk of paradoxical embolic events and the necessity of potent anticoagulation. Level of evidence: Prognostic Level IV.