Outcomes of Unicompartmental Knee Arthroplasty in Patients Receiving Long-Term Anticoagulation Therapy: A Propensity-Matched Cohort Study.

BACKGROUND: Although total knee arthroplasty has been considered the gold-standard treatment for severe osteoarthritis of the knee, unicompartmental knee arthroplasty (UKA) has become an increasingly favorable alternative for single-compartment osteoarthritis of the knee. Few studies have examined potential high-risk populations undergoing this procedure. The purpose of this study was to investigate the outcomes of UKA in patients receiving long-term anticoagulation therapy. METHODS: In this study, a large administrative database was queried to identify patients undergoing UKA between 2009 and 2019, who were then divided into a cohort receiving long-term anticoagulation and a control cohort. Propensity scores were utilized to match these patients. Multivariable logistic regression was utilized to compare 90-day and 2-year complication rates between cohorts. RESULTS: Patients who were on long-term anticoagulation had significantly increased odds of extended length of stay, surgical site infection, wound complication, transfusion, deep vein thrombosis, pulmonary embolism, and readmission at 90-day follow-up. The long-term anticoagulation cohort also experienced significantly higher odds of periprosthetic joint infection and mechanical complications at 2-year follow-up; however, odds of conversion to total knee arthroplasty were not increased. CONCLUSIONS: This study demonstrated that long-term anticoagulation use was associated with poorer medical and surgical outcomes at both 90 days and 2 years postoperatively in patients undergoing UKA, even after rigorous adjustment for confounders.

Chronic Anticoagulation is Associated With Increased Risk for Postoperative Complications Following Aseptic Revision Total Hip Arthroplasty.

BACKGROUND: With an aging global population, the incidence of revision total hip arthroplasty (rTHA) is expected to increase markedly. While patients undergoing primary total hip arthroplasty who require chronic anticoagulation (AC) have been associated with increased postoperative complications, less is known about the impact of chronic AC status on postoperative complications in the rTHA setting. This study sought to compare complication rates following aseptic rTHA between patients who were on chronic AC and those who were not. METHODS: A large national database was utilized to retrospectively identify 9,421 patients who underwent aseptic rTHA between 2014 and 2019. Patients were divided into 2 cohorts: 1,790 patients (19.0%) were in the chronic AC cohort (ie, having an AC prescription filled within 6 months prior to and following rTHA), and 7,631 patients (81.0%) were not on chronic AC. Postoperative complications at 90-days and 2-years were compared between cohorts utilizing univariate and multivariate analyses, controlling for sex, age, and comorbidities. RESULTS: At 90-days, chronic AC patients had increased odds of prosthetic joint infections (PJIs) (odds ratio [OR] 3.2, P < .001), surgical site infections (OR 3.6, P < .001), and mechanical prosthetic complications (OR 3.5, P < .001), which included any aseptic loosening, implant dislocation, or broken prosthetic. At 2-years, chronic AC patients had increased odds of PJI (OR 3.3, P < .001) as well as mechanical prosthetic complications (OR 3.2, P < .001). Chronic AC patients were also at increased risk for reoperation within 2 years after initial aseptic rTHA (OR 1.9, P < .001). CONCLUSIONS: Patients on chronic AC have significantly higher odds of 90-day and 2-year complications after aseptic rTHA. This includes increased odds of PJI, surgical site infection, and mechanical prosthetic complications. Patients receiving chronic AC who undergo rTHA should be counseled on the risk-benefit ratio of their chronic AC status in a multidisciplinary setting to optimize their postoperative outcomes.

Does the Primary Surgical Approach Matter When Choosing the Approach for Revision Total Hip Arthroplasty?

BACKGROUND: Multiple surgical approaches are used for primary total hip arthroplasty (pTHA) and revision total hip arthroplasty (rTHA). This study sought to investigate prevalence of discordance of pTHA and rTHA surgical approaches and to evaluate how approach concordance impacts postoperative outcomes. METHODS: A retrospective review of patients who underwent rTHA from 2000 to 2021 was conducted at 3 large urban academic centers. Patients who had minimum 1-year follow-up post-rTHA were included and grouped based on whether they received pTHA via a posterior (PA), direct anterior (DA), or laterally based (DL) approach, and by concordance of index rTHA approach with their pTHA approach. Of the 917 patients studied, 839 (91.5%) were included in the concordant cohort and 78 (8.5%) in the discordant cohort. Patient demographics, operative characteristics, and postoperative outcomes were compared. RESULTS: Discordance was most prevalent in the DA-pTHA subset (29.5%), compared to the DL-pTHA subset (14.7%) or PA-pTHA subset (3.7%). Discordance varied significantly between primary approaches among all revisions, with DA-pTHA patients having the highest discordance rate for patients revised for aseptic loosening (46.3%, P < .001), fracture (22.2%, P < .001), and dislocation (33.3%, P < .001). There were no differences between groups in dislocation rate, re-revision for infection, or re-revision for fracture. CONCLUSION: The results of this multicenter study showed patients who received pTHA via the DA were more likely to receive rTHA via a discordant approach compared to other primary approaches. Since approach concordance did not impact dislocation, infection, or fracture rates after rTHA, surgeons can feel reassured using a separate approach for rTHA. LEVEL III EVIDENCE: Retrospective Cohort Study.

Users' Concerns About Endometriosis on Social Media: Sentiment Analysis and Topic Modeling Study.

BACKGROUND: Endometriosis is a debilitating and difficult-to-diagnose gynecological disease. Owing to limited information and awareness, women often rely on social media platforms as a support system to engage in discussions regarding their disease-related concerns. OBJECTIVE: This study aimed to apply computational techniques to social media posts to identify discussion topics about endometriosis and to identify themes that require more attention from health care professionals and researchers. We also aimed to explore whether, amid the challenging nature of the disease, there are themes within the endometriosis community that gather posts with positive sentiments. METHODS: We retrospectively extracted posts from the subreddits r/Endo and r/endometriosis from January 2011 to April 2022. We analyzed 45,693 Reddit posts using sentiment analysis and topic modeling-based methods in machine learning. RESULTS: Since 2011, the number of posts and comments has increased steadily. The posts were categorized into 11 categories, and the highest number of posts were related to either asking for information (Question); sharing the experiences (Rant/Vent); or diagnosing and treating endometriosis, especially surgery (Surgery related). Sentiment analysis revealed that 92.09% (42,077/45,693) of posts were associated with negative sentiments, only 2.3% (1053/45,693) expressed positive feelings, and there were no categories with more positive than negative posts. Topic modeling revealed 27 major topics, and the most popular topics were Surgery, Questions/Advice, Diagnosis, and Pain. The Survey/Research topic, which brought together most research-related posts, was the last in terms of posts. CONCLUSIONS: Our study shows that posts on social media platforms can provide insights into the concerns of women with endometriosis symptoms. The analysis of the posts confirmed that women with endometriosis have to face negative emotions and pain daily. The large number of posts related to asking questions shows that women do not receive sufficient information from physicians and need community support to cope with the disease. Health care professionals should pay more attention to the symptoms and diagnosis of endometriosis, discuss these topics with patients to reduce their dissatisfaction with doctors, and contribute more to the overall well-being of women with endometriosis. Researchers should also become more involved in social media and share new science-based knowledge regarding endometriosis.

Time to Venous Thromboembolism Events Following Total Hip Arthroplasty: A Comparison Between Aspirin and Warfarin.

BACKGROUND: The attitude and approach of orthopedic community for minimizing venous thromboembolism (VTE) has evolved over the last decade with the trend toward use of aspirin (and mechanical modalities) in lieu of aggressive anticoagulation. The optimal length of VTE prophylaxis following total hip arthroplasty (THA) still remains unknown. This study aimed to determine the timing of VTE in patients who received aspirin compared to warfarin, and determine if 30 days of prophylaxis remain adequate. METHODS: This is a retrospective study of 18,003 patients undergoing primary and revision THA at a single institution between January 2008 and August 2020. During this time, our institution underwent a transition from the use of warfarin to aspirin as the main method for VTE prophylaxis. Symptomatic deep vein thrombosis and pulmonary embolism occurring within 90 days of surgery were identified from medical records and phone call logs. Aspirin and warfarin cohorts were matched to account for demographic and comorbidity differences. Timing of pulmonary embolism was determined based on either the date of diagnostic imaging or patient-provider phone calls confirming diagnosis. RESULTS: The cohorts included 46 patients in the warfarin group and 46 in the aspirin group. Time to VTE was significantly shorter in the warfarin group compared to aspirin (P = .021) with a median time to VTE of 3 days (interquartile range 2-14) and 10 days (interquartile range 4-19) respectively. Over 90% of the events occurred within 32 or 30 days of surgery in the warfarin and aspirin groups respectively. CONCLUSION: Based on the findings, a 30-day aspirin prophylaxis remains appropriate for patients undergoing THA.

Demand Matching Total Joint Replacement Patients Results in Reduction of Post-Discharge Costs.

BACKGROUND: The shift from fee-for-service to value-based care has focused payers and providers on resource utilization. One important component of value-based care is to reduce the use of post-discharge (PD) services in a clinically appropriate manner following total joint arthroplasty (TJA). Demand matching in healthcare is the process of tailoring appropriate medical care to a patient with respect to that patient's specific medical needs and social determinants. Outcomes following the implementation of a demand-matching algorithm for coordinating PD services after TJA were analyzed in this study. METHODS: Payment data from all Medicare patients undergoing primary unilateral TJA between July 2014 and December 2018 from a single orthopedic practice were included. These payments were separated into acute and PD care. The initial acute and PD costs were compared to costs at the end of the 4-year study period using multiple linear regression and chi-square. RESULTS: A total of 9,638 patients (4,212 total hip arthroplasties and 5,430 total knee arthroplasties) were included. Acute costs of TJA were stable averaging $13,712.00. PD costs fell steadily from a baseline average of $7,319.00 in July 2014 to $4,678.00 in December 2018 (P < .001), representing a 36.1% decline. Discharge to home increased steadily from 45.8% to 79.9% during the same interval (P < .001.) CONCLUSION: Our results demonstrate a statistically significant reduction in PD costs over a 4-year period using a demand-matching strategy to align with the Centers for Medicare and Medicaid Services mandate for value-based care. Based on these data, we conclude that thoughtful preoperative assessment of patient factors such as social determinants and medical comorbidities could allow for cost reduction through better utilization of PD services.

Assessment of dual-tasking during a dynamic balance task using a smartphone app: a pilot study.

[Purpose] To assess if the instrumented Timed Up and Go (iTUG) task score calculated with an iPhone application can detect gait changes under dual-tasking conditions. [Participants and Methods] Twenty participants (age 38.30 ± 12.54, 12 females) were asked to complete the TUG as a single task and under two dual-tasking conditions: 1) verbal fluency and 2) mental calculation. We used a smartphone, stopwatch, digital camera, and wearable sensor to calculate the dependent variables which included time, step count, gait speed, and iTUG score and, the dual-tasking cost (DTC) of those variables. We used Friedman analyses of variance and Wilcoxon tests for statistical analyses. [Results] the iTUG score, step count, gait speed, and the time measured by the stopwatch and wearable sensor differed significantly for all tasks, but the smartphone time did not. [Conclusion] We conclude that the iTUG score could be used as a sensitive measure for identifying gait changes under dual-tasking conditions. With the growing demands of telehealth, using technology as an objective tool for movement analysis is needed for clinicians and payers. Our findings demonstrate the potential value of the iTUG score to assess and track patient's progress.

Capsular Management in Direct Anterior Total Hip Arthroplasty: A Randomized, Single-Blind, Controlled Trial.

BACKGROUND: The direct anterior approach (DAA) is a popular approach to total hip arthroplasty (THA). Unlike the posterior approach, the importance of anterior capsular management is unknown. This randomized controlled trial compares capsular repair versus capsulectomy. METHODS: This single-surgeon, single-blinded, parallel-group randomized controlled trial occurred between 2013 and 2016. Patients undergoing unilateral, primary THA for osteoarthritis consented to undergo blinded, simple randomization to anterior capsulotomy with repair or anterior capsulectomy. Primary outcome measures included hip range of motion, hip flexion strength, and pain with seated hip flexion. Secondary outcome measures included surgical time, estimated blood loss, postoperative complications, and hip disability and osteoarthritis outcome score. Data were prospectively collected intraoperatively, six weeks, six months, an average of over 5 years postoperatively. RESULTS: Ninety-eight patients were ultimately enrolled in the trial; 50 received capsulectomy and 48 received capsulotomy. No significant differences were seen in preoperative demographics or in primary or secondary outcomes during this study. No difference was seen in pain at final follow-up at average > 5 years postoperatively. CONCLUSION: This study demonstrates that capsular management in DAA THA does not affect postoperative pain or range of motion. The anterior capsule's role in prosthetic stability after DAA THA remains uncertain, but it does not currently appear that repair provides benefit and may lead to increased surgical time and blood loss. As such, capsular management in DAA THA is at surgeon discretion.

Thirty Days of Aspirin for Venous Thromboembolism Prophylaxis Is Adequate Following Total Knee Arthroplasty, Regardless of the Dose Used.

BACKGROUND: The optimal length of aspirin prophylaxis to minimize venous thromboembolism (VTE) following total knee arthroplasty (TKA) remains unknown. This study aimed to determine the timing of VTE after TKA in patients who received low and high dose aspirin, and determine if 30 days of prophylaxis remains adequate. METHODS: We retrospectively reviewed records of 9208 patients undergoing primary TKA between 2010 and 2020 who received either low (81 mg twice daily, n = 4413) or high (325 mg twice daily, n = 4795) dose aspirin for VTE prophylaxis. Symptomatic VTEs occurring within 90 days of surgery were identified from medical records and phone call logs. Major bleeding events (MBE) within the first 30 days were also documented. Time to event was recorded. RESULTS: Overall, 88 patients (1.0%) developed symptomatic VTE, with no significant differences in incidence between the low (n = 40, 0.9%) and high (n = 48, 1.0%) dose groups (P = .669). The median time to VTE was 8 days (interquartile range [IQR] 2-15.5), median time to deep vein thrombosis was 12 days (IQR 5-18), and median time to pulmonary embolism was 5 days (IQR 1.5-15). There was a similar distribution in time to VTE in both the low and high dose groups. Aside from a single DVT occurring at day 44, all VTE occurred within 30 days of surgery. During the prophylactic time period, 41 patients (0.4%) developed MBE, which tended to occur more frequently (0.6% vs 0.3%, P = .018) and earlier in the high dose group. CONCLUSION: Based on the findings, a 30-day low or high dose aspirin regimen remains optimal for prevention of VTE without increasing MBE in TKA patients.

Outcomes Following Revision for Mechanically Assisted Crevice Corrosion in a Single Femoral Design.

BACKGROUND: Mechanically assisted crevice corrosion (MACC) is a described complication following metal-on-polyethylene (MoP) total hip arthroplasty (THA). The literature regarding outcomes following revision for MACC suggests that complication rates are high. The purpose of this investigation is to add to this literature with the largest reported series to date. METHODS: This is a retrospective cohort study of 552 consecutive patients who underwent 621 MoP primary THAs. We identified patients who subsequently underwent revision THA for a diagnosis of MACC. All patients were implanted with the same implant combination (Accolade I stem/cobalt-chromium low friction ion treatment femoral head). Patient demographic, surgical, and laboratory data were collected. Follow-up was calculated from the revision surgery and Hip Disability and Osteoarthritis Outcome Score Joint Replacement and hip subjective values (HSV) were examined at final follow-up. Descriptive statistics were performed. RESULTS: The revision rate for MACC was 11.6% and mean time to revision was 6.6 (±2.4) years. Revised patients (n = 69) had a mean preoperative serum cobalt-chromium ratio of 3.5 (±2.4). There were 8 cases of gross trunnion failure. At mean 3.2 (±1.9) years following revision, the overall major complication rate was 11.6% with a 5.8% reoperation rate. At final follow-up, mean Hip Disability and Osteoarthritis Outcome Score Joint Replacement scores were 83.2 (±15.6) and mean hip subjective value was 77.6 (±17.4). Revision resulted in significant increases in both parameters (P < .001). CONCLUSION: The incidence of MACC in MoP THA is likely higher than previously reported, particularly for certain implant combinations. Revision surgery for MACC can achieve good outcomes but a high clinical suspicion with early detection and revision is likely key to success.

Stress Tracker-Detecting Acute Stress From a Trackpad: Controlled Study.

BACKGROUND: Stress is a risk factor associated with physiological and mental health problems. Unobtrusive, continuous stress sensing would enable precision health monitoring and proactive interventions, but current sensing methods are often inconvenient, expensive, or suffer from limited adherence. Prior work has shown the possibility to detect acute stress using biomechanical models derived from passive logging of computer input devices. OBJECTIVE: Our objective is to detect acute stress from passive movement measurements of everyday interactions on a laptop trackpad: (1) click, (2) steer, and (3) drag and drop. METHODS: We built upon previous work, detecting acute stress through the biomechanical analyses of canonical computer mouse interactions and extended it to study similar interactions with the trackpad. A total of 18 participants carried out 40 trials each of three different types of movement-(1) click, (2) steer, and (3) drag and drop-under both relaxed and stressed conditions. RESULTS: The mean and SD of the contact area under the finger were higher when clicking trials were performed under stressed versus relaxed conditions (mean area: P=.009, effect size=0.76; SD area: P=.01, effect size=0.69). Further, our results show that as little as 4 clicks on a trackpad can be used to detect binary levels of acute stress (ie, whether it is present or not). CONCLUSIONS: We present evidence that scalable, inexpensive, and unobtrusive stress sensing can be done via repurposing passive monitoring of computer trackpad usage.

Investigating the association between population density and travel patterns in Indian cities-An analysis of 2011 census data.

Many transport planners consider urban population density to be a significant determinant of travel behaviour. Much of the evidence for this comes from research in low-density, high-income settings. The 2011 Census of India reported mode of travel to work and distance for the first time. We have used these data to investigate the effect of urban density on commute travel patterns at city-level for Indian cities. In addition, we investigated the relationship between travel behaviour and other city-level variables. Using regression, we found almost no independent effect of density on the mode share of walk, cycle, motorised two-wheelers, cars and public transport, after controlling for population and income levels for the cities. Further, it appears that once density levels are greater than ~80 persons per hectare (pph), other factors become more important in determining travel patterns in cities. This evidence has significant implications for urban planning and transport policy in Indian cities and for many other low- and middle-income cities where average density tends to be higher than ~80 pph. For these cities, growth in the use of sustainable transport may not depend on further densification of already dense cities, but on details of how neighbourhoods and streets are designed.

Effectiveness of Daily Use of Bilateral Custom-Made Ankle-Foot Orthoses on Balance, Fear of Falling, and Physical Activity in Older Adults: A Randomized Controlled Trial.

BACKGROUND: Foot problems are prevalent in older adults, which may increase the risk and concern for falls. Ankle-foot orthoses (AFO) have been shown to be effective in the stabilization of lower extremities, but their long-term effectiveness in improving balance and their potential to encourage older adults to become more physically active are still debated. OBJECTIVE: This randomized controlled trial investigated the effectiveness of daily use of a custom-made AFO on balance, fear of falling, and physical activity in older adults. STUDY DESIGN: Forty-four older adults with concern about or at risk for falling were randomly allocated to either the control group (CG; 77.3% female, age 75.6 ± 6.5 years, BMI 29.3 ± 6.4) or the intervention group (IG; 63.6% female, age 73.7 ± 6.3 years, BMI = 27.8 ± 4.8). The IG received walking shoes and bilateral custom-made AFO. The CG received only walking shoes. At the baseline and 6-month follow-ups, balance and physical activity were assessed using validated wearable instrumentation and fear of falling was assessed using the Fall Efficacy Scale-International (FES-I). Adherence and acceptability toward wearing the AFO were assessed using self-reported questionnaires at the 6-month follow-up. RESULTS: No significant between-group difference was observed at baseline (p = 0.144-0.882). Compared to baseline and the CG, hip, ankle, and center-of-mass (COM) sways were significantly reduced at the 6-month follow-up in the IG while standing with the feet together during the eyes-open condition (p = 0.005-0.040). Within the IG, the FES-I was reduced significantly (p = 0.036) and there was an increasing trend in the number of walking bouts with a medium effect size (d = 0.52, p = 0.440) compared to baseline. However, there were no significant changes in FES-I and physical activity measures in the CG (p = 0.122-0.894). The reduction in COM sway in the IG was moderately correlated with adherence (r = -0.484, p = 0.047) and strongly correlated with baseline COM sway (r = -0.903, p < 0.001). CONCLUSION: Results suggest that bilateral custom-made AFO plus walking shoes is effective in improving balance compared to walking shoes alone, and it significantly reduces the fear of falling, with a nonsignificant but noticeable positive trend in physical activity, compared to baseline. The results also suggest that older adults with poor balance at baseline and higher daily adherence to using the AFO will gain more benefit from the AFO intervention.

Contextualising Safety in Numbers: a longitudinal investigation into change in cycling safety in Britain, 1991-2001 and 2001-2011.

INTRODUCTION: The 'Safety in Numbers' (SiN) phenomenon refers to a decline of injury risk per time or distance exposed as use of a mode increases. It has been demonstrated for cycling using cross-sectional data, but little evidence exists as to whether the effect applies longitudinally -that is, whether changes in cycling levels correlate with changes in per-cyclist injury risks. METHODS: This paper examines cross-sectional and longitudinal SiN effects in 202 local authorities in Britain, using commuting data from 1991, 2001 and 2011 censuses plus police -recorded data on 'killed and seriously injured' (KSI) road traffic injuries. We modelled a log-linear relationship between number of injuries and number of cycle commuters. Second, we conducted longitudinal analysis to examine whether local authorities where commuter cycling increased became safer (and vice versa). RESULTS: The paper finds a cross-sectional SiN effect exists in the 1991, 2001 and 2011 censuses. The longitudinal analysis also found a SiN effect, that is, places where cycling increased were more likely to become safer than places where it had declined. Finally, these longitudinal results are placed in the context of changes in pedestrian, cyclist and motorist safety. While between 1991 and 2001 all modes saw declines in KSI risk (37% for pedestrians, 36% for cyclists and 27% for motor vehicle users), between 2001 and 2011 pedestrians and motorists saw even more substantial declines (41% and 49%), while risk for cyclists increased by 4%. CONCLUSION: The SiN mechanism does seem to operate longitudinally as well as cross-sectionally. However, at a national level between 2001-11 it co-existed with an increase in cyclist injury risk both in absolute terms and in relation to other modes.

Effects of speed and direction of perturbation on electroencephalographic and balance responses.

The modulation of perturbation-evoked potential (PEP) N1 as a function of different biomechanical characteristics of perturbation has been investigated before. However, it remains unknown whether the PEP N1 modulation contributes to the shaping of the functional postural response. To improve this understanding, we examined the modulation of functional postural response in relation to the PEP N1 response in ten healthy young subjects during unpredictable perturbations to their upright stance-translations of the support surface in a forward or backward direction at two different amplitudes of constant speed. Using independent components from the fronto-central region, obtained from subject-specific head models created from the MRI, our results show that the latency of onset of the functional postural response after the PEP N1 response was faster for forward than backward perturbations at a constant speed but was not affected by the speed of perturbation. Further, our results reinforce some of the previous findings that suggested that the N1 peak amplitude and peak latency are both modulated by the speed of perturbation but not by the direction of the perturbation. Our results improve the understanding of the relation between characteristics of perturbation and the neurophysiology of reactive balance control and may have implications for the design of brain-machine interfaces for populations with a higher risk of falls.

Proper Use of Antibiotic Agents in the Management of Musculoskeletal Infection.

Musculoskeletal infections have plagued all creatures for millions of years. The ability to manage infection via antibiotic agents has emerged only in the past 100 years. The use of antibiotic agents has not always been appropriate and judicious, which has led to widespread microbial resistance to certain antibiotic agents. Although antibiotic resistance is a considerable consequence of inappropriate antibiotic use, the systemic adverse effects of chronic antibiotic use on patients have largely been ignored. These systemic adverse effects may have been prevented if surgeons had a better understanding of the microbiology of the pathogens involved in musculoskeletal infections. Most importantly, the formation of biofilm as an infection becomes chronic makes bacteria relatively impervious to systemic antibiotic agents. Therefore, surgeons must understand the difference between and how to appropriately manage acute and chronic musculoskeletal infections. This dichotomous approach in the management of infection also must be applied in patients with periprosthetic joint infection. The appropriate use of antibiotic agents in the management of musculoskeletal infections may help mitigate the spread of antibiotic resistance and the adverse effects of inappropriate antibiotic use.

Patients With Infected Total Hip Arthroplasty Undergoing 2-Stage Exchange Arthroplasty Experience Massive Blood Loss.

BACKGROUND: Two-stage exchange arthroplasty is the preferred treatment for chronic periprosthetic joint infection following total hip arthroplasty (THA). These patients are at high risk of substantial blood loss and perioperative blood transfusion. Our study aimed at determining risk factors for blood transfusion during a 2-stage exchange for infected THA. METHODS: Medical records of 297 patients with infected THA who underwent 2-stage exchange arthroplasty from 1997 to 2016 were reviewed. Blood loss was calculated using a validated formula. Transfusion data, clinical information, and operative data were gathered to determine predictors of blood loss and risk factors for perioperative allogeneic blood transfusion. RESULTS: Calculated blood loss was significantly higher during reimplantation than resection arthroplasty (5156.0 ± 3402 mL vs 3706.9 ± 2148 mL; P < .0001). Blood transfusion was needed in 81% after resection and 81.1% after reimplantation. Allogeneic blood transfusion averaged 3.6 ± 1.8 units for stage 1 and 4.2 ± 2.9 units for stage 2 (P = .0066). Patient characteristics that increased the likelihood for perioperative blood transfusions were increasing preoperative international normalized ratio, type 2 diabetes, current smoking, age, and transfusion requirement in the first stage. Tranexamic acid usage was associated with decreased blood loss. CONCLUSION: Patients with periprosthetic joint infection following THA have significant blood loss during both stages of exchange arthroplasty, especially reimplantation. Hematological optimization should be considered in all patients requiring a transfusion after the first stage, as these patients are at greater risk of requiring transfusion after the second stage. The use of tranexamic acid dramatically decreases the risk of requiring a transfusion in both stages and should be more ubiquitously incorporated into blood management protocols.

How Much Pain Is Significant? Defining the Minimal Clinically Important Difference for the Visual Analog Scale for Pain After Total Joint Arthroplasty.

BACKGROUND: The ability to detect changes in patient-perceived pain after total joint arthroplasty (TJA) is critical to manage postoperative pain. The minimal clinically important difference (MCID) for visual analog scale for pain (VAS-P) has not been investigated in this population. This study investigated the MCID for VAS-P in the TJA population. METHODS: Postoperative pain scores were collected on 139 total hip arthroplasty (THA) and 165 total knee arthroplasty (TKA) patients. VAS-P was measured and Likert scores for changes in pain recorded together throughout the hospitalization per patient. Using a linear mixed model, the mean difference between preceding and current VAS-P was calculated and correlated with Likert score, when the patient reported at least slight improvement or worsening in pain, defining the MCID. Minimal detectable change was calculated using the VAS-P standard error of the means for patients reporting "no change." RESULTS: For THA, the overall mean and average highest VAS-P were 35.0 mm and 50.4 mm, respectively. For TKA, the overall mean and average highest VAS-P were 42.6 mm and 61.1 mm, respectively. The minimal detectable change in VAS-P was 14.9 mm for THA and 16.1 mm for TKA. The MCID for THA and TKA pain improvement was -18.6 mm and -22.6 mm, respectively, and for worsening was 23.6 mm and 29.1 mm, respectively. CONCLUSION: In the postoperative TJA population, VAS-P MCID changes depend on the type of surgical intervention, and whether pain is improving or worsening. Statistically significant VAS-P, improving -18.6 mm and -22.6 mm for THA and TKA patients, respectively, sets a reasonable threshold to identify clinically meaningful pain intervention with high specificity.

Periarticular Ropivacaine Cocktail Is Equivalent to Liposomal Bupivacaine Cocktail in Bilateral Total Knee Arthroplasty.

BACKGROUND: This study compares the effectiveness of 2 commonly used periarticular injection formulations: liposomal bupivacaine and bupivacaine (EXP) and ropivacaine, epinephrine, ketorolac, and clonidine (ROP) in patients undergoing bilateral total knee arthroplasty or unicompartmental knee arthroplasty. METHODS: Twenty-six total knee arthroplasty patients (52 knees) and 3 unicompartmental knee arthroplasty patients (6 knees) undergoing simultaneous, bilateral arthroplasty were randomized to receive periarticular injections in a blinded fashion. Even birth year patients were selected for PAI of EXP in the right knee and ROP in the left knee. This was reversed for odd birth years. Visual analog scale pain scores for each knee and patient perceived difference in knee functional recovery were recorded during physical therapy, throughout the hospitalization. RESULTS: There was no difference in visual analog scale pain scores between the EXP and ROP injected knees at any time point during the first 2 days after surgery. Postoperative pain scores averaged 41.9 mm (range 0-100 mm) for EXP and 43.1 mm (range 0-100 mm) for ROP. Patients were unable to detect a difference in the functional recovery between their knees on postoperative day 0, 1, or 2. No complications as a result of either periarticular injection occurred. CONCLUSION: Periarticular injections of EXP and ROP are equally effective after knee arthroplasty and patients do not appreciate differences between knees as determined by pain score or perceived functional recovery during the first 2 days after bilateral knee arthroplasty. This study demonstrates that a liposomal bupivacaine injection does not add an incremental benefit for pain control compared to a less expensive injection formulation.