Better restoration of joint line obliquity in tibia first restricted kinematic alignment versus mechanical alignment TKA.

INTRODUCTION: In total knee arthroplasty (TKA), suboptimal restoration of joint line obliquity (JLO) and joint line height (JLH) may lead to diminished implant longevity, increased risk of complications, and reduced patient reported outcomes. The primary objective of this study is to determine whether restricted kinematic alignment (rKA) leads to improved restoration of JLO and JLH compared to mechanical alignment (MA) in TKA. MATERIALS AND METHODS: This retrospective study assessed patients who underwent single implant design TKA for primary osteoarthritis, either MA with manual instrumentation or rKA assisted with imageless navigation robotic arm TKA. Pre- and post-operative long standing AP X-ray imaging were used to measure JLO formed between the proximal tibial joint line and the floor. JLH was measured as the distance from the femoral articular surface to the adductor tubercle. RESULTS: Overall, 200 patients (100 patients in each group) were included. Demographics between the two groups including age, sex, ASA, laterality, and BMI did not significantly differ. Distribution of KL osteoarthritis classification was similar between the groups. For the MA group, pre- to post-operative JLO significantly changed (2.94° vs. 2.31°, p = 0.004). No significant changes were found between pre- and post-operative JLH (40.6 mm vs. 40.6 mm, p = 0.89). For the rKA group, no significant changes were found between pre- and post-operative JLO (2.43° vs. 2.30°, p = 0.57). Additionally, no significant changes were found between pre- and post-operative JLH (41.2 mm vs. 42.4 mm, p = 0.17). Pre- to post-operative JLO alteration was five times higher in the MA group compared to the rKA group, although this comparison between groups did not reach statistical significance (p = 0.09). CONCLUSION: rKA-TKA results in high restoration accuracy of JLO and JLH, and demonstrates less pre- and post-operative JLO alteration compared to MA-TKA. With risen interest in joint line restoration accuracy with kinematic alignment, these findings suggest potential advantages compared to MA. Future investigation is needed to correlate between joint line restoration accuracy achieved by rKA and enhanced implant longevity, reduced risk of post-operative complications, and heightened patient satisfaction.

Effect of inverse kinematic alignment total knee arthroplasty on coronal alignment of the ankle joint in patients with varus knee deformity.

INTRODUCTION: Varus or valgus knee deformities influence ankle coronal alignments. The impact of Total Knee Arthroplasty (TKA) on ankle joint alignment has not been entirely illustrated. Inverse Kinematic Alignment (iKA) is a surgical philosophy that aims to restore soft tissue balance, function, and native anatomy within validated boundaries to restore restrictive native kinematics. Therefore, this study aimed to investigate the postoperative association of patient-specific alignment on the coronal alignment of the ankle in patients with varus knee deformity who underwent iKA TKA. We hypothesized that greater preoperative varus malalignments would correlate with significant postoperative ankle coronal alignment changes. METHODS: This retrospective study of a prospective collected cohort assessed patients who underwent imageless navigation assisted robotic TKA using a single implant design for primary osteoarthritis between January 2022 and August 2023. Preoperative and postoperative full-length standing anteroposterior X-ray imaging was used to measure Hip-Knee-Ankle (HKA), Tibial Plafond Inclination (TPI), Talar inclination (TI), and Tibiotalar Tilt (TTT) angles. Patients were subsequently divided into groups of neutral varus) < 10°) and severe varus (≥ 10°) according to the preoperative HKA angle. RESULTS: Significant changes in preoperative and postoperative HKA angles were found in the severe varus (14.5° vs. 6.4°, p < 0.001) group. Changes were also significant between preoperative and postoperative TPI and TI angles in the severe varus group; however, TTT did not reach statistical significance. Delta change from pre- to postoperative HKA was significantly higher for the severe varus group (8.1° vs. 0.8°, p < 0.019). Delta change of TPI, TI and TTT did not differ between groups. CONCLUSION: Coronal knee alignment after TKA affects coronal alignment of the ankle. iKA technique in TKA for varus knee deformity preserves or minimizes substantial coronal alignment changes of the ankle joint. These findings may add to the benefits reported for patient specific alignment TKA techniques. LEVEL OF EVIDENCE: III.

The role of MRI in the diagnosis of aseptic loosening following total hip arthroplasty.

INTRODUCTION: The role of advanced imaging in diagnosing aseptic implant loosening following total hip arthroplasty (THA) remains unclear. This study aimed to assess the diagnostic value of magnetic resonance imaging (MRI) in detecting aseptic loosening. METHODS: This was a retrospective review of 342 consecutive patients who underwent revision THA between July 2011 and April 2023 and had a pelvis MRI as part of the preoperative diagnostic evaluation. Among them, 62 patients had an intraoperative diagnosis of aseptic loosening of either the femoral or acetabular component. Patients were stratified based on the concordance between their MRI and radiographs findings. RESULTS: Preoperative MRI showed signs of aseptic loosening in 25/62 patients (sensitivity = 40.3%). Similarly, preoperative radiographs demonstrated signs of aseptic loosening in 27 patients (43.5%). Twelve patients (19.4%) had both MRI and radiographs predictive of aseptic loosening, 22 patients (35.5%) did not show signs of aseptic loosening in either MRI or radiographs, and for 28 patients (45.2%), the results were discordant. Among the patients with a negative radiograph for aseptic loosening (n = 35), 13 patients (37.1%) showed signs of aseptic loosening on MRI. CONCLUSION: Aseptic loosening remains an elusive diagnosis, and the findings of this study suggest that the utility of MRI and radiographs as part of the diagnostic process is limited. However, in cases of presumed aseptic loosening with inconclusive radiographs findings, MRI may play a role in improving the diagnostic process. LEVEL OF EVIDENCE: III.

Higher rates of intraoperative fractures with compaction broaching compared to conventional broaching during hip hemiarthroplasty for femoral neck fractures.

PURPOSE: Intraoperative periprosthetic femoral fracture (IPFF) is a known iatrogenic complication during hemiarthroplasty (HA) which may lead to inferior outcomes. The risk factors for IPFF during HA in displaced femoral neck fractures (FNF) remains to be fully elucidated. This study aims to compare IPFF rates between compaction broaching and conventional broaching techniques for cementless HA in FNF. METHODS: We retrospectively reviewed institutional surgical data of patients who underwent cementless HA for displaced FNF from January 2010 to January 2022. Patients were stratified into two groups based on the broaching system: conventional broaching and compaction broaching. The presence, location, and treatment of IPFF were assessed for both groups. Effect of IPFF on postoperative weight-bearing status, mortality readmission and revision rates were compared between groups. RESULTS: A total of 1,586 patients included in the study. 1252 patients (78.9%) in the conventional broaching group and 334 patients (21.1%) in the compaction broaching group. A total of 104 IPFF were found (6.5%). As compared to conventional broaching, compaction broaching was associated with significant higher IPFF rates (12.9% vs. 4.9%, p < 0.001, OR 2.84, CI 1.88-4.30). The location of the IPFF was similar between groups (p = 0.366), as well as the intraoperative treatment (p = 0.103) and postoperative weight-bearing status (p = 0.640). Surgical time, mortality rates, readmission rates and revision rates were comparable between groups. In a multivariate regression analysis, compaction broaching (OR, 4.24; p < 0.001) was independently associated with IPFF. CONCLUSIONS: This study reveals higher rates of IPFF associated with compaction broaching. Although this finding may have minimal clinical relevance, surgeons should consider these results when considering implant selection.

The Impact of Culture Negativity on the Outcomes of Revision Total Knee Arthroplasty for Chronic PJI.

Culture-positive (CP) and culture-negative (CN) periprosthetic joint infections (PJI) remain a crucial area of research; however, current studies comparing these infections rely on unstandardized outcome reporting tools. Our study aimed to compare the outcomes of two-stage revision of CP and CN PJI using the standardized Musculoskeletal Infection Society (MSIS) outcome reporting tool. We retrospectively reviewed 138 patients who were diagnosed with PJI and indicated for two-stage revision total knee arthroplasty (rTKA). The majority of patients in both CP and CN cohorts achieved infection control without the need for reoperation (54.1% and 62.5%, respectively). There was a significant difference in the overall distribution of MSIS outcomes (p = 0.043), with a significantly greater rate of CN patients falling into Tier 1 (infection control without the use of suppressive antibiotics) (52.5% versus 29.6%, p = 0.011). There was also a significant difference in the distribution of septic versus aseptic reoperations after 2nd stage (p = 0.013), with more CP reoperations being septic and more CN reoperations being aseptic. The duration from first to second stage was significantly shorter in the CN cohort (p = 0.002). While overall infection control was similar between cohorts, these data suggest that the outcomes of two-stage rTKA are favorable in cases of CN PJI.

How Has the Total Hip Arthroplasty Patient Population Changed? A Ten-Year Analysis of Total Hip Arthroplasty Patients From 2013 to 2022: A Retrospective, Single-Center Study.

BACKGROUND: Over the past decades, utilization of total hip arthroplasty (THA) has steadily increased. Understanding the demographic trends of THA patients can assist in projecting access to care. This study sought to assess the temporal trends in THA patient baseline characteristics and socioeconomic factors. METHODS: We retrospectively analyzed 16,296 patients who underwent primary elective THA from January 1, 2013, to December 31, 2022. Demographic data, including age, sex, race, body mass index (BMI), Charlson comorbidity index, insurance, and socioeconomic status, as determined by median income by patients' zip code, were collected. The trends of these data were analyzed using the Mann-Kendall test. RESULTS: Over the past decade at our institution, patient age (2013: 62.1 years to 2022: 65.1 years, P = .001), BMI (2013: 29.0 to 2022: 29.5, P = .020), and mean Charlson comorbidity index (2013: 2.4 to 2022: 3.1, P = .001) increased. The proportion of Medicare patients increased from 48.4% in 2013 to 54.9% in 2022 (P = .001). The proportion of African American patients among the THA population increased from 11.3% in 2013 to 13.0% in 2022 (P = .012). Over this period, 90-day readmission and 1-year revision rates did not significantly change (2013: 4.8 and 3.0% to 2022: 3.4 and 1.4%, P = .107 and P = .136, respectively). The proportion of operations using robotic devices also significantly increased (2013: 0% to 2022: 19.1%; P < .001). CONCLUSIONS: In the past decade, the average age, BMI, and comorbidity burden of THA patients have significantly increased, suggesting improved access to care for these populations. Similarly, there have been improvements in access to care for African American patients. Along with these changes in patient demographics, we found no change in 90-day readmission or 1-year revision rates. Continued characterization of the THA patient population is vital to understanding this demographic shift and educating future strategies and improvements in patient care.

Surgeons Experience Greater Physiologic Stress and Strain in the Direct Anterior Approach Than the Posterior Approach for Total Hip Arthroplasty.

BACKGROUND: The direct anterior approach (DAA) and posterior approach (PA) for total hip arthroplasty (THA) have advantages and disadvantages, but their physiologic burden to the surgeon has not been quantified. This study was conducted to determine whether differences exist in surgeon physiological stress and strain during DAA in comparison to PA. METHODS: We evaluated a prospective cohort of 144 consecutive cases (67 DAA and 77 PA). There were 5, high-volume, fellowship-trained arthroplasty surgeons who wore a smart-vest that recorded cardiorespiratory data while performing primary THA DAA or PA. Heart rate (beats/minute), stress index (correlates with sympathetic activations), respiratory rate (respirations/minute), minute ventilation (L/min), and energy expenditure (calories) were recorded, along with patient body mass index and operative time. Continuous data was compared using t-tests or Mann Whitney U tests, and categorical data was compared with Chi-square or Fischer's exact tests. RESULTS: There were no differences in patient characteristics. Compared to PA, performing THA via DAA had a significantly higher surgeon stress index (17.4 versus 12.4; P < .001), heart rate (101 versus 98.3; P = .007), minute ventilation (21.7 versus 18.7; P < .001), and energy expenditure per hour (349 versus 295; P < .001). However, DAA had a significantly shorter operative time (71.4 versus 82.1; P = .001). CONCLUSIONS: Surgeons experience significantly higher physiological stress and strain when performing DAA compared to PA for primary THA. This study provides objective data on energy expenditure that can be factored into choice of approach, case order, and scheduling preferences, and provides insight into the work done by the surgeon.

The James A. Rand Young Investigator's Award: Keeping It Simple: Are all Musculoskeletal Infection Society Tests Useful to Diagnose Periprosthetic Joint Infection?

BACKGROUND: Current data evaluating the clinical value and cost-effectiveness of advanced diagnostic tests for periprosthetic joint infection (PJI) diagnosis, including alpha-defensin and synovial C-reactive protein (CRP), is conflicting. This study aimed to evaluate the adequacy of preoperative and intraoperative PJI workups without utilizing these tests. METHODS: This retrospective analysis identified all patients who underwent revision total knee or hip arthroplasty (rTKA and rTHA, respectively) for suspected PJI between 2018 and 2020 and had a minimum follow-up of 2 years. Perioperative data and lab results were collected, and cases were dichotomized based on whether they met the 2018 Musculoskeletal Infection Society (MSIS) criteria for PJI. In total, 204 rTKA and 158 rTHA cases suspected of PJI were reviewed. RESULTS: Nearly 100% of the cases were categorized as "infected" for meeting the 2018 MSIS criteria without utilization of alpha-defensin or synovial CRP (rTKA: n = 193, 94.6%; rTHA: n = 156, 98.7%). Most cases were classified as PJI preoperatively by meeting either the major MSIS or the combinational minor MSIS criteria of traditional lab tests (rTKA: n = 177, 86.8%; rTHA: n = 143, 90.5%). A subset of cases was classified as PJI by meeting combinational preoperative and intraoperative MSIS criteria (rTKA: 16, 7.8%; rTHA: 13, 8.2%). Only 3.6% of all cases were considered "inconclusive" using preoperative and intraoperative data. CONCLUSIONS: Given the high rate of cases satisfying PJI criteria during preoperative workup using our available tests, the synovial alpha-defensin and synovial CRP tests may not be necessary in the routine diagnostic workup of PJI. We suggest that the primary PJI workup process should be based on a stepwise algorithmic approach with the most economical testing necessary to determine a diagnosis first. The use of advanced, commercialized, and costly biomarkers should be utilized only when traditional testing is indeterminate.

Radiological Comparison of Canal Fill between Collared and Non-Collared Femoral Stems: A Two-Year Follow-Up after Total Hip Arthroplasty.

Collared femoral stems in total hip arthroplasty (THA) offer reduced subsidence and periprosthetic fractures but raise concerns about fit accuracy and stem sizing. This study compares collared and non-collared stems to assess the stem-canal fill ratio (CFR) and fixation indicators, aiming to guide implant selection and enhance THA outcomes. This retrospective single-center study examined primary THA patients who received Corail cementless stems between August 2015 and October 2020, with a minimum of two years of radiological follow-up. The study compared preoperative bone quality assessments, including the Dorr classification, the canal flare index (CFI), the morphological cortical index (MCI), and the canal bone ratio (CBR), as well as postoperative radiographic evaluations, such as the CFR and component fixation, between patients who received a collared or a non-collared femoral stem. The study analyzed 202 THAs, with 103 in the collared cohort and 99 in the non-collared cohort. Patients' demographics showed differences in age (p = 0.02) and ASA classification (p = 0.01) but similar preoperative bone quality between groups, as suggested by the Dorr classification (p = 0.15), CFI (p = 0.12), MCI (p = 0.26), and CBR (p = 0.50). At the two-year follow-up, femoral stem CFRs (p = 0.59 and p = 0.27) were comparable between collared and non-collared cohorts. Subsidence rates were almost doubled for non-collared patients (19.2 vs. 11.7%, p = 0.17), however, not to a level of clinical significance. The findings of this study show that both collared and non-collared Corail stems produce comparable outcomes in terms of the CFR and radiographic indicators for stem fixation. These findings reduce concerns about stem under-sizing and micro-motion in collared stems. While this study provides insights into the collar design debate in THA, further research remains necessary.

Perioperative Demographic and Laboratory Characteristics of Failed Debridement, Antibiotics, and Implant Retention: Can We Determine Which Patients Will Fail?

BACKGROUND: Debridement, antibiotics, and implant retention (DAIR) are the mainstays surgical treatment for acute periprosthetic joint infection (PJI). However, reoperation following DAIR is common and the risk factors for DAIR failure remain unclear. This study aimed to assess the perioperative characteristics of patients who failed initial DAIR treatment. METHODS: A retrospective review was conducted on 83 patients who underwent DAIR for acute PJI within 3 months following index surgery from 2011 to 2022, with a minimum one-year follow-up. Surgical outcomes were categorized using the Musculoskeletal Infection Society outcome reporting tool (Tiers 1 to 4). Patient demographics, laboratory data, and perioperative outcomes were compared between patients who had failed (Tiers 3 and 4) (n = 32) and successful (Tiers 1 and 2) (n = 51) DAIR treatment. Logistic regression was also performed. RESULTS: After logistic regression, Charlson Comorbidity Index (odds ratio [OR]: 1.57; P = .003), preoperative C-reactive protein (OR: 1.06; P = .014), synovial white blood cell (OR: 1.14; P = .008), and polymorphonuclear cell (PMN%) counts (OR: 1.05; P = .015) were independently associated with failed DAIR. Compared with total hip arthroplasty, total knee arthroplasty patients (OR: 6.08; P = .001) were at increased risk of DAIR failure. The type of organism and time from primary surgery were not correlated with DAIR failure. CONCLUSIONS: Patients who had failed initial DAIR tended to have significantly higher Charlson Comorbidity Index, C-reactive protein, synovial white blood cell, and PMN%. The total knee arthroplasty DAIRs were more likely to fail than the total hip arthroplasty DAIRs. These characteristics should be considered when planning acute PJI management, as certain patients may be at higher risk for DAIR failure and may benefit from other surgical treatments. LEVEL OF EVIDENCE: III.

Is It Getting More Expensive to Treat Patients Who Have a High Comorbidity Burden? Financial Trends in Total Knee Arthroplasty From 2013 to 2021.

BACKGROUND: Utilization of total knee arthroplasty (TKA) continues to rise among patients who have a high comorbidity burden (HCB). With changes in reimbursement models over the past decade, it is essential to assess the financial impact of HCB TKA on healthcare systems. This study aimed to examine trends in revenue and costs associated with TKA in HCB patients over time. METHODS: Of 14,978 TKA performed at a large, urban academic medical center between 2013 and 2021, we retrospectively analyzed HCB patients (Charlson comorbidity index ≥ 5 and American Society of Anesthesiology scores of 3 or 4). A total of 1,156 HCB TKA patients who had complete financial data were identified. Patient demographics, perioperative data, revenue, costs, and contribution margin were collected for each patient. Changes in these financial values over time, as a percentage of 2013 values, were analyzed. Linear regression was performed with a trend analysis to determine significance. RESULTS: From 2013 to 2021, the percentage of HCB TKAs per year increased from 4.2% in 2013 to 16.5% in 2021 (P < .001). The revenue of TKA in HCB patients remained steady (P = .093), while direct costs increased significantly (32.0%; P = .015), resulting in a decline of contribution margin to a low of 82.3% of 2013 margins. There was no significant change in rates of 90-day complications or home discharge following HCB TKA during the study period. CONCLUSIONS: The results of this study indicate a major rise in cost for TKA among HCB patients, without a corresponding rise in revenue. As more patients who have HCB become candidates for TKA, the negative financial impact on institutions should be considered, as payments to institutions do not adequately reflect patient complexity. A re-evaluation of institutional payments for medically complex TKA patients is warranted to maintain patient access among at-need populations.

Demographic and Socioeconomic Trends of Patients Undergoing Total Knee Arthroplasty From 2013 to 2022-An Analysis From an Urban Orthopaedic Hospital.

BACKGROUND: As worldwide utilization of total knee arthroplasty (TKA) broadens, demographic trends can help make projections to inform access to care. This study aimed to assess the temporal trends in the socioeconomic and medical demographics of patients undergoing TKA. METHODS: A retrospective review of 15,848 patients who underwent primary, elective TKA at an urban, New York City-based academic medical center between January 2013 and September 2022 was performed. Trends in patients' age, body mass index (BMI), socioeconomic status (SES) (based on median income by patients' ZIP code), race, and Charlson comorbidity index were evaluated using the Mann-Kendall test. RESULTS: In the last decade, mean patient age (65 to 68 years, P < .001) and Charlson comorbidity index (1.4 to 2.3, P < .001) increased significantly. The proportion of patients who had a BMI ≥ 30 and < 40 increased (43.8 to 51.2%, P = .002), while the proportion of patients who had a BMI ≥ 40 (13.7 to 12.1%, P = .015) and BMI < 30 (42.5 to 36.8%, P = .020) decreased. The distribution of patients' race and SES did not change from 2013 to 2022; Black (18.1 to 16.8%, P = .211) and low SES (12.9 to 11.3%, P = .283) patients consistently represented a minority of TKA patients. CONCLUSIONS: Over the last decade, the average age and comorbidity burden of TKA patients at our institution have increased. This portends the need for higher levels of preoperative optimization and postoperative management for TKA patients. A decreased prevalence of BMI ≥40 could reflect optimization efforts. However, the consistently low prevalence of Black and low-SES patients suggests that recent payment models did not improve access to care for these populations. LEVEL OF EVIDENCE: IV.

Simultaneous Versus Staged Bilateral Total Hip Arthroplasty: A Matched Cohort Analysis of Revenue and Contribution Margin.

BACKGROUND: Though previous studies have demonstrated improved cost benefits associated with simultaneous versus staged bilateral total hip arthroplasty (simBTHA and staBTHA), further investigation is needed regarding the revenues and contribution margins (CMs) of these procedures. In this study, we compared revenue, CM, and surgical outcomes between simBTHA and staBTHA. METHODS: All patients who underwent simBTHA (both procedures completed the same day) and staBTHA (procedures completed on different days within one year) between 2011 and 2021 at a single high-volume orthopedic specialty hospital were identified. Of the 1,517 identified patients (n = 139 simBTHA, n = 1,378 staBTHA), 232 were included in a 1:1 propensity match based on baseline demographics (116 per cohort). Revenue, costs, CM, and surgical outcomes were compared between cohorts. RESULTS: Compared to staBTHA, simBTHA procedures had significantly lower total costs (P < .001), direct costs (P < .001), and patient revenue. There was no significant difference in CM between groups (P = .361). Additionally, there were no significant differences in length of stay (P = .173), operative time (P = .438), 90-day readmissions (P = .701), 90-day revisions (P = .313), or all-cause revisions (P = .701) between cohorts. CONCLUSIONS: Though simBTHA procedures have lower revenues than staBTHA, they also have lower costs, resulting in similar CM between procedures. As both procedures have similar postoperative complication rates, further research is required to evaluate specifically which patients may benefit from simBTHA versus staBTHA regarding clinical and patient-reported outcomes. LEVEL OF EVIDENCE: III.

Trends in Revenue, Cost, and Contribution Margin of Patients Who Have a High Comorbidity Burden Undergoing Total Hip Arthroplasty From 2013 to 2021.

BACKGROUND: With the increasing utilization of total hip arthroplasty (THA) in patients who have a high comorbidity burden (HCB), coinciding with modifications to reimbursement models over the past decade, an evaluation of the financial impact of HCB on THA over time is warranted. This study aimed to investigate trends in revenue and cost associated with THA in HCB patients. METHODS: Of 13,439 patients who had primary, elective THA between 2013 and 2021 at our institution, we retrospectively reviewed 978 patients considered to have HCB (Charlson comorbidity index ≥ 5 and American Society of Anesthesiology scores 3 or 4). We collected patient demographics, perioperative data, revenue, cost, and contribution margin (CM) of the inpatient episode. We analyzed changes as a percentage of 2013 values over time for these financial markers. Linear regression determined trend significance. The final analysis included 978 HCB patients who had complete financial data. RESULTS: Between 2013 and 2021, direct costs increased significantly (P = .002), along with a nonsignificant increase in total costs (P = .056). While revenue remained steady during the study period (P = .486), the CM decreased markedly to 38.0% of 2013 values, although not statistically significant (P = .222). Rates of 90-day complications and home discharge remained steady throughout the study period. CONCLUSIONS: Increasing costs for HCB patients undergoing THA were not matched by an equivalent increase in revenue, leading to dwindling CMs throughout the past decade. Re-evaluation of reimbursement models for THA that account for patients' HCB may be necessary to preserve broad access to care. LEVEL OF EVIDENCE: III.

Increased patient body mass index is associated with increased surgeon physiologic stress during total hip arthroplasty.

INTRODUCTION: While increased body mass index (BMI) in patients undergoing total hip arthroplasty (THA) increases surgical complexity, there is a paucity of objective studies assessing the impact of patient BMI on the cardiovascular stress experienced by surgeons during THA. The aim of this study was to assess the impact of patient BMI on surgeon cardiovascular strain during THA. METHODS: We prospectively evaluated three fellowship-trained arthroplasty surgeons performing a total of 115 THAs. A smart-vest worn by the surgeons recorded mean heart rate, stress index (correlate of sympathetic activation), respiratory rate, minute ventilation, and energy expenditure throughout the procedures. Patient demographics as well as perioperative data including surgical approach, surgery duration, number of assistants, and the timing of the surgery during the day were collected. Linear regression was utilized to assess the impact of patient characteristics and perioperative data on cardiorespiratory metrics. RESULTS: Average surgeon heart rate, energy expenditure, and stress index during surgery were 98.50 beats/min, 309.49 cal/h, and 14.10, respectively. Higher patient BMI was significantly associated with increased hourly energy expenditure (P = 0.027), mean heart rate (P = 0.037), and stress index (P = 0.027) independent of surgical approach. Respiratory rate and minute ventilation were not associated with patient BMI. The number of assistants and time of surgery during the day did not impact cardiorespiratory strain on the surgeon. CONCLUSION: The physiologic burden on surgeons during primary THA significantly increases as patient BMI increases. This study suggests that healthcare systems should consider adjusting reimbursement models to account for increased surgeon workload due to obesity. Further surgeons should adopt strategies in operative planning and case scheduling to handle this added physical strain. LEVEL OF EVIDENCE: III.

Knotless suture in revision total joint arthroplasty: a prospective randomized controlled trial.

INTRODUCTION: The use of barbed sutures for wound closure in primary total joint arthroplasty (TJA) has been shown to be effective and safe. However, their effectiveness and safety in revision TJA procedures has not been thoroughly studied. This study aims to evaluate the efficacy and safety of using barbed suture closure in revision TJA setting. METHODS: A total of 80 patients undergoing revision TJA between September 2020 and November 2022 were included in this randomized controlled trial study. Following informed consent, patients were computer-randomized to the treatment arm (barbed suture wound closure) or to the control arm (conventional wound closure). Closure duration, closure rate, number of sutures used and wound related outcomes including complication rates and Patient and Observer Scar Assessment Scale (POSAS) score were compared between groups. RESULTS: The use of barbed sutures decreased closure time by 6 min (30.1 vs. 36.1 min, P = 0.008) with a higher wound closure rate (6.5 vs. 5.5 mm/minute, P = 0.013). Additionally, the number of sutures used for wound closure in the barbed group was significantly lower than in the control group (6.2 vs. 10.1, respectively, P < 0.001). There were no significant differences in the rate of postoperative wound complications (P = 0.556) or patient and observer POSAS scores (P = 0.211, P = 297, respectively) between the two groups at 3-month follow-up. CONCLUSION: Closure of revision TJA surgical wound utilizing barbed sutures reduced closure time and the number of needles handled by operative staff, with no significant increase in intra- or post-operative complications rate when compared to traditional closure technique. LEVEL OF EVIDENCE: I.

The Impact of Obesity on Total Hip Arthroplasty Outcomes When Performed by High-Volume Surgeons-A Propensity Matched Analysis From a High-Volume Urban Center.

BACKGROUND: Previous data suggest that obesity does not impact surgical outcomes following total knee arthroplasty performed by high-volume (HV) surgeons. However, this effect has yet to be studied in total hip arthroplasty (THA) patients. This study aimed to evaluate the impact of patient obesity on THA outcomes when surgery is performed by HV surgeons. METHODS: A retrospective analysis of patients who underwent primary, elective THA between January 2012 and December 2022 with a HV surgeon (top 25% of surgeons by number of annual primary THA) was performed. Patients were stratified by their body mass index (BMI) into 3 cohorts: BMI ≥ 40 (morbidly obese [MO]), 30 ≤ BMI < 40 (obese), and BMI < 30 (nonobese); and 1:1:1 propensity matched based on baseline characteristics. A total of 13,223 patients were evaluated, of which 669 patients were included in the final matched analysis (223 patients per group). The average number of annual THAs performed for HV surgeons was 171 cases. RESULTS: The MO patients had significantly longer surgical times (P < .001) and hospital lengths of stay (P < .001). Rates of 90-day readmissions (P = .211) and all-cause, septic, and aseptic revisions at the latest follow-up (P = .268, P = .903, and P = .168, respectively) were comparable between groups. In a subanalysis for non-HV surgeons, MO patients had a significantly greater risk of revision (P = .021) and trended toward significantly greater readmissions (P = .056). CONCLUSIONS: Clinical outcomes and complication rates after THA performed by a HV surgeon are similar regardless of patient obesity status. Patients who have MO may experience improved outcomes and reduced procedural risks if they are referred to HV surgeons. LEVEL OF EVIDENCE: III.

The Financial Burden of Patient Comorbidities on Total Hip Arthroplasties-A Matched Cohort Analysis of High Comorbidity Burden and Non-High Comorbidity Burden Patients.

BACKGROUND: The impact of increased patient comorbidities on the cost-effectiveness of total hip arthroplasty (THAs) is lacking. This study aimed to compare revenue, costs, and short-term (90 days) surgical outcomes between patients who have and do not have a high comorbidity burden (HCB). METHODS: We retrospectively reviewed 14,949 patients who underwent an elective, unilateral THA between 2012 and 2021. Patients were stratified into HCB (Charlson Comorbidity Index ≥ 5 and American Society of Anesthesiology scores of 3 or 4) and non-HCB groups, and were further 1:1 propensity matched based on baseline characteristics. Perioperative data, revenue, costs, and contribution margins (CMs) of the inpatient episode were compared between groups. Also, 90-day readmissions and revisions were compared between groups. Of the 11,717 patients who had available financial data (n = 1,017 HCB, n = 10,700 non-HCB), 1,914 patients were included in the final matched analyses (957 per group). RESULTS: Total (P < .001) and direct (P < .001) costs were significantly higher for HCB patients. Comparable revenue between cohorts (P = .083) resulted in a significantly decreased CM in the HCB patient group (P < .001). The HCB patients were less likely to be discharged home (P < .001) and had significantly higher 90-day readmission rates (P = .049). CONCLUSIONS: Increased THA costs for HCB patients were not matched by increased revenue, resulting in decreased CM. Higher rates of nonhome discharge and readmissions in the HCB population add to the additional financial burden. Adjustments to the current reimbursement models should better account for the increased financial burden of HCB patients undergoing THA and ensure access to care for all patient populations. LEVEL OF EVIDENCE: III.

Innovations in the Isolation and Treatment of Biofilms in Periprosthetic Joint Infection: A Comprehensive Review of Current and Emerging Therapies in Bone and Joint Infection Management.

Periprosthetic joint infections (PJIs) are a devastating complication of joint arthroplasty surgeries that are often complicated by biofilm formation. The development of biofilms makes PJI treatment challenging as they create a barrier against antibiotics and host immune responses. This review article provides an overview of the current understanding of biofilm formation, factors that contribute to their production, and the most common organisms involved in this process. This article focuses on the identification of biofilms, as well as current methodologies and emerging therapies in the management of biofilms in PJI.

Age as a Risk Factor for Intraoperative Periprosthetic Femoral Fractures in Cementless Hip Hemiarthroplasty for Femoral Neck Fractures: A Retrospective Analysis.

Background: Understanding the risk factors and outcomes of intraoperative periprosthetic femoral fractures (IPFF) during hip arthroplasty is crucial for appropriate perioperative management. Previous studies have identified risk factors for IPFF in total hip arthroplasty patients, but data for hip hemiarthroplasty (HA) is lacking. The aim of this study was to determine the age associated with increased rates of IPFF in patients undergoing HA. Methods: We retrospectively reviewed patients aged 65 years and above who underwent a cementless HA for a displaced femoral neck fracture and had a minimum of 1-year follow-up. Patients were stratified into five age groups (65-79, 80-84, 85-89, 90-94, and ≥ 95 years) and further divided into two subgroups (under 95 years and 95 years or older). The presence, location, and treatment of IPFF, as well as the effect of IPFF on the postoperative weight-bearing status, were compared between groups. A multivariate logistic regression was also performed. A total of 1,669 met the inclusion criteria and were included in the study. Results: The rates of IPFF were significantly higher for patients 95 years or older (p = 0.030). However, fracture location (greater trochanter fractures, p = 0.839; calcar fractures, p = 0.394; and femoral shaft fractures p = 0.110), intraoperative treatment (p = 0.424), and postoperative weight-bearing status (p = 0.229) were similar between the groups. While mortality and nonorthopedic-related readmissions were significantly higher for patients 95 years or older, orthopedic-related readmissions (p = 0.148) and revisions at the latest follow-up (p = 0.253) were comparable between groups. In a regression analysis, age over 95 years (odds ratio, 2.049; p = 0.049) and body mass index (odds ratio, 0.935; p = 0.016) were independently associated with IPFF. Conclusions: The findings of this study suggest that age over 95 years is a significant, independent risk factor for IPFF in patients undergoing cementless HA. Although we were unable to show an impact on perioperative outcomes and orthopedic complications, when operating on patients 95 years or older, surgeons should be aware of the increased risk of IPFF and consider the use of stem designs and fixation types associated with decreased IPFF rates.