OBJECTIVE:Patients with psoriatic arthritis (PsA) experience higher postoperative complication rates after total hip or total knee arthroplasty (THA and TKA, respectively) than patients with osteoarthritis, but contributing factors to this risk are poorly defined. We examined clinical factors predicting postoperative complications to determine whether PsA-specific disease activity is associated with adverse events (AEs). METHODS:We conducted a prospective study of adults with PsA undergoing THA or TKA. Baseline assessments included demographics, BMI, Charlson Comorbidity Index (CCI), PsA disease activity measures, patient global assessment, medications, and patient-reported outcomes. Operative synovial tissue was assessed for inflammation. Postoperative AEs collected within 1 year were graded for severity (1-4) using the Clavien-Dindo (CD) classification. Logistic regression, adjusting for age and sex, assessed predictors of AEs and AE severity. RESULTS:In total, 57 patients were included (24 THA, 33 TKA). At surgery, patients had moderate PsA activity (mean Disease Activity Index for Psoriatic Arthritis [DAPSA] score of 15.8) with minimal skin disease or enthesitis. CD grade 3-4 AEs occurred in 10 patients (18%). BMI and CCI were higher in THA patients with any AEs and all patients with grade 3-4 AEs. In the adjusted analysis, higher CCI was associated with grade 2-4 and 3-4 AEs, and BMI with grade 3-4 AEs. No PsA-specific measures, including DAPSA or synovial histologic inflammation, were associated with AEs. CONCLUSION:In patients with PsA undergoing THA/TKA, AEs were driven by comorbidity burden and obesity rather than PsA-specific disease activity or joint inflammation. This finding highlights the importance of perioperative optimization of comorbidities and weight.

BACKGROUND:Systemic lupus erythematosus (SLE) patients seeking total knee arthroplasty (TKA) typically present with secondary osteonecrosis of the knee. Whether osteonecrosis negatively affects TKA outcomes in this high-risk population has not previously been studied. This study aimed to compare TKA survivorship, clinical outcomes, and postoperative complication rates between SLE patients who did and did not have osteonecrosis. METHODS:A retrospective analysis of SLE patients undergoing TKA between 2015 and 2023 at a large academic institution was conducted. The cohort was stratified by the presence of osteonecrosis on preoperative X-ray and magnetic resonance imaging when available. Imaging diagnosis was validated by an experienced musculoskeletal radiologist. Patient characteristics, clinical outcomes, and patient-reported outcome measures were compared between groups using univariable and multivariable analyses. We identified 179 knees in 147 patients who had lupus undergoing TKA. There were twelve percent (n = 21 of 179) of the knees that had osteonecrosis. The mean follow-up was 4.8 years (range, 1.0 to 9.1). RESULTS:Osteonecrosis was associated with younger age (P < 0.01) and lower body mass index (P = 0.04). Osteonecrosis was not a risk factor for postoperative readmission or revision, but younger age was associated with increased risk for both (P = 0.02 and P < 0.01, respectively). The 5-year TKA revision-free survivorship was 94.9% [95% confidence interval: 91.4 to 98.5] for all SLE patients and 95.2% [95% confidence interval: 86.6 to 100.0] for SLE with osteonecrosis. All patient-reported outcome measures improved from preoperative baseline (P < 0.01), irrespective of osteonecrosis. The magnetic resonance imaging patterns of osteonecrosis were categorized into three distinct types to guide surgical planning: (A) primarily meta-diaphyseal; (B) meta-diaphyseal with articular extension; and (C) severe deformity or bone loss. CONCLUSIONS:Osteonecrosis in SLE patients was not associated with worse TKA outcomes at a mean follow-up of five years. Longer-term durability of TKA in these patients requires further study.

Background:Orthopaedic consultations' influence on perceived barriers to total joint arthroplasty (TJA) remains unclear. This study explores how orthopedic consultations are associated with patient perceptions of barriers to TJA. Methods:We performed a post-hoc analysis of questionnaire responses based on data from a previous study that used semi-structured interviews with patients with advanced osteoarthritis. This earlier study identified 5 key barriers to TJA-trust in surgeon, cost/insurance, recovery, surgical outcome, and timing of surgery-and highlighted significant racial differences in these barriers. Our analysis focused specifically on the role of orthopaedic consultations. Using multiple logistic regression models, we compared responses from patients who had an orthopaedic consultation to those who did not, while adjusting for race, age, Hip Disability and Osteoarthritis Outcome Score, Joint Replacement/Knee Injury and Osteoarthritis Outcome Score, Joint Replacement, insurance status, education level, and prior discussions about TJA. Results:Of the 696 participants, 88% were female, 77% White, 11% Black, and 9% Hispanic. Nearly half (49%) had an orthopaedic consultation. Participants who had consulted with an orthopaedist were older, more likely to be college graduates, Medicare beneficiaries, have consulted a primary care physician, attempted conservative management including joint injections, braces, and physical therapy. After adjusting for participant factors, orthopaedic consultation was a predictor of fewer perceived cost/insurance and timing barriers. However, no differences were observed in other barriers. Conclusions:Orthopaedic consultation is associated with fewer reported cost/insurance and timing barriers to TJA. Addressing barriers of concern to patients in the context of orthopaedic consultations could further improve TJA utilization.

BACKGROUND:Juvenile idiopathic arthritis (JIA) is a rare disease that oftentimes requires treatment with total knee arthroplasty (TKA). Although studies have examined the outcomes of primary TKA for this cohort, the literature on 10- and 20-year revision TKA implant survivorship and clinical outcomes is limited. METHODS:A multicenter retrospective review identified 63 patients who underwent 70 revision TKAs between June 1, 1987, and September 30, 2020. The primary and secondary outcomes of interest were long-term implant survivorship and clinical outcomes, respectively. Patient-reported outcomes were assessed between April 1, 2020, and December 31, 2022. The average age was 47 years (range, 21 to 75). The mean follow-up was 12 years (range, 1.2 to 32.8) for both implant survivorship and patient-reported outcomes. RESULTS:Implant survivorship for revision TKA in JIA patients was 86% (95% confidence interval (CI): 77 to 94) at 5 years, 75% (95% CI: 65 to 86) at 10 years, and 70% (95% CI: 59 to 81) at 20 years. The mean Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) score was 72.8 ± 16.1 points, with 53% (18 of 34 patients, 21 of 38 TKAs) reaching the KOOS JR patient acceptable symptom state threshold. Risk factors for rerevision included the use of constrained prostheses (hazards ratio: 6.0, 95% CI [1.3 to 28.6], P = 0.025). The most common reasons for rerevision were implant loosening/instability (eight TKAs, 40%), pain/synovitis (eight TKAs, 40%), and infection (four TKAs, 20%). CONCLUSIONS:Revision TKA implant survivorship for JIA patients is modest at 10 and 20 years after surgery. Patient-reported outcomes were similar to those previously reported for revision TKA. Rerevision risk increased with higher levels of constraint. Surgeons should be aware of these outcomes and risk factors when counseling and treating these patients the second time around. LEVEL OF EVIDENCE:IV.

Background Patients who undergo total hip arthroplasty (THA) oftentimes have severe osteoarthritis in both hips and may consider staged or simultaneous bilateral THA (bTHA). The goal of this study was to compare the total workdays missed following staged and simultaneous bTHA performed via either postero-lateral (PA) or direct anterior approach (DAA). Methods Patients who were (1) employed, (2) underwent a staged (within 12 months) or simultaneous bTHA at our institution between February 1, 2016, and December 31, 2021, (3) completed a return-to-work questionnaire, and (4) had the same surgical approach for both THAs were included. The primary outcome of interest was the total days of work missed. Results We identified 78 employed patients who had undergone staged bTHA (62 PA, 16 DAA) and 76 patients (44 PA, 32 DAA) who underwent simultaneous bTHA, and had completed the return-to-work questionnaire. Simultaneous bTHA patients missed an average of 25.6 days of work (SD: 14.3 days) compared to staged bTHA patients, who missed an average of 36.9 days of work (SD: 23.4) when combining days missed from both operations (P < 0.001). In multivariate mixed regression analysis adjusted for sex, age, body mass index, American Society of Anesthesiologists status, type of work, and surgical approach, the staged bTHA group missed a mean of 8.2 more days of work (SD: 3.3) compared to the simultaneous bTHA group (95% confidence interval: 1.8 to 14.7, P = 0.013). Conclusions Employed patients who underwent simultaneous bTHA missed an average of 8.2 fewer days of work compared to those who were treated with staged bTHA. These findings may help surgeons counsel their employed patients who have bilateral hip osteoarthritis and are considering surgical treatment. Level of Evidence IV, retrospective cohort study.

Objective Diagnosis of periprosthetic joint infection (PJI) in patients with inflammatory arthritis (IA) is challenging, as features of IA flares can mimic infection. We aimed to cross-sectionally determine if the optimal tests to diagnose PJI in osteoarthritis were present in patients with IA flares. Methods We enrolled patients from October 2020 to July 2022 in 3 groups: (a) PJI—total joint arthroplasty patients undergoing revision for infection, (b) IA Flare—IA patients with a flaring native joint, and (c) IA Aseptic—total joint arthroplasty patients with IA undergoing aseptic arthroplasty revision. We compared blood and synovial fluid markers between the cohorts using Kruskal-Wallis and Fisher exact tests to assess marker sensitivity and specificity. Results Of 52 cases overall, 40% had rheumatoid arthritis, 20% psoriatic arthritis, and 11% osteoarthritis (in PJI group). PJI cases had higher C-reactive protein (CRP) and synovial fluid polymorphonuclear neutrophil percentage (%PMN). Alpha-defensin tested positive in 93% of PJI cases, 20% of IA Flares, and 6% of IA Aseptic (p < 0.01). Synovial white blood cell count >3000/μL and positive alpha-defensin were highly sensitive (100%) in diagnosing infection; however, specificity was 50% for white blood cell counts and 79% for alpha-defensin. PJI diagnosis was nearly 5 times more likely with positive alpha-defensin and almost 6 times more likely with %PMNs >80. Blood markers interleukin-6, procalcitonin, and d-dimer were neither sensitive nor specific, whereas erythrocyte sedimentation rate and CRP showed 80% sensitivity, but 47% and 58% respective specificities. Conclusions Although synovial %PMNs, CRP, and alpha-defensin are sensitive tests for diagnosing PJI, they are less specific and may be positive in IA flares.

Background Perioperative practices have been introduced over the last decade to decrease the risk of periprosthetic joint infection (PJI). We sought to determine whether rates of revision total knee arthroplasty (TKA) for PJI decreased during the period 2006-2016. Methods This observational cohort study used data from the New York Statewide Planning and Research Cooperative System to identify patients undergoing TKA in 2006-2016. Data through 2017 were used to determine if patients underwent revision TKA for PJI (including debridement, antibiotics and implant retention) within 1 year of the primary surgery. A generalized estimating equation model, clustered by hospital, was used to examine the impact of time on likelihood of revision TKA for PJI. Results In 2006-2016, 233,165 primary TKAs performed were included. Mean age was 66.1 (standard deviation 10.3) years, and 65% were women. Overall, 0.5% of the patients underwent revision TKA for PJI within 1 year of surgery. The generalized estimating equation model showed that for primary TKA performed in 2006-2013, year of surgery did not impact the likelihood of revision TKA for PJI (odds ratio 1.00, 95% confidence interval 0.97-1.03, P = .9221), but that for primary TKA performed in 2014-2016, the likelihood decreased by year (odds ratio 0.76, 95% confidence interval 0.66-0.88, P = .0002). Conclusions The likelihood of revision TKA for PJI was stable from 2006 to 2013 but declined during the period 2014-2016 across patient and hospital categories. This decline could be due to infection mitigation strategies or other unmeasured factors.

BACKGROUND:Patients who have bilateral hip arthritis can be treated with bilateral total hip arthroplasty (bTHA) in either a staged or simultaneous fashion. The goal of this study was to determine whether staged and simultaneous posterior bTHA patients differ in regard to (1) patient-reported outcome measures, (2) 90-day complication rates, and (3) discharge dispositions and cumulative lengths of stay. METHODS:Patients who (1) underwent simultaneous bTHA or staged bTHA (within 12 months) using the posterior approach, and (2) completed preoperative and 1-year postoperative Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement surveys were included in the study. A total of 266 patients (87 simultaneous bTHA and 179 staged bTHA) were included. Chart review was performed to collect patient-level variables, postoperative complications, discharge dispositions, and lengths of stay. RESULTS:Staged bTHA patients had higher Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement, Lower Extremity Activity Scale, and Veterans RAND 12-Item Health Survey physical component scores compared to simultaneous bTHA patients at 6 weeks after surgery (P = .019, .006, and .008, respectively), but these differences did not meet the minimal clinically important difference threshold for any questionnaire. Simultaneous bTHA was associated with higher rate of periprosthetic fractures (P = .034) and discharge to a location other than home (P < .001). CONCLUSIONS:There were statistically significant, but likely not clinically meaningful differences in patient-reported outcomes for staged and simultaneous bTHA patients at 6 weeks after surgery. Surgeons should be aware of the higher periprosthetic fracture risk and greater likelihood of discharge to a rehabilitation facility associated with simultaneous bTHA. Further research should aim to understand which patients may benefit most from simultaneous bTHA.

OBJECTIVE:Our aim was to determine the most significant barriers to total joint arthroplasty (TJA) for people living in high-poverty communities relative to low-poverty communities. METHODS:We created a 21-question survey based on interviews with underrepresented minority patients with osteoarthritis targeting five barriers to TJA: trust in surgeon, recovery concerns, cost and/or insurance issues, fear of poor surgical outcomes, and timing considerations. Participants rated the importance of each barrier on a 5-point Likert scale, dichotomized into "very or extremely important" and "not as important." The survey was distributed at New York City clinics and nationally through an arthritis advocacy group. We used geocoding to link addresses to census tracts, defining high-poverty communities as those with ≥20% of residents living below the poverty level. Logistic regression models assessed the association between community poverty status and rating barriers as very or extremely important, with adjustment for demographic and clinical factors. RESULTS:Of the 702 survey participants, 16.8% were residents of high-poverty communities. After adjustment, participants from high-poverty communities were more likely to rate trust in surgeon (adjusted odds ratio [aOR] 1.87, 95% confidence interval [CI] 1.24-2.82) and fear of poor surgical outcome (aOR 1.68, 95% CI 1.08-2.61) as very or extremely important. CONCLUSION:People from high-poverty communities identified lack of trust in surgeons and fear of poor surgical outcomes as more significant barriers to TJA compared to people from low-poverty communities.

Objective: Diagnosis of periprosthetic joint infection (PJI) in patients with inflammatory arthritis (IA) is challenging, as features of IA flares can mimic infection. We aimed to cross-sectionally determine if the optimal tests to diagnose PJI in osteoarthritis were present in patients with IA flares. Methods: We enrolled patients from October 2020 to July 2022 in 3 groups: (a) PJI-total joint arthroplasty patients undergoing revision for infection, (b) IA Flare-IA patients with a flaring native joint, and (c) IA Aseptic-total joint arthroplasty patients with IA undergoing aseptic arthroplasty revision. We compared blood and synovial fluid markers between the cohorts using Kruskal-Wallis and Fisher exact tests to assess marker sensitivity and specificity. Results: Of 52 cases overall, 40% had rheumatoid arthritis, 20% psoriatic arthritis, and 11% osteoarthritis (in PJI group). PJI cases had higher C-reactive protein (CRP) and synovial fluid polymorphonuclear neutrophil percentage (%PMN). Alpha-defensin tested positive in 93% of PJI cases, 20% of IA Flares, and 6% of IA Aseptic (p < 0.01). Synovial white blood cell count >3000/mu L and positive alpha-defensin were highly sensitive (100%) in diagnosing infection; however, specificity was 50% for white blood cell counts and 79% for alpha-defensin. PJI diagnosis was nearly 5 times more likely with positive alpha-defensin and almost 6 times more likely with %PMNs >80. Blood markers interleukin-6, procalcitonin, and d-dimer were neither sensitive nor specific, whereas erythrocyte sedimentation rate and CRP showed 80% sensitivity, but 47% and 58% respective specificities. Conclusions: Although synovial %PMNs, CRP, and alpha-defensin are sensitive tests for diagnosing PJI, they are less specific and may be positive in IA flares.

Aims: Implant waste during total hip arthroplasty (THA) represents a significant cost to the USA healthcare system. While studies have explored methods to improve THA cost-effectiveness, the literature comparing the proportions of implant waste by intraoperative technology used during THA is limited. The aims of this study were to: 1) examine whether the use of enabling technologies during THA results in a smaller proportion of wasted implants compared to navigation-guided and conventional manual THA; 2) determine the proportion of wasted implants by implant type; and 3) examine the effects of surgeon experience on rates of implant waste by technology used. Methods: We identified 104,420 implants either implanted or wasted during 18,329 primary THAs performed on 16,724 patients between January 2018 and June 2022 at our institution. THAs were separated by technology used: robotic-assisted (n = 4,171), imageless navigation (n = 6,887), and manual (n = 7,721). The primary outcome of interest was the rate of implant waste during primary THA. Results: Robotic-assisted THA resulted in a lower proportion (1.5%) of implant waste compared to navigation-guided THA (2.0%) and manual THA (1.9%) (all p < 0.001). Both navigated and manual THA were more likely to waste acetabular shells (odds ratio (OR) 4.5 vs 3.1) and polyethylene liners (OR 2.2 vs 2.0) compared to robotic-assisted THA after adjusting for demographic and perioperative factors, such as surgeon experience (p < 0.001). While implant waste decreased with increasing experience for procedures performed manually (p < 0.001) or with navigation (p < 0.001), waste rates for robotic-assisted THA did not differ based on surgical experience. Conclusion: Robotic-assisted THAs wasted a smaller proportion of acetabular shells and polyethylene liners than navigation-guided and manual THAs. Individual implant waste rates vary depending on the type of technology used intraoperatively. Future studies on implant waste during THA should examine reasons for non-implantation in order to better understand and develop methods for cost-saving. Cite this article: Bone Jt Open 2024;5(8):715–720.

Background: Patients with systemic lupus erythematosus (SLE) undergoing total hip arthroplasty and total knee arthroplasty (THA and TKA) experience higher complication rates than osteoarthritis (OA) patients. There are several molecular processes in SLE patients that may affect the response to the physiologic stresses of arthroplasty. Patients with SLE have been described to exhibit endothelial dysfunction, with excess secretion of soluble cell adhesion molecules, including intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), and these molecules are known to increase in plasma following arthroplasty. Excess Type 1 interferon (IFN) is a critical driver of SLE pathogenesis, and it may similarly affect the response to surgery as well as the postoperative healing process. We conducted a prospective study of SLE patients undergoing THA/TKA to investigate the role of these processes, performing comprehensive assessment of patients clinical and laboratory data, as well as biosample collection for assessment of endothelial cell dysfunction and IFN activity. Objectives: To characterize the degree of endothelial cell activation at baseline in SLE patients, as well as changes in this following THA/TKA by measuring plasma levels of soluble cell adhesion molecules ICAM-1 and VCAM-1. To characterize the difference in IFN activity in OA and SLE patients prior to and following THA/TKA. Methods: This prospective study enrolled 30 SLE patients with SLE satisfying either 2019 ACR/EULAR SLE classification criteria, or the 1997 modification of 1982 ACR SLE classification criteria. Additionally, 26 age-, sex-, and procedure-matched OA controls undergoing THA/TKA were enrolled. Demographics and risk stratification information was collected from all patients (BMI, medications, comorbidities, etc.). A rheumatologist (D.R.F., C.S.) evaluated SLE-specific disease activity on postoperative day 1 (POD1). Standard laboratory tests, as well as plasma and whole blood samples were collected from subjects at baseline, POD1, and six weeks postoperatively (6W). Plasma levels of soluble ICAM-1and VCAM-1 were measured, and whole blood RNA sequencing was performed from a subset of samples obtained at baseline, POD1, and 6W. Adverse events (AEs) were assessed at baseline, 1-, 6-, 12-, and 24-weeks. Descriptive statistics were performed and comparisons were made using Fisher's exact test, Chi-square and Wilcoxon rank-sum test. Results: The SLE patients in our cohort generally had low disease activity, with an average Systemic Lupus Erythematosus Disease Activity Index-2K score of 4, in keeping with a population undergoing elective surgery. SLE patients experienced significantly more postoperative anemia, and were seen in the emergency department more often in the 24 weeks postoperatively, compared with OA patients (Table 1). There were no significant differences in plasma levels of soluble ICAM-1 or VCAM-1 between OA and SLE patients (Table 2) at baseline or during the postoperative period. The IFN score and the IFN module identified on weighted correlation network analysis were significantly elevated in SLE patients at all time points. The IFN score and IFN module expression fell in all groups on POD1, before returning to levels comparable to baseline by 6W. A module with transcripts associated with B cells was identified, and was significantly lower in SLE patients versus OA controls at all time points. Conclusion: This is the first prospective analysis of SLE patients undergoing arthroplasty, proving the feasibility of such studies. No significant difference was observed in soluble cell adhesion molecules at any time point. Differential expression in B Cell and IFN modules was seen between OA and SLE patients, with dynamic shifts occurring in the immediate perioperative period. Larger prospective studies may allow for better assessment of factors associated with adverse events in SLE patients after THA/TKA. REFERENCES: NIL. Acknowledgements: We would like to thank and acknowledge the support of the HSS Surgeon-in-Chief research grant. Disclosure of Interests: David R. Fernandez: None declared, Stephen Batter: None declared, Deanna Jannat-Khah AstraZeneca, Cytodyn, Pfizer, Wallgreens, Mikhail Olferiev: None declared, Insa Mannstadt: None declared, Mark Figgie HS2, Joint Effort ASO, Mekanika, Wishbone, Lima, Wishbone, Peter Sculco DePuy, EOS Imaging, Intellijoint, Intellijoint, Parvizi Surgical Innovation, DePuy, EOS Imaging, Intellijoint, Lima Corporate, Zimmer, Intellijoint, Jason Blevins Globus Medical, KCI, Lima Corporate, Caroline Siegel: None declared, Dina Greenman: None declared, Kyriakos Kirou: None declared, Susan Goodman UCB, Norvartis.

Background: Little is known about patients’ postoperative week-by-week progress after undergoing posterior approach total hip arthroplasty (THA) with regard to pain, function, return to work, and driving. Purpose: We sought to evaluate a large cohort of patients undergoing posterior approach THA with modified posterior hip precautions to better understand the trajectory of recovery. Methods: Patients at a single institution undergoing primary posterior approach THA by fellowship-trained arthroplasty surgeons were prospectively enrolled. Patient functional status and early rehabilitation recovery milestones were evaluated preoperatively and each week postoperatively for 6 weeks. Results: Of 312 patients who responded to weekly questionnaires, there were varying response rates per question. At 1 week after surgery, 15% (39/256) of respondents had returned to work, increasing to 57% (129/225) at week 6. At 6 weeks, 77% of patients (174/225) had returned to driving; 25% (56/225) were taking pain medication (including prescription opioids or nonsteroidal anti-inflammatory drugs); and 15% (34/225) were using assistive devices (down from 91%, 78%, 56%, 35%, and 27% at weeks 1, 2, 3, 4, and 5, respectively). Average postoperative Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement and Lower Extremity Functional Scale scores were significantly higher than preoperative scores. Respondents reported significantly less pain at each week postoperatively than the previous week. Conclusion: These findings suggest that there may be an expected pathway for recovery after posterior THA using perioperative pain protocols, modified postoperative precautions, and physical therapy protocols to improve patient outcomes after THA, with most patients returning to normal at 4 weeks. Defining the expected recovery timeline may help surgeons in counseling patients preoperatively and guiding their recovery.

BACKGROUND:We sought to identify features that distinguish osteoarthritis (OA) and rheumatoid arthritis (RA) hematoxylin and eosin (H&E)-stained synovial tissue samples.METHODS:We compared fourteen pathologist-scored histology features and computer vision-quantified cell density (147 OA and 60 RA patients) in H&E-stained synovial tissue samples from total knee replacement (TKR) explants. A random forest model was trained using disease state (OA vs RA) as a classifier and histology features and/or computer vision-quantified cell density as inputs.RESULTS:Synovium from OA patients had increased mast cells and fibrosis (p < 0.001), while synovium from RA patients exhibited increased lymphocytic inflammation, lining hyperplasia, neutrophils, detritus, plasma cells, binucleate plasma cells, sub-lining giant cells, fibrin (all p < 0.001), Russell bodies (p = 0.019), and synovial lining giant cells (p = 0.003). Fourteen pathologist-scored features allowed for discrimination between OA and RA, producing a micro-averaged area under the receiver operating curve (micro-AUC) of 0.85±0.06. This discriminatory ability was comparable to that of computer vision cell density alone (micro-AUC = 0.87±0.04). Combining the pathologist scores with the cell density metric improved the discriminatory power of the model (micro-AUC = 0.92±0.06). The optimal cell density threshold to distinguish OA from RA synovium was 3400 cells/mm2, which yielded a sensitivity of 0.82 and specificity of 0.82.CONCLUSIONS:H&E-stained images of TKR explant synovium can be correctly classified as OA or RA in 82% of samples. Cell density greater than 3400 cells/mm2 and the presence of mast cells and fibrosis are the most important features for making this distinction.

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.

Background Health literacy is the ability to read and gain an understanding of health-related information, and make treatment and behavior choices accordingly. Poor health literacy is a main driver of health disparities in chronic medical conditions. Little is known about literacy in orthopedic surgery patients, which may be critical for post-surgical recovery. Objectives This study assessed health literacy in patients undergoing total knee arthroplasty (TKA) and its association with individual and community demographics, surgical length of stay (LOS), and discharge disposition. Methods The study population consisted of TKA patients at a single urban orthopedic specialty hospital from 2018-2021 who completed the health literacy screen. Health literacy, patient demographics and clinical variables were extracted from a data warehouse. Patient health literacy was defined by a validated single question tool (Morris et al. 2006) administered pre-operatively: “How often do you have someone like a family member, friend, hospital or clinic worker or caregiver help you read health plan materials, such as written information about your health or care you are offered?”. Answers were “Always”, “Often”, “Sometimes”, “Occasionally” or “Never”. “Always”, “Often”, or “Sometimes” answers reflect low health literacy and “Occasionally” or “Never” reflect adequate health literacy. Census-tract level measures of community poverty and education were obtained from the 2020 American Community Survey 5-year estimates. Variable comparisons were analyzed by χ2 and one-way analysis of variance (ANOVA), with p <0.05 considered statistically significant. Results 7,875 TKA patients were included. 81.3% had adequate health literacy and 18.7% had poor health literacy (Table 1). Poor health literacy patients were older (71 vs 69, p<0.0001) and spoke a non-English preferred language (7.2% vs 1.9%, p<0.0001). These patients had more comorbidities (Charlson score 2+, 92.1% vs 11.5%, p=0.001), longer LOS (hours, 58 vs 56, p<0.001), and were less often discharged to home (84.3% vs 87.8%, p=0.002). Multiple linear regression analysis using backwards elimination showed that LOS was associated with sex, comorbidity and discharge disposition, factors themselves also shown to be linked with health literacy. There were no differences in health literacy by ethnicity, insurance, community poverty or education levels. Conclusion We found that patients in our population with low health literacy were older, non-English speaking, of Asian/other race, had higher comorbidity scores and a lower proportion of home discharges than those with adequate health literacy. Thus health literacy screening can identify patient groups for whom interventions during the pre-surgical process can be targeted. Based on results, further study can examine whether tools to support health literacy may lead to impact on important measures such as LOS and discharge disposition in orthopedic surgery patients. Reference [1]Morris, N.S., MacLean, C.D., Chew, L.D. et al. The Single Item Literacy Screener: Evaluation of a brief instrument to identify limited reading ability. BMC Fam Pract 7, 21 (2006). Health services research, 45(4), 1105–1120. Acknowledgements: NIL. Disclosure of Interests None Declared.Table 1Significant characteristics of patient population by health literacy levelsVariable“Never”, “Occasionally” (Adequate health literacy) (n=6400)“Often”, “Sometimes”, “Always” (Low health literacy) (n=1475)p-valueAge, years (median [IQR])71.1 (9.6)74.8 (9.3)<0.0001Sex, female %3900 (60.9)900 (61)0.98Race, %<0.001White5211 (81.4)1201 (81.4)Black/African American540 (8.4)4 (3.3)Asian/Other649 (7.4)11 (9)Charlson comorbidity index0.00104220 (65.9)899 (60.9)11447 (22.6)386 (26.2)2+733 (11.5)1358 (92.1)Preferred language, %<0.0001English6278 (98.1)1368 (92.7)Spanish44 (0.7)27 (1.8)Other78 (1.2)80 (5.4)Surgical LOS, hours (median [IQR])56 [49, 79]58 [51, 81]<0.001Discharge disposition, %0.002Home687 (10.7)161 (10.9)Home with physical therapy4935 (77.1)1082 (73.4)Skilled nursing facility/Other778 (12.1)232 (15.7)

BACKGROUND:Lumbar spine pathology frequently coexists in patients who have hip arthrosis. There is controversy on whether lumbar or hip pathology should be first addressed. The purpose of this study was to evaluate the outcomes of sequential lumbar spine (LSP) or hip arthroplasty (THA). METHODS:Using a large national database from 2010 to 2020, we reviewed the records of 241,279 patients who had concurrent hip arthritis and lumbar spine disease defined as spinal stenosis, lumbar radiculopathy, or degenerative disc disease. During the study period, 6,458 (2.7%) patients with concurrent hip/spine disease underwent sequential operative treatment of either the hip joint or lumbar spine within 2 years. The rates of subsequent surgery in either the hip or the spine, opioid requirements, and rates of hip dislocation were determined and analyzed using compared Chi-squared analyses. RESULTS:Patients undergoing THA first had lower risk of subsequent spinal procedure compared to patients who had spinal procedures first (5.7 versus 23.7%, P < .001). This disparity was maintained up to 5 years (P < .001). Opioid requirements at 1 year were highest in patients who underwent spinal procedures only (836 pills/patient) compared to any other group THA only (566 pills/patient), LSP and then THA (564 pills/patient), THA and LSP (586 pills/patient). Also, THA following LSP was associated with significantly higher rates of dislocation compared to patients undergoing THA first (3.2 versus 1.9%, P < .001). CONCLUSION:Total hip arthroplasty first in patients who have concurrent spine disease was associated with lower risk of subsequent surgery, opioid requirement, and risk of postoperative instability compared to patients having lumbar procedure first.