Matched-pair Study Research Articles

Music’s Influence on Cardiovascular Parameters During Cognitive Testing

BackgroundMozart’s music has been found to decrease stress and anxiety by decreasing blood pressure and heart rate in diverse populations. However, the influence on Mozart during cognitive tests remains unclear. Due to its proven anti-stress effects, Mozart’s music may be an effective tool for decreasing cardiovascular parameters during cognitive testing. MethodsThe cognitive test chosen was an untimed pattern-recognition Mensa test. The chosen song was Mozart’s Sonata K448. We included 10 adult participants who met the inclusion criteria. A matched pair study design was incorporated. All participants completed a diagnostic test that assessed relative cardiovascular sensitivities to the acute stress produced by the Mensa test. Participants were matched based on cardiovascular sensitivities, rating of momentary stress, and sex. Pairs were then randomly allocated to take the test again; one took the test while listening to Mozart’s Sonata K448, the other took it in silence. Post-test evaluations were then completed. ResultsIn both groups, the intervention did not induce significant changes in BP or HR, except for a significant decrease in SBP in the no music group (p=0.043). When comparing the difference in relative blood pressure and heart rate changes between the two groups, none were significantly different. There were significant decreases in perceived stress and increases in perceived relaxation in the music group (p=0.024 and p=0.039, respectively). ConclusionOur findings suggest that Mozart’s music does not decrease cardiovascular responses during cognitive testing. Additionally, perceived stress is independent of cardiovascular indicators of stress which has unknown implications.

Intensive Multiprofessional Rehabilitation Is Superior to Standard Orthogeriatric Care in Patients with Proximal Femur Fractures-A Matched Pair Study of 9580 Patients from the Registry for Geriatric Trauma (ATR-DGU).

Background: Orthogeriatric treatment, which involves a collaborative approach between orthopedic surgeons and geriatricians, is generally considered to be superior to standard care following hip fractures. The aim of this study was to investigate additional effects of a geriatrician-led multidisciplinary rehabilitation program. Methods: In this matched paired observational cohort study, patients aged 70 years and older with a proximal femur fracture requiring surgery were included. Between 1 January 2016 and 31 December 2022 data were recorded from hospital admission to 120-day follow-up in the Registry for Geriatric Trauma (ATR-DGU), a registry of older adults with hip fractures. Out of 60,254 patients, 9580 patients met the inclusion criteria, 4669 patients received early multiprofessional rehabilitation (EMR) and 4911 patients were treated by standard orthogeriatric co-management (OGC). Results: Compared to standard orthogeriatric treatment, multiprofessional therapy significantly lowered the 7-day mortality rate (2.89% vs. 5.11%) and had a significant impact on walking ability seven days after surgery (86.44% vs. 77.78%). Conclusions: In summary, a geriatrician-led multiprofessional rehabilitation program resulted in lower mortality and improved walking ability than standard orthogeriatric care.

Results of a large-scale humeri pair matching study.

During the analysis of a commingled human remains assemblage, pair-matching is often conducted as part of the inventory to inform the DNA sampling strategy and to calculate the minimum or most likely number of individuals. As commingled assemblages become larger, pair-matching becomes more difficult, and it is unknown whether accuracy declines. Therefore, a study to determine the accuracy rates of visual pair-matching for multiple observers was conducted on a large, commingled human assemblage. The sample consisted of 580 left and right humeri (n = 287 and n = 293, respectively) from the commingled remains of the USS Oklahoma, which were undergoing analysis at the Defense POW/MIA Accounting Agency. Five anthropologists completed this study, determining humeri pairs with varying degrees of confidence and non-pairs. The overall precision was 81.0% and ranged from 74.1% to 95.9% for participants, including all confidence levels. When considering only confident matches, the overall precision for all participants increased to 91.4%.

Long-term subjective and objective outcomes after digital nerve repair: a cohort study.

Digital nerve injuries are common, but few studies report long-term effects for the individual. The primary aim of this matched-pairs study comparing digital nerve injuries in border digits or central fingers was to investigate hand function 3-10 years after digital nerve repair, assessed using the Mini Sollerman test in 86 patients. Secondary outcomes were sensory function, range of motion, grip strength and patient-reported measures. No significant difference was seen in hand function between the groups, except for lower grip strength in patients with central finger injury. Tactile discrimination was achieved in 87%, with best results among participants aged less than 44 years. Touch perception was measurable in 99%. No statistically significant differences in sensory function were found between the groups. Patient-reported disability was low, with median Quick Disabilities of the Arm, Shoulder and Hand score of 5, but half of the patients reported neuropathic pain. Numbness and cold sensitivity were the symptoms graded worst after digital nerve injury.Level of evidence: III.

Comparative Survival Outcomes of Kidney Transplantation vs. Ongoing Dialysis in Extremely Elderly Patients: A Matched-Pair Study

Comparative Survival Outcomes of Kidney Transplantation vs. Ongoing Dialysis in Extremely Elderly Patients: A Matched-Pair Study

Individual cognitive empowerment and in-role performance: a matched-pair study.

The study examines the model fit of individual cognitive empowerment, which includes psychological and environmental factors, and investigates the direct effect of environmental empowerment specifically work methods, work criteria, and work schedules on in-role performance in Malaysia's Electrical and Electronic (E&E) manufacturing firms. Data were obtained from 173 engineers and 173 managers, matched in pairs, who have worked together for at least 1 year in 73 E&E manufacturing firms. The study found that the model fit of psychological and environmental factors is stronger for individual cognitive empowerment. Work methods show a positive direct effect on in-role performance. However, work schedules and work criteria do not appear to have a direct effect on in-role performance. This study highlights the importance of considering work methods in the engagement between engineer and manager pairs in the E&E manufacturing sector to enhance in-role performance.

Treatment outcomes of infertile women with endometrial hyperplasia undergoing their first IVF/ICSI cycle: A matched-pair study

ObjectiveThe aim was to analyze the clinical characteristics, controlled ovarian stimulation status, pregnancy outcomes, and major factors influencing live births in patients with endometrial hyperplasia (EH) undergoing IVF/ICSI for assisted reproduction, so as to identify potential intervention measures. Study designPatients with EH who achieved complete remission (CR) after conservative treatment and who were undergoing their first IVF/ICSI cycle were included in this matched-pair study. Patients with normal endometriums were matched at a 1:2 ratio with the control group for the first cycle of controlled ovarian stimulation. Matching was based on age, and reproductive outcomes were analyzed. ResultsAmong the 263 patients (including 51 cases with atypical endometrial hyperplasia) in the study group, the pregnancy rate after the first controlled ovarian stimulation cycle was 48.67 % (128/263), and the live birth rate was 34.98 % (92/263). Multiple logistic regression analysis revealed that maternal age, body mass index (BMI), and endometrial thickness were significantly associated with live births (P<0.001). Specifically, being aged ≥ 35 years (OR 0.450, 95 % CI 0.223–0.907) and having a BMI≥28 kg/m2 (OR 0.358, 95 % CI 0.161–0.798) were identified as unfavorable factors for a clinical live birth, while an endometrial thickness ≥ 10 mm was found to be a favorable factor. Conclusion(s)ART is effective in patients with EH who have achieved CR after conservative treatment. Avoiding unnecessary intrauterine procedures, controlling body weight appropriately, and choosing suitable ART methods as soon as possible may be beneficial for clinical outcomes.

Peri- and postoperative morbidity and mortality in older patients with non-small cell lung cancer: a matched-pair study

BackgroundReports from case series suggest that operative outcomes are comparable amongst different age groups following surgery with curative intent for non-small cell lung cancer (NSCLC). The purpose of this study was to compare morbidity and mortality after NSCLC surgery in older patients (≥ 75 years) versus younger patients (< 75 years) and identify independent predictive risk factors.MethodsWe identified 2015 patients with postoperative stages IA to IIIA according to AJCC/UICC 7th edition who had undergone NSCLC surgery with curative intent at a single specialized lung cancer center from January 2010 to December 2015. A matched-pair analysis was performed on 227 older patients and corresponding 227 younger patients. Short-term surgical outcomes were postoperative morbidity, length of hospital stay, 30-day and 90-day mortality. Long-term operative outcomes were disease-free and overall survival.Results454 patients were included in the matched-pair analysis. 36% of younger patients developed postoperative complications versus 42% in older patients (p = 0.163). Age was not significantly associated with the occurrence of postoperative complications. Median length of hospital stay was 14 days in older patients and 13 days in younger patients (p = 0.185). 90-day mortality was 2.2% in younger patients compared to 4% in older patients (p = 0.424). In patients aged 75 and older impaired performance status (ECOG ≥ 1) was associated with decreased overall survival (HR = 2.15, CI 1.34–3.46), as were preoperative serum C-reactive protein / albumin ratio ≥ 0.3 (HR = 1.95, CI 1.23–3.11) and elevated preoperative serum creatinine levels ≥ 1.1 mg/dl (HR = 1.84, CI 1.15–2.95). In the younger cohort male sex (HR = 2.26, CI 1.17–4.36), postoperative stage III disease (HR 4.61, CI 2.23–9.54) and preoperative anemia (hemoglobin < 12 g/dl) (HR 2.09, CI 1.10–3.96) were associated with decreased overall survival.ConclusionsLung resection for NSCLC in older patients is associated with postoperative morbidity and mortality comparable to those of younger patients. In older patients, physical activity, comorbidities and nutritional status are related to survival and should influence the indication for surgery rather than age alone.

Posterior Circulation Ischemic Stroke Is Associated with More Severe Forward Head Posture in Patients with Cervicalgia

Chronic risk factors of posterior circulation ischemic strokes remain unknown. There is, however, evidence that anatomical variations within the vertebrobasilar system could potentially lead to the development of posterior circulation strokes. We investigated the association of forward head posturing (FHP), a chronic anatomical change seen in patients with cervicalgia, with posterior circulation strokes. In this case-control study, we identified adult patients diagnosed with cervicalgia and ischemic posterior circulation infarcts from 2007 to 2023. Cases were paired with controls with cervicalgia without posterior circulation stroke and matched for known risk factors. C0-C2 angle, C2-C7 angle, and sagittal vertical axis shift were measured as metrics for FHP severity on lateral cervical spine x-rays. Paired t tests were applied to compare stroke risk factors and FHP between groups. Participants included 206 patients (103 cases and 103 controls) with a mean age of 64.4 years; 51.5% were female. There were no statistically significant differences between risk factors for stroke, including hypertension, hyperlipidemia, diabetes, smoking, hypercoagulable state, and atrial fibrillation. There were statistically significant differences in C0-C2 angle (30.7° vs. 23.2°, P=0.002) and sagittal vertical axis shift (35.4 mm vs. 25.3 mm, P < 0.001). This case-control matched-pair study found that in adults with cervicalgia, posterior circulation ischemic stroke was associated with more severe FHP as noted in C0-C2 angle and sagittal vertical axis shift measurements. Further, this association may be due to chronic changes in circulation flow dynamics within the vertebrobasilar system with the postural change.

Measuring cognitive effort using tabular transformer-based language models of electronic health record-based audit log action sequences.

To develop and validate a novel measure, action entropy, for assessing the cognitive effort associated with electronic health record (EHR)-based work activities. EHR-based audit logs of attending physicians and advanced practice providers (APPs) from four surgical intensive care units in 2019 were included. Neural language models (LMs) were trained and validated separately for attendings' and APPs' action sequences. Action entropy was calculated as the cross-entropy associated with the predicted probability of the next action, based on prior actions. To validate the measure, a matched pairs study was conducted to assess the difference in action entropy during known high cognitive effort scenarios, namely, attention switching between patients and to or from the EHR inbox. Sixty-five clinicians performing 5904429 EHR-based audit log actions on 8956 unique patients were included. All attention switching scenarios were associated with a higher action entropy compared to non-switching scenarios (P < .001), except for the from-inbox switching scenario among APPs. The highest difference among attendings was for the from-inbox attention switching: Action entropy was 1.288 (95% CI, 1.256-1.320) standard deviations (SDs) higher for switching compared to non-switching scenarios. For APPs, the highest difference was for the to-inbox switching, where action entropy was 2.354 (95% CI, 2.311-2.397) SDs higher for switching compared to non-switching scenarios. We developed a LM-based metric, action entropy, for assessing cognitive burden associated with EHR-based actions. The metric showed discriminant validity and statistical significance when evaluated against known situations of high cognitive effort (ie, attention switching). With additional validation, this metric can potentially be used as a screening tool for assessing behavioral action phenotypes that are associated with higher cognitive burden. An LM-based action entropy metric-relying on sequences of EHR actions-offers opportunities for assessing cognitive effort in EHR-based workflows.

Association of 5-aminolevulinic acid fluorescence guided resection with photodynamic therapy in recurrent glioblastoma: a matched cohort study.

Glioblastoma is a malignant and aggressive brain tumour that, although there have been improvements in the first line treatment, there is still no consensus regarding the best standard of care (SOC) upon its inevitable recurrence. There are novel adjuvant therapies that aim to improve local disease control. Nowadays, the association of intraoperative photodynamic therapy (PDT) immediately after a 5-aminolevulinic acid (5-ALA) fluorescence-guided resection (FGR) in malignant gliomas surgery has emerged as a potential and feasible strategy to increase the extent of safe resection and destroy residual tumour in the surgical cavity borders, respectively. To assess the survival rates and safety of the association of intraoperative PDT with 5-ALA FGR, in comparison with a 5-ALA FGR alone, in patients with recurrent glioblastoma. This article describes a matched-pair cohort study with two groups of patients submitted to 5-ALA FGR for recurrent glioblastoma. Group 1 was a prospective series of 11 consecutive cases submitted to 5-ALA FGR plus intraoperative PDT; group 2 was a historical series of 11 consecutive cases submitted to 5-ALA FGR alone. Age, sex, Karnofsky performance scale (KPS), 5-ALA post-resection status, T1-contrast-enhanced extent of resection (EOR), previous and post pathology, IDH (Isocitrate dehydrogenase), Ki67, previous and post treatment, brain magnetic resonance imaging (MRI) controls and surgical complications were documented. The Mantel-Cox test showed a significant difference between the survival rates (p = 0.008) of both groups. 4 postoperative complications occurred (36.6%) in each group. As of the last follow-up (January 2024), 7/11 patients in group 1, and 0/11 patients in group 2 were still alive. 6- and 12-months post-treatment, a survival proportion of 71,59% and 57,27% is expected in group 1, versus 45,45% and 9,09% in group 2, respectively. 6months post-treatment, a progression free survival (PFS) of 61,36% and 18,18% is expected in group 1 and group 2, respectively. The association of PDT immediately after 5-ALA FGR for recurrent malignant glioma seems to be associated with better survival without additional or severe morbidity. Despite the need for larger, randomized series, the proposed treatment is a feasible and safe addition to the reoperation.

A Meta-Analysis to Evaluate Implant Survival and Benefits of the Use of Dual Mobility Constructs in Total Hip Replacement Following Hip Fracture.

Total hip replacement (THR) is commonly performed to treat hip fractures. Dual-mobility constructs (DMCs) are increasingly used for this indication. The aimof this study was to use evidence synthesis techniques to estimate net all-cause construct survival for THR with DMC performed for hip fracture. Additionally, we aimed to investigate and describe differences in all-cause construct survival (if present) between THRs performed with DMC (DMC-THR) or with a conventional bearing construct following hip fracture. We performed a systematic review and meta-analysis of published studies (including joint registries), including DMC-THR for hip fracture which provided Kaplan-Meier (KM) survival estimates. The primary outcome was all-cause construct survival over time. The study was prospectively registered on PROSPERO (CRD42020173117). A total of 557 papers and 17 registry reports were identified. Six studies (four registry reports, one matched-pair cohort study utilising joint registry data, and one single-institution case series) met the inclusion criteria, including 17,370 DMC THRs and 167,377 conventional THRs. Five-year KM survival estimates (95% confidence intervals) were similar at 95.4% (94.9 to 95.8%) for DMC-THR and 96.2% (96.0 to 96.4%) for conventional THR. The relative risk of revision for DMC-THR at five years was 1.21 (1.05 to 1.41). These results suggest that DMC-THR has a lower all-cause survival than conventional THR following hip fracture. This analysis does not support the routine use of DMC-THR over conventional bearing THR.

Faster Bone Gap Union in Medial Opening Wedge High Tibial Osteotomy With 3D-Printed Synthetic Bioresorbable Polycaprolactone and Tricalcium Phosphate Osteotomy Gap Fillers Compared to Allogeneic Osteotomy Gap Fillers: A Retrospective Matched-Pair Cohort Study.

The use of synthetic bone substitute material (BSM) as osteotomy gap fillers have been reported to improve outcomes in medial opening wedge high tibial osteotomy (MOWHTO). This study aims to evaluate the early radiological outcomes (bone union) and complication rates of the novel patient-specific 3D-printed honeycomb-structured polycaprolactone and tricalcium phosphate (PCL-TCP) synthetic graft compared to allogeneic bone grafts as an osteotomy gap filler in MOWHTO. A retrospective matched-pair analysis of patients who underwent MOWHTO with either PCL-TCP synthetic graft or allogenic femoral head allograft as osteotomy gap filler was performed. The osteotomy gap was split into equal zones (Zone 1-5), and bone union was evaluated on anteroposterior radiographs based on the van Hemert classification at 1, 3, 6, and 12 months postoperatively. Postoperative complications including infection, lateral hinge fractures, and persistent pain was measured. The study and control group were matched for age, smoking status, diabetes mellitus, and osteotomy gap size. Significantly greater bone union progression was observed in the PCL-TCP group than in the allograft group at 1 month (Zones 1-3), 3 months (Zones 1-4), 6 months (Zones 1-2, 4), and 12 months (Zones 2-3, 5) postoperatively (P < 0.05). No significant difference in complications rates was noted between the two groups at 1 year. Bone union rates observed in patients who underwent MOWHTO with the PCL-TCP synthetic graft osteotomy gap filler were superior to those in the allograft group at 1 year postoperatively, with no significant difference in complication rates (postoperative infection, lateral hinge fractures, and persistent pain).

Influence of Concomitant Meniscal Allograft Transplantation on Midterm Outcomes After Osteochondral Allograft Transplantation: A Comparative Matched-Pair Analysis.

Osteochondral allograft transplantation (OCAT) is an accepted knee joint-preserving treatment strategy for focal osteochondral lesions that is often conducted in combination with meniscal allograft transplantation (MAT). Despite its frequent and simultaneous utilization, there remains a lack in the literature reporting on outcomes and failure rates after concomitant procedures. To determine (1) the midterm clinical success rate after OCAT+MAT in comparison with a matched-pair cohort undergoing isolated OCAT, (2) whether patient-specific and procedural variables influence the risk of failure, and (3) patient-reported outcome measures over time. Cohort study; Level of evidence, 3. A single-center matched-pair cohort study was conducted investigating outcomes in patients who underwent OCAT of the medial or lateral femoral condyle with and without MAT between 2004 and 2020. Patients were matched 1:1 by age (±5 years), sex (male or female), body mass index (±5), and grouped Kellgren and Lawrence grade (grades 0-1 or 2-4). The minimum follow-up time was 2 years. Radiographic variables (International Cartilage Regeneration & Joint Preservation Society [ICRS] grade and Kellgren and Lawrence grade) were assessed preoperatively and at follow-up. Subjective patient-reported outcome measures (Lysholm score, Knee injury and Osteoarthritis Outcome Score [KOOS] including subscores, International Knee Documentation Committee [IKDC] score, and visual analog scale score) were collected preoperatively and at follow-up. Clinical failure was defined as revision surgery for graft failure or conversion to total knee arthroplasty. Patient-reported, clinical, and radiographic outcomes were compared between groups. In total, 66 patients (33 treated with isolated OCAT, 33 treated with OCAT+MAT; 57.6% male) with a mean age of 26.3 years (range, 18-62 years) were followed for a mean of 5.6 years (minimum, 2 years; range, 24-218 months). The 2 cohorts showed no difference in Kellgren and Lawrence grade postoperatively (P = .59). There was a significantly higher ICRS grade detected at follow-up in the OCAT+MAT group (2.81 ± 1.10) compared with the OCAT group (2.04 ± 0.96) (P < .05). There were no statistically significant differences between the groups regarding reoperation rate (OCAT: n = 6; OCAT+MAT: n = 13; P = .116), time to reoperation (OCAT: 46.67 ± 47.27 months vs OCAT+MAT: 28.08 ± 30.16 months; P = .061), and failure rate (OCAT: n = 4 [12.1%] vs OCAT+MAT: n = 5 [15.2%]; P = .66). In the OCAT+MAT group, an increase of tibial slope by 1° conferred a 1.65-fold increase in the hazard for failure over decreased slope (hazard ratio, 1.65; 95% CI, 1.10-2.50; P < .05). The overall survival rate was 86% at a mean follow-up of 5.6 years. Patient-reported outcome scores were significantly improved at the final follow-up compared with preoperative status. No significant differences were seen between groups with respect to subjective IKDC, Lysholm, Tegner, and KOOS results, except for the KOOS Symptoms subscale score, which was significantly higher in the OCAT+MAT group than in the OCAT group (mean difference, 14.6; P < .05) and did exceed the minimal clinically important difference threshold of 10.7. Midterm results after isolated OCAT and OCAT+MAT show high rates of healing and sustainable subjective improvement of knee function and quality of life. However, it should be noted that the difference in reoperation rate and time to reoperation between the groups is arguably clinically important and that lack of statistical significance may be because of low power. These results imply that isolated OCAT is an efficient joint-preserving treatment that can be combined with MAT in well-selected patients with meniscal insufficiency without negative influence on global clinical outcomes.

Ectopic Pregnancy History as an Independent Factor Associated with Recurring Ectopic Pregnancy in Women with Bilateral Salpingectomies. A Matched-Pair Study of IVF Patients

Ectopic Pregnancy History as an Independent Factor Associated with Recurring Ectopic Pregnancy in Women with Bilateral Salpingectomies. A Matched-Pair Study of IVF Patients

Determinants of polycystic ovary syndrome: A matched case-control study.

Polycystic ovarian syndrome (PCOS) is a multifaceted endocrine disorder of women of reproductive age with a multifactorial aetiology. Despite much research, there is still inconclusive data on the impact of dietary, lifestyle and socio-economic factors on PCOS aetiology. Thus, the present study explored the association of PCOS with diet, eating behaviour, other lifestyle and socio-economic factors. A matched-pair case-control study was conducted on 150 women with PCOS and 150 healthy controls. Information on diet, eating behaviour and physical activity, and also anthropometric and socio-economic data were collected through standard questionnaires. The adjusted odds ratios (AmOR) were calculated and reported using conditional multivariable logistic regression. The results showed low education level (AmOR = 8.44; 95% confidence interval [CI] = 1.63-43.68), high sugar consumption (AmOR = 11.61; 95% CI = 2.05-65.72) along with higher body mass index (BMI) and inactivity to be significantly associated with PCOS. Also, a significant protective effect was found for cognitive dietary restraint (AmOR = 0.79; 95% CI = 0.66-0.93), crude fibre (AmOR = 0.61; 95% CI = 0.45-0.82) and protein intake. Low education status may contribute to higher receptiveness to choosing unhealthy diets and lifestyles, resulting in adiposity and an increased risk of PCOS.

Is there discrimination against children of same-sex households? Evidence from an experimental study in Colombia

We measure the extent of discrimination against homosexual parents by schools in Colombia using a matched-pair correspondence study. We send requests to visit private schools from parents of various sexual orientations as conveyed by their names. We track the response rate from schools and the time to reply. We find that schools are 12 percentage points (22.3 %) less likely to respond to a request sent by a homosexual couple than one sent by a heterosexual one. When no information about sexual orientation is provided, the response rate decreases by 20 pp. (37 %) compared to an explicitly heterosexual couple. Our findings suggest that, despite a solid legal framework that protects LGBTQ+ rights, discrimination against homosexual parents is pervasive and can have intergenerational consequences.

A matched-pair case control study identifying hemodynamic predictors of cerebral aneurysm growth using computational fluid dynamics.

Introduction: Initiation and progression of cerebral aneurysms is known to be driven by complex interactions between biological and hemodynamic factors, but the hemodynamic mechanism which drives aneurysm growth is unclear. We employed robust modeling and computational methods, including temporal and spatial convergence studies, to study hemodynamic characteristics of cerebral aneurysms and identify differences in these characteristics between growing and stable aneurysms. Methods: Eleven pairs of growing and non-growing cerebral aneurysms, matched in both size and location, were modeled from MRA and CTA images, then simulated using computational fluid dynamics (CFD). Key hemodynamic characteristics, including wall shear stress (WSS), oscillatory shear index (OSI), and portion of the aneurysm under low shear, were evaluated. Statistical analysis was then performed using paired Wilcoxon rank sum tests. Results: The portion of the aneurysm dome under 70% of the parent artery mean wall shear stress was higher in growing aneurysms than in stable aneurysms and had the highest significance among the tested metrics (p = 0.08). Other metrics of area under low shear had similar levels of significance. Discussion: These results align with previously observed hemodynamic trends in cerebral aneurysms, indicating a promising direction for future study of low shear area and aneurysm growth. We also found that mesh resolution significantly affected simulated WSS in cerebral aneurysms. This establishes that robust computational modeling methods are necessary for high fidelity results. Together, this work demonstrates that complex hemodynamics are at play within cerebral aneurysms, and robust modeling and simulation methods are needed to further study this topic.

Comparing two different placental transfusion strategies for very preterm infants at birth: a matched-pairs study

Objective To evaluate the clinical outcomes of using the extra-uterine placental transfusion (EPT) approach in very preterm infants (VPIs, gestational age <32 weeks) and compare this to delayed cord clamping (DCC) after birth. Methods In this matched pairs study, we compared the clinical outcomes of the EPT group to those of the DCC group. EPT were performed in fifty-three VPIs, of whom 27 were singletons and 25 were twins. The singleton VPIs were matched for gestational age (±5 days) and delivery mode, and the twin VPIs were matched between each other with the first twin subjected to DCC and the second twin to EPT. Data on the infants were collected and analysed as an overall group. A twin subgroup consisting of DCC and EPT groups was also analysed separately. The primary study outcome was either death or major morbidities. Results In total, 100 infants were included (n = 50 EPT group, n = 50 DCC group). The gestational ages of the DCC and EPT groups were (29.16 ± 1.76) and (29.12 ± 1.84) weeks, respectively. There were no differences in either deaths or major morbidities and other clinical outcomes, including the resuscitation variables, haemoglobin levels and red blood cell transfusion, between the two groups. In twin subgroups (gestational age 29.05 ± 1.89 weeks), EPT was associated with a higher rate of necrotizing enterocolitis (NEC) when compared with DCC (odds ratio = 7 (95% CI, 1.06 to 56.89), p = 0.031). Conclusions In twin subgroups, the incidence of NEC was higher in the EPT group when compared to the DCC group and therefore based on an abundance of caution the use of EPT in very preterm twins is not recommended.

LONG-TERM CLINICAL OUTCOMES AFTER SINGLE- VERSUS DOUBLE-BUNDLE ACL RECONSTRUCTION: A MATCHED-PAIR ANALYSIS FROM THE SANTI STUDY GROUP

IntroductionIt has been contentious whether an anatomic double-bundle technique for anterior cruciate ligament reconstruction (ACLR)is superior to that of a single-bundle technique. It has been hypothesized in the literature that the double-bundle technique could provide function closer to that of the anatomical knee joint. The purpose of this study was to compare the long-term clinical outcomes after single-bundle ACLR versus double-bundle ACLR. We hypothesized that the double-bundle technique would not be superior to the single-bundle technique.MethodsA retrospective, non-randomized, matched-paired comparative study was performed. Patients undergoing primary anterior cruciate ligament reconstruction, using either a double-bundle or single-bundle technique, between 2003 and 2008 were included and matched 1:1. Matching included age, sex, BMI, time from injury to surgery, side of injury and type of sport. Patients who underwent revision procedures, multiligament reconstruction or other ACLR techniques were excluded. Patients were subsequently followed up, noting occurrence of graft rupture and any other complications.ResultsA total of 1377 ACLRs were performed during the study period. Seven hundred and fifty-six patients were excluded, leaving 396patients to be included in the matching (198 matched pairs). Mean follow-up time was 176.7 +/− 7.7 months (range, 166–211 months). Overall, 40 patients (10.1%) suffered from a graft rupture which consisted of 22 patients (11.1%) in the single-bundle group and 18patients (9.1%) in the double-bundle group. A multivariate analysis was performed using the Cox model and demonstrated that graft failure had no significant association with the surgical technique (hazard ratio (HR), 0.857(0.457;1.609), p=0.6313). (Figure 1) Five patients (2.5%) in the single-bundle group and 7 patients (3.5%) in the double-bundle group underwent secondary surgery for cyclops syndrome(p=0.5637). Three patients (1.5%) in the single-bundle group and 2 patients (1.0%) in the double-bundle group underwent arthrolysis(p=0.6547). Seven patients (3.5%) in the single-bundle group underwent secondary meniscectomy compared to 6 patients (3.0%) in the double-bundle group (p=0.7630).ConclusionDouble-bundle ACLR is not superior to single-bundle ACLR at long-term follow up. Therefore, orthopaedic surgeons do not need to use a double-bundle technique when performing ACL reconstruction.For any figures or tables, please contact authors directly.