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Replacement of lost cranial bone (partly mesodermal and partly neural crest‐derived) is challenging and includes the use of nonviable allografts. To revitalize allografts, bone marrow‐derived mesenchymal stromal cells (mesoderm‐derived BM‐MSCs) have been used with limited success. We hypothesize that coating of allografts with induced neural crest cell‐mesenchymal progenitor cells (iNCC‐MPCs) improves implant‐to‐bone integration in mouse cranial defects. Human induced pluripotent stem cells were reprogramed from dermal fibroblasts, differentiated to iNCCs and then to iNCC‐MPCs. BM‐MSCs were used as reference. Cells were labeled with luciferase (Luc2) and characterized for MSC consensus markers expression, differentiation, and risk of cellular transformation. A calvarial defect was created in non‐obese diabetic/severe combined immunodeficiency (NOD/SCID) mice and allografts were implanted, with or without cell coating. Bioluminescence imaging (BLI), microcomputed tomography (μCT), histology, immunofluorescence, and biomechanical tests were performed. Characterization of iNCC‐MPC‐Luc2 vs BM‐MSC‐Luc2 showed no difference in MSC markers expression and differentiation in vitro. In vivo, BLI indicated survival of both cell types for at least 8 weeks. At week 8, μCT analysis showed enhanced structural parameters in the iNCC‐MPC‐Luc2 group and increased bone volume in the BM‐MSC‐Luc2 group compared to controls. Histology demonstrated improved integration of iNCC‐MPC‐Luc2 allografts compared to BM‐MSC‐Luc2 group and controls. Human osteocalcin and collagen type 1 were detected at the allograft‐host interphase in cell‐seeded groups. The iNCC‐MPC‐Luc2 group also demonstrated improved biomechanical properties compared to BM‐MSC‐Luc2 implants and cell‐free controls. Our results show an improved integration of iNCC‐MPC‐Luc2‐coated allografts compared to BM‐MSC‐Luc2 and controls, suggesting the use of iNCC‐MPCs as potential cell source for cranial bone repair., Bone marrow‐derived mesenchymal stromal cells (BM‐MSCs) were obtained from human bone marrow. Induced neural crest cell‐mesenchymal progenitor cells (iNCC‐MPCs) were generated from induced pluripotent stem cell‐derived iNCCs. Cells were luciferase transfected and seeded onto decellularized allografts, which were implanted into 5 mm circular calvarial defects in non‐obese diabetic/severe combined immunodeficiency (NOD/SCID) mice. Allograft only was used as controls. Mice were followed for a duration of 8 weeks. Cell survival, allograft integration, and tissue morphology and transplanted cell contribution were monitored via bioluminescence imaging (BLI), micro‐computed tomography (μCT), and histology and immunofluorescence (IF). Green arrow: BLI; yellow arrow: μCT; Orange arrow: histology and IF; Blue arrow: biomechanical test.

This survey study investigates individuals' decision-making process for seeking emergency department treatment for conditions unrelated to COVID-19 during the COVID-19 pandemic using hypothetical scenarios., Key Points Question What do people prioritize when deciding whether to present to the emergency department during the COVID-19 pandemic for care unrelated to COVID-19? Findings In this survey study of 933 US adults, we found that 16.9% and 25.5% of individuals confronted with scenarios consistent with myocardial infarction or appendicitis, respectively, prioritized avoidance of COVID-19 exposure in the emergency department over seeking appropriate care. Sociodemographics, political affiliations, and personal knowledge, attitudes, and beliefs regarding COVID-19 were not factors associated with decision-making regarding emergency care seeking. Meaning These findings suggest that health care systems and public health organizations should develop effective communications for patients and the community at large that reassure and encourage appropriate, timely health care for critical needs, not only during the ongoing COVID-19 pandemic, but also for future infectious outbreaks and other scenarios that could promote maladaptive pathogen-avoidance behaviors., Importance Delaying critical care for treatable conditions owing to fear of contracting COVID-19 in the emergency department (ED) is associated with avoidable morbidity and mortality. Objective To assess and quantify how people decided whether to present to the ED during the COVID-19 pandemic for care unrelated to COVID-19 using conjoint analysis, a form of trade-off analysis that examines how individuals make complex decisions. Design, Setting, and Participants This cross-sectional survey study was conducted using a nationwide sample from June 1, 2020, during the initial peak of the COVID-19 pandemic. Included participants were adults aged 18 years or older in the US who self-reported that they had not tested positive for COVID-19. Data were analyzed from July 2020 through May 2021. Exposures Participants completed a self-administered online survey. Main Outcomes and Measures Using a choice-based conjoint analysis survey, the relative importance was assessed for the following attributes for individuals in deciding whether to seek ED care for symptoms consistent with myocardial infarction or appendicitis: reduction in chance of dying because of ED treatment, crowdedness of ED with other patients, and chance of contracting COVID-19 in the ED. We also performed latent class analyses using conjoint data to identify distinct segments of the respondent population with similar choice patterns. Logistic regression was then used to explore whether patient sociodemographics and political affiliations were factors associated with decision-making. Results Among 1981 individuals invited to participate, 933 respondents (47.1%) completed the survey; participants’ mean (SD) age was 40.1 (13.0) years, and 491 (52.6%) were women. In latent class analyses, 158 individuals (16.9%) with symptoms of myocardial infarction and 238 individuals (25.5%) with symptoms of appendicitis prioritized avoidance of COVID-19 exposure in the ED (ie, chance of contracting COVID-19 in the ED or crowdedness of ED with other patients) over seeking appropriate care for symptoms. Having a usual source of care was a factor associated with lower odds of prioritizing avoidance of COVID-19 exposure (myocardial infarction scenario: adjusted odds ratio, 0.49 [95% CI, 0.32-0.76]; P = .001; appendicitis scenario: adjusted odds ratio, 0.57 [95% CI, 0.40-0.82]; P = .003), but most sociodemographic factors and political affiliations were not factors associated with decision-making. Conclusions and Relevance This study found that up to one-quarter of individuals were willing to forgo potentially life-saving ED care to avoid exposure to COVID-19. These findings suggest that health care systems and public health organizations should develop effective communications for patients and the community at large that reassure and encourage timely health care for critical needs during the ongoing COVID-19 pandemic and other scenarios.

Background: Calcaneoplasty is a common procedure performed for the management of Haglund’s syndrome when nonoperative management fails. Midline tendon-splitting and endoscopy are 2 common approaches to calcaneoplasty. Studies have suggested that an endoscopic approach may allow earlier return to activity and superior outcomes, but there are no biomechanical or clinical studies to validate these claims. The goal of this study was to quantify and compare Achilles tendon pullout strength following midline tendon-splitting and endoscopic calcaneoplasty in cadaveric specimens. Methods: Twelve match-paired cadaveric specimens were randomly divided into 2 groups: endoscopic and midline tendon-split. Following calcaneoplasty, fluoroscopy was used to match bone resection and the Achilles was loaded to failure in a mechanical testing system. A paired-samples t test was conducted to compare bone resection height, bone resection angle, load to failure, and mode of failure. Results: The endoscopic approach yielded a 204% greater postsurgical pullout strength for the Achilles tendon than the midline tendon-split (1368 ± 370 N vs 450 ± 192 N, respectively) ( P < .05). There were no differences in resection angle or resection height. All specimens failed due to bone or tendon avulsion. Conclusion: Endoscopic calcaneoplasty had more than 3 times greater pullout strength than the midline tendon-splitting approach. Clinical Relevance: This may allow earlier return to functional rehabilitation following endoscopic calcaneoplasty, but further studies are needed to determine if these differences are clinically significant. Further understanding of the time-zero biomechanics following calcaneoplasty may provide guidance regarding postoperative management with respect to surgical approach.

Background Many patients with irritable bowel syndrome (IBS) experience acute and unexpected pain episodes over and above chronic background symptoms, and there are emerging medications designed to treat such pain. We aimed to use conjoint analysis-a technique that elucidates how people make complex decisions-to examine patient preferences for emerging medicines for breakthrough IBS pain. Methods We conducted a cross-sectional conjoint analysis survey among patients with Rome IV IBS and recurrent episodes of acute pain to assess the relative importance of medication attributes in their decision-making. We also assessed what respondents would require of subcutaneous (SQ) therapies to consider their use. Key results Among 629 patients with Rome IV IBS, 606 (96.3%) reported ≥1 acute pain episodes in the past month. For the 461 participants with multiple attacks who completed the conjoint analysis, they prioritized medication efficacy (importance score 34.9%), avoidance of nausea (24.3%), and avoidance of constipation (12.2%) as most important in their decision-making. These were followed by route of administration (10.3%), avoidance of headache (9.3%), and avoidance of drowsiness (8.9%). Moreover, 431 (93.5%) participants would consider SQ therapies for their acute pain; they had varying expectations on the minimum pain decrease and onset and duration of pain relief needed for considering their use. Conclusions and inferences The vast majority of patients with IBS experience breakthrough pain, and when selecting among therapies, they prioritize efficacy and most are willing to use a rapid-acting SQ treatment. These results support development of novel, effective medications-oral or SQ-for management of acute pain attacks.

Introduction Synthetic bone grafts are often used to achieve a well-consolidated fusion mass in spinal fusion procedures. These bone grafts function as scaffolds, and ideally support cell function and facilitate protein binding. Objective The aim was to characterize an electrospun, synthetic bone void filler (Reb) for its bone morphogenetic protein (BMP)-2 release properties and support of human mesenchymal stem cell (hMSC) function in vitro, and its efficacy in promoting BMP-2-/bone marrow aspirate-(BMA)-mediated posterolateral spinal fusion (PLF) in vivo. Methods BMP-2 release kinetics from Reb versus standard absorbable collagen sponge (ACS) was determined. hMSC adhesion and proliferation on Reb was tested using cell counting, fluorescence microscopy and MTS. Cell osteogenic differentiation was quantified via cellular alkaline phosphatase (ALP) activity. For in vivo analysis, 18 Lewis rats were treated during PLF surgery with the following groups: (I) Reb + BMA, (II) Reb + BMA + BMP-2 and (III) BMA. A safe, minimally effective dose of BMP-2 was used. Fusion consolidation was followed for 3 months using radiography and micro-CT. After sacrifice, fusion rate and biomechanical stiffness was determined using manual palpation, biomechanical tests and histology. Results In vitro, BMP-2 release kinetics were similar between Reb versus ACS. MSC proliferation and differentiation were increased in the presence of Reb. At 3 months post-surgery, fusion rates were 29% (group I), 100% (group II), and 0% (group III). Biomechanical stiffness was higher in group II versus I. Micro-CT showed an increased bone volume and connectivity density in group II. Trabecular thickness was increased in group I versus II. H&E staining showed newly formed bone in group II only. Conclusions Reb possesses a high protein binding affinity and promotes hMSC function. Combination with BMA and minimal dose BMP-2 allowed for 100% bone fusion in vivo. This data suggests that a minimally effective dose of BMP-2 can be used when combined with Reb.

Background: The flexor hallucis longus (FHL) and flexor digitorum longus (FDL) tendons are commonly used for tendon transfer in reconstructive foot and ankle procedures. Some patients experience great toe weakness and loss of push-off strength. The objective of this biomechanical study was to quantify plantarflexion force after FHL and FDL harvest and correlate it to variations in tendon crossover patterns at the knot of Henry to determine if specific patterns have an increased tendency toward forefoot weakness. Methods: Simulated loads through the Achilles, FHL, and FDL were applied to cadaveric specimens while plantarflexion force was measured using a pressure mapping system. Force was recorded with the FDL and FHL unloaded to simulate tendon transfer. Afterward, specimens were dissected to classify the tendinous slips between the FHL and FDL based on a previously determined system. Functional and anatomical relationships between the classification type and loading patterns were analyzed. Results: There were no statistical differences between the tendon crossover patterns in forefoot force reduction after FHL or FDL harvest. Average decrease in great toe and total forefoot pressure after FHL harvest was 31% and 22%, respectively. Average decrease in lesser toe and total forefoot push-off force after FDL harvest was 23% and 9%, respectively. Conclusion: This study quantified loss of plantarflexion force after simulated FHL and FDL harvest and correlated these losses to variations in anatomic crossover patterns at the knot of Henry. Variations at the knot of Henry do not contribute to differences in forefoot weakness. Clinical Relevance: The decrease in forefoot pressure seen here would help explain the clinical scenario where a patient does note a loss of great toe strength after FHL transfer.

Objectives: Hip microinstability is an increasingly recognized source of hip pain and disability. Femoral osteochondroplasty is usually performed with direct visualization through the arthroscope, assisted with repeated fluoroscopic view for orientation and feedback. However, a two-dimensional representation of a three dimensional structure can be misleading compromising the precision of the planned osteochondroplasty. Sometimes the resection can extend proximally into the Femoral Head (FH) diminishing the surface area of the articular cartilage available to be in contact with the labrum, in order to create the suction effect (suction seal) that maintains the stability of the femoral head in the acetabulum. The purpose of the study is to evaluate the role of proximal over-resection of femoral osteochondroplasty in the rotational and distractive stability of the hip joint. We hypothesis that proximal over resection will result in decrease stability, specially at higher degrees of flexion and internal rotation where the contact between labrum and articular cartilage will be lost, and breaking the suction seal. Methods: Six hemi-pelvises were repeatedly tested in the following five conditions: (a) intact, (b) T-capsulotomy, (c) Osteochondroplasty to the level of the physeal scar, followed by a (d) 5mm and (e) 10mm proximal extension of the resection. The pelvis was secured to a metal plate and the distal portion of the femur was potted and attached to a multi-axial hip jig. (Fig.1) Specimens were axially distracted with a load from 0-150N followed by 5Nm of internal and external torque at 0 o, 15 o, 30 o, 60 o, 90o of flexion while the resultant displacement/rotation was recorded using a 3D motion tracking system. Repeated measures ANOVA was used with statistical significance set at pResults: Proximal extension of the resection by 5mm and 10mm increased axial instability (decreased force required for hip distraction) at every angle of flexion tested, with the greatest increase observed at higher angles of flexion (60 deg and 90 deg), pConclusion: Extending the osteochondroplasty proximally into the femoral head compromised the distractive stability of the hip joint. It is important to be precise when performing femoral osteochondroplasty to minimize proximal extension that can lead to iatrogenic instability of the hip joint and poor postoperative outcomes. [Figure: see text][Figure: see text]

Category: Hindfoot Introduction/Purpose: The risk of Achilles avulsion is the limiting factor in return to full weight bearing and early activity following calcaneoplasty for Haglund’s syndrome. The most commonly performed surgical procedure is an open calcaneoplasty through a posterior approach. Another option is an endoscopic decompression, which theoretically causes less disruption of the Achilles insertion, and allows a more rapid return to full weight bearing and activity. Despite this potential benefit no study has assessed the difference in Achilles tendon pull-out strength after open versus endoscopic techniques. The purpose of this study was to investigate those changes in a cadaveric model and provide objective data upon which to base postoperative recovery. Methods: Six matched pairs of cadaveric specimens(mid-tibia to toes) were randomly divided into two surgical groups.Group#1 was treated with an endoscopic decompression under fluoroscopic guidance using a 4 mm burr.Group#2 was treated with a traditional calcaneoplasty through a posterior approach using a microsaggital saw.The Achilles was repaired back to the calcaneus with two nonsabsorbable suture anchors in Group #2.Fouroscopic guidance was used to exactly match the amount of bone removed from each matched pair.Pre and post procedure true lateral x-rays were obtained in both groups to quantify bone loss.These radiographic images were imported into Matlab computational software(MathWorks, Inc., Natick, MA) for digital analysis. The distal aspect of each calcaneus was potted and held at a 20 degree angle.The Achilles tendon was secured in a freeze-clamp, which was attached to a mechanical testing system. Specimens were then loaded to failure. Outcome measures include: Height of bony resection, angle of bone resection and load to failure. Results: To date our results show significantly higher pullout forces in specimens that had an endoscopic calcaneoplasty (average failure load: 1368 ±445 N) compared to those that received an open surgical procedure (450±184 N), pConclusion: This study describes the first biomechanical comparison of Achilles pull-out-strength between open and endoscopic calcaneoplasty.The endoscopic-technique had 204%greater pull-out-strength compared to the open-technique.Even though equal amounts of bone were resected in each technique, the open-technique requires more disruption of the Achilles insertion to accommodate the saw.This marked difference in pull-out-strength demonstrates the vulnerability of the Achilles insertion following open treatment.Our results support protected weight-bearing and cautious return to activity following open surgery. Also an endoscopic-technique results in significantly increased post-surgical mechanical strength compared to an open-technique. Therefore, earlier weight-bearing and return to activity may be warranted after endoscopic calcaneoplasty.