Fetal bradycardia in open versus fetoscopic prenatal repair of spina bifida.

OBJECTIVE: To compare the occurrence of fetal bradycardia in open versus fetoscopic fetal spina bifida surgery. METHODS: This is a single-institution retrospective cohort study of patients undergoing open (n = 25) or fetoscopic (n = 26) spina bifida repair between 2017 and 2022. From October 2017 to June 2020, spina bifida repairs were performed via an open classical hysterotomy, and from November 2020 to June 2022 fetoscopic repairs were performed following transition to this technique. Fetal heart rate (FHR) in beats per minute (bpm) was recorded via echocardiography every 15 min during the procedure. Cohort characteristics, fetal bradycardia and maternal physiologic parameters were compared between the groups. RESULTS: Fetuses undergoing an open repair more frequently developed bradycardia defined as <110 bpm (32% vs. 3.8%, p = 0.008), and a trend was observed for FHR decreases more than 25 bpm from baseline (20% vs. 3.8%, p = 0.073). Profound bradycardia less than 80 bpm was rare, occurring in only three operations (two in open, one in fetoscopic repair) with two fetuses (one in each group) requiring emergency cesarean delivery. CONCLUSION: When compared to open fetal surgery, fetal bradycardia occurred less frequently in fetoscopic surgery despite a significantly greater anesthetic exposure and the use of the intraamniotic carbon dioxide insufflation.

Needle Fetal Thoracoscopy: A Technique to Assist with Ultrasound-Guided Placement of Challenging Thoracoamniotic Shunts.

INTRODUCTION: Fetal thoracoamniotic shunts are common lifesaving interventions but frequently require replacement. Needle fetal thoracoscopy is a technique that uses standard thoracoamniotic shunt introducer sheaths to permit direct visualization and even instrument manipulation during shunt deployment to facilitate optimal positioning and primary shunt function in the most challenging cases. CASE PRESENTATION: In this study, 5 patients who underwent needle fetal thoracoscopy-assisted thoracoamniotic shunt placement were reviewed. Three patients with large, macrocystic congenital pulmonary airway malformations (CPAMs) with evidence of worsening mediastinal shift and/or hydrops and 2 patients with large chylothorax with fetal hydrops were treated. Four cases had previous shunts that failed due to poor sonographic visualization during initial placement, cyst septations, shunt obstruction, or dislodgment. Needle fetal thoracoscopy was used to disrupt cyst walls and septations, clear hematoma, and confirm the optimal initial position of the shunt. In this series, 1 severe CPAM patient with a short cervix developed preterm labor postoperatively resulting in neonatal demise. The remaining 4 patients experienced resolution of hydrops and progressed to successful delivery with excellent neonatal outcomes. CONCLUSION: Needle fetal thoracoscopy is a procedure that may be selectively deployed in challenging thoracoamniotic shunt cases impacted by recurrent failure, poor sonographic windows, and challenging fetal positioning.

Management of undifferentiated embryonal sarcoma of the liver: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: Undifferentiated embryonal sarcoma of the liver (UESL) is a rare tumor for which there are few evidence-based guidelines. The aim of this study was to define current management strategies and outcomes for these patients using a multi-institutional dataset curated by the Pediatric Surgical Oncology Research Collaborative. METHODS: Data were collected retrospectively for patients with UESL treated across 17 children's hospitals in North America from 1989 to 2019. Factors analyzed included patient and tumor characteristics, PRETEXT group, operative details, and neoadjuvant/adjuvant regimens. Event-free and overall survival (EFS, OS) were the primary and secondary outcomes, respectively. RESULTS: Seventy-eight patients were identified with a median age of 9.9 years [interquartile range [IQR): 7-12]. Twenty-seven patients underwent resection at diagnosis, and 47 patients underwent delayed resection, including eight liver transplants. Neoadjuvant chemotherapy led to a median change in maximum tumor diameter of 1.6 cm [IQR: 0.0-4.4] and greater than 90% tumor necrosis in 79% of the patients undergoing delayed resection. R0 resections were accomplished in 63 patients (81%). Univariate analysis found that metastatic disease impacted OS, and completeness of resection impacted both EFS and OS, while multivariate analysis revealed that R0 resection was associated with decreased expected hazards of experiencing an event [hazard ratio (HR): 0.14, 95% confidence interval (CI): 0.04-0.6]. At a median follow-up of 4 years [IQR: 2-8], the EFS was 70.0% [95% CI: 60%-82%] and OS was 83% [95% CI: 75%-93%]. CONCLUSION: Complete resection is associated with improved survival for patients with UESL. Neoadjuvant chemotherapy causes minimal radiographic response, but significant tumor necrosis.

Ex-Utero Intrapartum Treatment-to-Airway for Obstructing Fetal Neck Masses: A Singular Methodology for Monochorionic and Dichorionic Twin Pregnancies.

Fetal airway obstruction in one twin of a diamniotic pregnancy presents unique challenges. Very few cases of ex-utero-intrapartum-treatment (EXIT) procedures for twin pregnancy have been reported and only in dichorionic pregnancies. We report a singular methodology for EXIT-to-airway procedures in two pregnancies involving monochorionic and dichorionic twins. Two cases of EXIT-to-airway in twin pregnancies were performed in 2018 and 2019 at a regional fetal treatment center. Case 1 involved a giant cervical teratoma in a monochorionic-diamniotic twin pregnancy with preterm labor at 29 weeks. Case 2 involved a dichorionic-diamniotic pregnancy with a large cervical lymphatic malformation with preterm labor at 36 weeks. In each case, the polyhydramnios caused the affected twin's amniotic sac to be the presenting sac for the surgical approach. Bronchoscopy and successful intubation was completed after 22 and 10 minutes of uteroplacental bypass, respectively. The bystander twins were delivered second without intubation and resuscitated without perinatal distress. EXIT-to-airway appears to be a reasonable option for twins including monochorionic pregnancies, via delivery of the affected twin first followed by delivery of the bystander twin. Thoughtful preparation and counseling by an experienced multidisciplinary team permits an EXIT-to-airway approach for twin pregnancies even in an emergent setting.

Measuring the Efficacy of Thymectomy for Pediatric Myasthenia Gravis Across Tertiary Children's Hospitals.

BACKGROUND: Thymectomy is a treatment for pediatric myasthenia gravis, but the efficacy over time is unknown. Multi-institutional data are also lacking. Therefore, the objective of this study was to determine the efficacy of thymectomy for pediatric myasthenia gravis using medication burden and health care utilization as proxies for disease severity. METHODS: This was a cross-sectional study of the Pediatric Health Information System database among children who underwent thymectomy at one of 49 children's hospitals from 2004 to 2022. Differences in annual median number of doses of myasthenia-related medications, admissions, and health care costs in the year before thymectomy to three years after were compared. A comparison cohort that did not undergo thymectomy was utilized. Medians were compared using the Wilcoxon signed-rank test. Generalized linear regression estimated the effect of surgical approach on outcomes. RESULTS: A total of451 patients (238 patients who underwent thymectomy and 213 nonthymectomy patients) were identified. Following thymectomy, the decrease in annual median total number of myasthenia-related doses was 12.0 (interquartile range: 6 to 31) (P < 0.001). The decrease in number of annual admissions was 2.0 (1 to 4) (P < 0.001), which represented a cost difference of $5292 ($3533 to $8681) (P < 0.001). No differences were observed in the control cohort. In a generalized linear regression model, surgical approach was not associated with the efficacy of thymectomy (P = 0.55). CONCLUSIONS: Thymectomy is an effective treatment for pediatric myasthenia gravis, evidenced by the decreased medication burden and health care utilization after surgery. Surgical approach did not influence the success of surgery. Thymectomy should be considered earlier in the treatment algorithm.

Nonparasitic Splenic Cysts in Children: Outcomes after Sclerotherapy or Surgical Resection as Initial Management.

Management of splenic cysts in children remains undefined. Sclerotherapy is an innovative, less invasive treatment. This study examined the safety and preliminary effectiveness of sclerotherapy for splenic cysts in children compared with those of surgical treatment. A retrospective review of pediatric patients treated for nonparasitic splenic cysts from 2007 to 2021 was performed at a single institution. Posttreatment outcomes for patients who underwent either expectant management, sclerotherapy, or surgery were reviewed. Thirty patients aged between 0 and 18 years met the inclusion criteria. Cysts in 3 of 8 patients who underwent sclerotherapy were either unresolved or recurred. Patients who underwent sclerotherapy and required surgery for residual symptomatic cyst had an initial cyst diameter of >8 cm. Symptoms resolved in 5 of 8 patients who underwent sclerotherapy, with a significantly reduced cyst size compared with that in patients with continued symptoms who underwent sclerotherapy (61.4% vs 7.0%, P = .01). Sclerotherapy is an effective treatment for splenic cysts, particularly those measuring <8 cm. However, surgical excision may be preferable for large cysts.

CD4 and IL-2 mediated NK cell responses after COVID-19 infection and mRNA vaccination in adults.

A detailed understanding of protective immunity against SARS-CoV-2 is incredibly important in fighting the pandemic. Central to protective immunity is the ability of the immune system to recall previous exposures. Although antibody and T cell immunity have gained considerable attention, the contribution of the NK cell compartment to immune recall and protection from SARS-CoV-2 has not been explored. In this study, we investigate the NK cell responses to stimulation with SARS-CoV-2 in previously exposed and non-exposed individuals. We show that NK cells demonstrate an enhanced CD4+ T cell dependent response when re-exposed to SARS-CoV-2 antigen. The enhanced response is dependent on T cells and correlates with the number of SARS-CoV-2 specific CD4 T cells. We find that IL-2 is a critical mediator of NK cell function. These findings suggest that NK cells contribute to the protective responses against SARS-CoV-2 through a cooperation with antigen-specific CD4 T cells and have significant implications on our understanding of protective immunity in SARS-CoV-2.

Expedited Surgical Care of Appendicitis is Associated With Improved Resource Utilization.

INTRODUCTION: Appendectomy for acute appendicitis is the most common pediatric intra-abdominal operation. Current literature supports the notion that modest in-hospital, preoperative delays are not associated with greater patient morbidity. However, there is less certainty regarding the role that hour-of-presentation plays in determining the timing of surgery. Thus, we aimed to evaluate how after-hours presentation may relate to the timing of surgery and to assess the outcomes and resource utilization associated with expedited appendectomy compared to nonexpedited. METHODS: Patient records for children who underwent an appendectomy at a freestanding pediatric hospital from 2015 to 2019 were reviewed. Business hour presentations were defined as arrival at the emergency department from 7 AM to 6 PM. Primary outcomes were hospital length of stay (LOS), cost derived from the Pediatric Health Information System database, perforation, surgical complications, and 30-day readmissions. RESULTS: Nine hundred forty-two patients underwent appendectomy over the study period. The median time to OR was 2.0 h in the expedited cohort and 9.8 h in the nonexpedited group. Presentation during business hours was associated with 4.4 higher odds (P < 0.001) of expedited workflow. Expedited appendectomies were associated with shorter hospital LOS (11.5 h, P < 0.001), less costly admissions ($1,155, P < 0.001); LOS measured in midnights, perforation and readmission rates were similar between groups. CONCLUSIONS: We found reduced resource utilization associated with expedited appendectomy. Additionally, the demonstrated association between the time of presentation to the emergency department (ED) and the timing of surgery may be utilized to inform staffing and resource deployment decisions. Further research regarding the generalizability and sustainability of an expedited presurgical workflow in pediatric appendectomy is certainly indicated.

The interplay between prenatal liver growth and lung development in congenital diaphragmatic hernia.

Objective: Liver herniation is a known risk factor for increased severity in CDH and is associated with clinically significant pulmonary hypoplasia and pulmonary hypertension. Better studies are needed to understand the growth of the herniated liver compared to the liver that remains in the abdomen and how this liver growth then affects lung development. Serial hi-resolution fetal MRI enables characterization of liver growth throughout gestation and examination of macroscopic features that may regulate liver growth. Here, we hypothesized that the nature of liver herniation affects liver growth and, in turn, affects lung growth. Methods: Clinical data were retrospectively collected from consecutive cases of prenatally diagnosed isolated left-sided or right-sided CDH from June 2006 to August 2021. Only those cases with MRI lung volumetry for both mid-gestation and late-gestation time points were recruited for analysis. Cases with fetal chromosomal abnormalities and other major structural abnormalities were excluded. Fractional liver volume and liver growth was indexed to estimated fetal weight and compared to lung growth. Results: Data was collected from 28 fetuses with a left liver-down CDH (LLD), 37 left liver-up CDH (LLU) and 9 right liver-up CDH (RLU). Overall, RLU fetuses had greater overall and fractional (intra-thoracic vs. intra-abdominal) liver growth when compared to LLD and LLU fetuses. Additionally, intra-thoracic liver growth was consistently slower than intra-abdominal liver growth for either right- or left-sided CDH. When the liver was not herniated, a positive correlation was seen between liver growth and lung growth. However, when the liver was herniated above the diaphragm, this positive correlation was lost. Conclusion: Right-sided CDH fetuses exhibit greater liver growth compared to left-sided CDH. Liver herniation disrupts the normal positive correlation between liver and lung growth that is seen when the liver is entirely within the abdomen.

The costs and benefits of emergent surgical workflow for acute appendicitis in children.

BACKGROUND: Controversy exists regarding how operative timing affects patient safety and resource utilization for acute appendicitis. Over 3 years, our institution trialed efforts to optimize appendectomy workflow. Our aim is to describe the ramifications of expediting appendectomy and implementing standardized protocols relative to historic controls. METHODS: Patient records at a freestanding children's hospital were reviewed from synchronized 6-month periods from 2019 to 2021. During Year 1 (historic), no standardized workflows existed. In Year 2 (expedited), appendicitis management was protocoled using a clinical quality improvement bundle, which included performing appendectomies within two hours of diagnosis. In Year 3 (QI), operative timing was relaxed to the same calendar day while all prior QI initiatives continued. Descriptive statistics were performed, using hospital length of stay (LOS) as the primary outcome. RESULTS: 298 patients underwent appendectomy for acute appendicitis. The median expedited workflow LOS was 15.3 hours shorter (p = 0.003) than historic controls; however, this was sustained despite relaxation of surgical urgency in the QI workflow. No differences in perforation rates were observed. During the expedited workflow, OR overtime staffing expense increased by $90,000 with no significant change in hospital costs. In multivariate regression, perforation was the only variable associated with LOS. CONCLUSION: Hospital LOS can be shortened by expediting appendectomy. However, in our institution this did not decrease hospital costs and was furthermore balanced by higher personnel expenses. A sustained decrease in LOS after relaxing operative urgency standards implies that concurrent QI initiatives represent a more effective and cost-efficient strategy to decrease hospital resource utilization. LEVEL OF EVIDENCE: Level III.

Histologic type predicts disparate outcomes in pediatric hepatocellular neoplasms: A Pediatric Surgical Oncology Research Collaborative study.

BACKGROUND: Hepatocellular carcinoma (HCC) is a rare cancer in children, with various histologic subtypes and a paucity of data to guide clinical management and predict prognosis. METHODS: A multi-institutional review of children with hepatocellular neoplasms was performed, including demographic, staging, treatment, and outcomes data. Patients were categorized as having conventional HCC (cHCC) with or without underlying liver disease, fibrolamellar carcinoma (FLC), and hepatoblastoma with HCC features (HB-HCC). Univariate and multivariate analyses identified predictors of mortality and relapse. RESULTS: In total, 262 children were identified; and an institutional histologic review revealed 110 cHCCs (42%; 69 normal background liver, 34 inflammatory/cirrhotic, 7 unknown), 119 FLCs (45%), and 33 HB-HCCs (12%). The authors observed notable differences in presentation and behavior among tumor subtypes, including increased lymph node involvement in FLC and higher stage in cHCC. Factors associated with mortality included cHCC (hazard ratio [HR], 1.63; P = .038), elevated α-fetoprotein (HR, 3.1; P = .014), multifocality (HR, 2.4; P < .001), and PRETEXT (pretreatment extent of disease) stage IV (HR, 5.76; P < .001). Multivariate analysis identified increased mortality in cHCC versus FLC (HR, 2.2; P = .004) and in unresectable tumors (HR, 3.4; P < .001). Disease-free status at any point predicted survival. CONCLUSIONS: This multi-institutional, detailed data set allowed a comprehensive analysis of outcomes for children with these rare hepatocellular neoplasms. The current data demonstrated that pediatric HCC subtypes are not equivalent entities because FLC and cHCC have distinct anatomic patterns and outcomes in concert with their known molecular differences. This data set will be further used to elucidate the impact of histology on specific treatment responses, with the goal of designing risk-stratified algorithms for children with HCC. LAY SUMMARY: This is the largest reported granular data set on children with hepatocellular carcinoma. The study evaluates different subtypes of hepatocellular carcinoma and identifies key differences between subtypes. This information is pivotal in improving understanding of these rare cancers and may be used to improve clinical management and subsequent outcome in children with these rare malignancies.

Pediatric palliative care and surgery.

Care for pediatric patients with serious or potentially life-limiting illness involves the interplay of multiple medical and surgical teams within the hospital. Pediatric surgeons are capable of performing procedures that can improve the quality of life for children facing serious illness, but which also carry the potential for significant risk and burden. Patients and families are often faced with decisions about invasive surgical procedures and interventions, stressing the need for seamless collaboration between palliative care and surgical providers. Equally important is the need for clear and open-ended communication with patients and families by all medical teams to determine if potential surgical procedures and interventions align with their goals and to ensure that the perceived benefits of interventions outweigh any risks. Over the last two decades, pediatric palliative care has grown into a thriving medical subspecialty Despite the importance of collaborative care, there is lack of literature on the interaction of pediatric surgery and palliative care and the role of pediatric surgeons in providing primary palliative care. This review defines surgical pediatric palliative care, and provides an in-depth discussion of the unique complexities involved in caring for children with serious and potentially life-limiting illness, while highlighting specific challenges through detailed case presentations.

Management of broncho-esophageal fistula after button battery ingestion.

Button battery ingestion can cause serious injury or death in young children who cannot communicate symptoms. An 18-month-old male presented after his mother noted drooling, nonbilious emesis and a metallic smell to his breath. He underwent rigid esophagoscopy and a 3-V 20-mm button battery was removed. Subsequent bronchoscopy after a 1-week interval revealed progression to a large broncho-esophageal fistula on the posterior wall of the right mainstem bronchus past the carina. A fenestrated nasogastric tube for local control of secretion and a feeding jejunostomy was placed. Six weeks later, the patient underwent a right thoracotomy for division and repair of the fistula and intercostal muscle flap interposition. Utilizing a well-placed fenestrated nasogastric tube to manage secretions can help reduce fistula size and improve conservative management results. When surgical repair is required, an intercostal muscle flap can reinforce fistula closure while simultaneously buttressing the bronchus and esophagus.

Improving trauma tertiary survey performance and missed injury identification using an education-based quality improvement initiative.

BACKGROUND: Performance of a trauma tertiary survey (TTS) reduces rates of missed injuries, but performance has been inconsistent at trauma centers. The objectives of this study were to assess whether quality improvement (QI) efforts would increase the frequency of TTS documentation and determine if TTS documentation would increase identification of traumatic injuries. Our hypothesis was that QI efforts would improve documentation of the TTS. METHODS: Before-and-after analysis of QI interventions at a level 1 trauma center was performed. The interventions included an electronic template for TTS documentation, customized educational sessions, and emphasis from trauma leadership on TTS performance. The primary outcome was documentation of the TTS. Detection of additional injuries based on tertiary evaluation was a secondary outcome. Associations between outcomes and categorical patient and encounter characteristics were assessed using χ2 tests. RESULTS: Overall, 592 trauma encounters were reviewed (296 preimplementation and 296 postimplementation). Trauma tertiary survey documentation was significantly higher after implementation of the interventions (30.1% preimplementation vs. 85.1% postimplementation, p < 0.001). Preimplementation documentation of the TTS was less likely earlier in the academic year (14.3% first academic quarter vs. 46.5% last academic quarter, p < 0.001), but this temporal pattern was no longer evident postimplementation (88.5% first academic quarter vs. 77.9% last academic quarter, p = 0.126). Patients were more likely to have a missed traumatic injury diagnosed on TTS postimplementation (1.7% in preimplementation vs. 5.7% postimplementation, p = 0.009). CONCLUSION: Documentation of the TTS and missed injury detection rates were significantly increased following implementation of a bundle of QI interventions. The association between time of year and documentation of the TTS was also attenuated, likely through reduction of the resident learning curve. Targeted efforts to improve TTS performance may improve outcomes for trauma patients at teaching hospitals. LEVEL OF EVIDENCE: Care management, Level IV.

Computed Tomography of Adult Rhinosinusitis.

Rhinosinusitis involves symptomatic inflammation of the paranasal sinuses. This common condition affects approximately 1 in 7 adults in the United States and is associated with significant morbidity and financial costs. Although rhinosinusitis primarily is a clinical diagnosis, medical imaging plays a unique role in sinusitis diagnosis and treatment, particularly in presurgical planning. This article reviews sinus anatomy, the characteristics of rhinosinusitis, and the modalities used to image the paranasal sinuses.

Neosuture formation after endoscope-assisted craniosynostosis repair.

OBJECTIVE The goal of this study was to identify the rate of neosuture formation in patients with craniosynostosis treated with endoscope-assisted strip craniectomy and investigate whether neosuture formation in sagittal craniosynostosis has an effect on postoperative calvarial shape. METHODS The authors retrospectively reviewed 166 cases of nonsyndromic craniosynostosis that underwent endoscope-assisted repair between 2006 and 2014. Preoperative and 1-year postoperative head CT scans were evaluated, and the rate of neosuture formation was calculated. Three-dimensional reconstructions of the CT data were used to measure cephalic index (CI) (ratio of head width and length) of patients with sagittal synostosis. Regression analysis was used to calculate significant differences between patients with and without neosuture accounting for age at surgery and preoperative CI. RESULTS Review of 96 patients revealed that some degree of neosuture development occurred in 23 patients (23.9%): 16 sagittal, 2 bilateral coronal, 4 unilateral coronal, and 1 lambdoid synostosis. Complete neosuture formation was seen in 14 of those 23 patients (9 of 16 sagittal, 1 of 2 bilateral coronal, 3 of 4 unilateral coronal, and 1 of 1 lambdoid). Mean pre- and postoperative CI in the complete sagittal neosuture group was 67.4% and 75.5%, respectively, and in the non-neosuture group was 69.8% and 74.4%, respectively. There was no statistically significant difference in the CI between the neosuture and fused suture groups preoperatively or 17 months postoperatively in patients with sagittal synostosis. CONCLUSIONS Neosuture development can occur after endoscope-assisted strip craniectomy and molding helmet therapy for patients with craniosynostosis. Although the authors did not detect a significant difference in calvarial shape postoperatively in the group with sagittal synostosis, the relevance of neosuture formation remains to be determined. Further studies are required to discover long-term outcomes comparing patients with and without neosuture formation.

Antibody mediated therapy targeting CD47 inhibits tumor progression of hepatocellular carcinoma.

Human hepatocellular carcinoma (HCC) has a high rate of tumor recurrence and metastasis, resulting in shortened survival times. The efficacy of current systemic therapies for HCC is limited. In this study, we used xenograft tumor models to investigate the use of antibodies that block CD47 and inhibit HCC tumor growth. Immunostaining of tumor tissue and HCC cell lines demonstrated CD47 over-expression in HCC as compared to normal hepatocytes. Macrophage phagocytosis of HCC cells was increased after treatment with CD47 antibodies (CD47mAbs) that block CD47 binding to SIRPα. Further, CD47 blockade inhibited tumor growth in both heterotopic and orthotopic models of HCC, and promoted the migration of macrophages into the tumor mass. Our results demonstrate that targeting CD47 by specific antibodies has potential immunotherapeutic efficacy in human HCC.

Disability and the practice of public history: an introduction.

Museums, exhibitions, and public history have long engaged with the subject matter of disability. Shared social conventions and exhibition traditions about people with disabilities--the common stereotypes of people as persevering heroes or objects of pity--have often led to skewed and inaccurate historical presentations. The medical model of disability, equally strong in framing disability, has also reduced the range of possibilities for including content for the public. More recently, greater understanding of diversity and of the importance of interpreting the history of all people has begun to push inclusion beyond simple issues into content.

Osteoarthritis and MR imaging.

Although osteoarthritis (OA) is a common disease affecting millions of Americans, OA treatment is difficult to monitor because of the lack of consistent, objective disease standards. This article reviews the diagnosis and treatment of OA, with particular emphasis on the role of magnetic resonance (MR) in imaging the disease. After completing this article, readers will be able to: List the known risk factors for OA. Discuss normal and abnormal joint anatomy and physiology. Recognize OA symptoms. Describe diagnostic criteria for OA. Discuss the appearance of articular joint structures on MR. Explain the nonpharmacological and pharmacological treatment of OA. Discuss the role of MR in OA research.