High density dislocations enhance creep ageing response and mechanical properties in 2195 alloy sheet

The creep strain of conventionally treated 2195 alloy is very low,increasing the difficulty of manufacturing Al-Cu-Li alloy sheet parts by creep age forming.Therefore,finding a solution to improve the creep formability of Al-Cu-Li alloy is vital.A thorough comparison of the effects of cryo-deformation and ambient temperature large pre-deformation(LPD)on the creep ageing response in the 2195 alloy sheet at 160℃with different stresses has been made.The evolution of dislocations and precipitates during creep ageing of LPD alloys are revealed by X-ray diffraction and transmission electron microscopy.High-quality 2195 alloy sheet largely pre-deformed by 80%without edge-cracking is obtained by cryo-rolling at liquid nitrogen temperature,while severe edge-cracking occurs during room temperature rolling.The creep formability and strength of the 2195 alloy are both enhanced by introducing pre-existing dislocations with a density over 1.4×10^(15)m^(−2).At 160℃and 150 MPa,creep strain and creep-aged strength generally increases by 4−6 times and 30−50 MPa in the LPD sample,respectively,compared to conventional T3 alloy counterpart.The elongation of creep-aged LPD sample is low but remains relevant for application.The high-density dislocations,though existing in the form of dislocation tangles,promote the formation of refined T1 precipitates with a uniform dispersion.

Moiré superlattices arising from growth induced by screw dislocations in layered materials

Moiré superlattices(MSLs) are modulated structures produced from homogeneous or heterogeneous two-dimensional layers stacked with a twist angle and/or lattice mismatch. Enriching the methods for fabricating MSL and realizing the unique emergent properties are key challenges in its investigation. Here we recommend that the spiral dislocation driven growth is another optional method for the preparation of high quality MSL samples. The spiral structure stabilizes the constant out-of-plane lattice distance, causing the variations in electronic and optical properties. Taking SnS_(2) MSL as an example, we find prominent properties including large band gap reduction(~ 0.4 e V) and enhanced optical activity. Firstprinciples calculations reveal that these unusual properties can be ascribed to the locally enhanced interlayer interaction associated with the Moiré potential modulation. We believe that the spiral dislocation driven growth would be a powerful method to expand the MSL family and broaden their scope of application.

TINAVI robot-assisted one-stage anteroposterior surgery in lateral position for severe thoracolumbar fracture dislocation:A case report

BACKGROUND The combined anterior/posterior approach appears to be capable of reconstructing spinal stability,correcting thoracolumbar deformity,and promoting neural recovery in severe thoracolumbar fracture dislocation.However,this type of operation requires changing the body position during the procedure,resulting in a lengthy operation time.As a universal surgical robot,TINAVI robot has achieved good surgical results in clinical surgery.But to our knowledge,no reports describing TINAVI robot-assisted single lateral position anteroposterior surgery for thoracolumbar fracture dislocation.CASE SUMMARY We describe a case of a 16-year-old female patient with severe thoracolumbar fracture and dislocation underwent surgery assisted by the TINAVI robot.A onestage combined anterior and posterior operation was performed on a severe thoracolumbar fracture dislocation using the TINAVI robot,and the operation was completed in right lateral position.CONCLUSION The TINAVI robot-assisted one-stage anterior and posterior surgery in right lateral position for severe thoracolumbar fracture and dislocation is both safe and effective.

New direction for surgery:Super minimally invasive surgery

The top goal of modern medicine is treating disease without destroying organ structures and making patients as healthy as they were before their sickness.Minimally invasive surgery(MIS)has dominated the surgical realm because of its lesser invasiveness.However,changes in anatomical structures of the body and reconstruction of internal organs or different organs are common after traditional surgery or MIS,decreasing the quality of life of patients post-operation.Thus,I propose a new treatment mode,super MIS(SMIS),which is defined as“curing a disease or lesion which used to be treated by MIS while preserving the integrity of the organs”.In this study,I describe the origin,definition,operative channels,advantages,and future perspectives of SMIS.

Bariatric surgery and diabetes:Current challenges and perspectives

Diabetes mellitus(DM)and obesity have become public issues of global concern.Bariatric surgery for the treatment of obesity combined with type 2 DM has been shown to be a safe and effective approach;however,there are limited studies that have systematically addressed the challenges of surgical treatment of obesity combined with DM.In this review,we summarize and answer the most pressing questions in the field of surgical treatment of obesity-associated DM.I believe that our insights will be of great help to clinicians in their daily practice.

Artificial Intelligence and Computer Vision during Surgery: Discussing Laparoscopic Images with ChatGPT4—Preliminary Results

Introduction: Ultrafast latest developments in artificial intelligence (ΑΙ) have recently multiplied concerns regarding the future of robotic autonomy in surgery. However, the literature on the topic is still scarce. Aim: To test a novel AI commercially available tool for image analysis on a series of laparoscopic scenes. Methods: The research tools included OPENAI CHATGPT 4.0 with its corresponding image recognition plugin which was fed with a list of 100 laparoscopic selected snapshots from common surgical procedures. In order to score reliability of received responses from image-recognition bot, two corresponding scales were developed ranging from 0 - 5. The set of images was divided into two groups: unlabeled (Group A) and labeled (Group B), and according to the type of surgical procedure or image resolution. Results: AI was able to recognize correctly the context of surgical-related images in 97% of its reports. For the labeled surgical pictures, the image-processing bot scored 3.95/5 (79%), whilst for the unlabeled, it scored 2.905/5 (58.1%). Phases of the procedure were commented in detail, after all successful interpretations. With rates 4 - 5/5, the chatbot was able to talk in detail about the indications, contraindications, stages, instrumentation, complications and outcome rates of the operation discussed. Conclusion: Interaction between surgeon and chatbot appears to be an interesting frontend for further research by clinicians in parallel with evolution of its complex underlying infrastructure. In this early phase of using artificial intelligence for image recognition in surgery, no safe conclusions can be drawn by small cohorts with commercially available software. Further development of medically-oriented AI software and clinical world awareness are expected to bring fruitful information on the topic in the years to come.

Fully automatic AI segmentation of oral surgery-related tissues based on cone beam computed tomography images

Accurate segmentation of oral surgery-related tissues from cone beam computed tomography(CBCT)images can significantly accelerate treatment planning and improve surgical accuracy.In this paper,we propose a fully automated tissue segmentation system for dental implant surgery.Specifically,we propose an image preprocessing method based on data distribution histograms,which can adaptively process CBCT images with different parameters.Based on this,we use the bone segmentation network to obtain the segmentation results of alveolar bone,teeth,and maxillary sinus.We use the tooth and mandibular regions as the ROI regions of tooth segmentation and mandibular nerve tube segmentation to achieve the corresponding tasks.The tooth segmentation results can obtain the order information of the dentition.The corresponding experimental results show that our method can achieve higher segmentation accuracy and efficiency compared to existing methods.Its average Dice scores on the tooth,alveolar bone,maxillary sinus,and mandibular canal segmentation tasks were 96.5%,95.4%,93.6%,and 94.8%,respectively.These results demonstrate that it can accelerate the development of digital dentistry.

Dissociation of edge and screw pyramidal Ⅰ and Ⅱ dislocations in magnesium

Pyramidal dislocations in magnesium (Mg) and other hexagonal close-packed metals play an important role in accommodating plastic strains along the c-axis.Bulk single crystal Mg only presents very limited plasticity in c-axis compression,and this behavior was attributed to out-of-plane dissociation of pyramidal dislocations onto the basal plane and resulted in an immobile dislocation configuration.In contrast,other simulations and experiments reported in-plane dissociation of pyramidal dislocations on their slip planes.Thus,the core structure and mode of dissociation of pyramidal dislocations are still not well understood.To better understand the dissociation behavior of pyramidal dislocations in Mg at room temperature,in this work,atomistic simulations were conducted to investigate four types of pyramidal dislocations at 300 K:edge and screw Py-Ⅰ on{1011},edge and screw Py-Ⅱ on{1122}by using a modified embedded atom method (MEAM) potential for Mg and anisotropic elasticity dislocation model.The results show that when energy minimization was performed before relaxation,in-plane dissociation of edge dislocations on respective pyramidal plane could be obtained at room temperature for all four types of dislocation.Without energy minimization,the edge dislocations dissociated out-of-plane onto the basal plane.Calculations of potential energy and hydrostatic stress of individual atoms at the edge dislocation core show that the extraordinarily high energy and atomic stresses in the as-constructed dislocation structures caused the out-of-plane dissociation onto the basal plane.The core structures of all four types of pyramidal dislocation after in-plane dissociation were analyzed by computing the distribution of the Burgers vector.

Is recovery enhancement after gastric cancer surgery really a safe approach for elderly patients?

BACKGROUND This study aimed to evaluate the safety of enhanced recovery after surgery(ERAS)in elderly patients with gastric cancer(GC).AIM To evaluate the safety of ERAS in elderly patients with GC.METHODS The PubMed,EMBASE,and Cochrane Library databases were used to search for eligible studies from inception to April 1,2023.The mean difference(MD),odds ratio(OR)and 95%confidence interval(95%CI)were pooled for analysis.The quality of the included studies was evaluated using the Newcastle-Ottawa Scale scores.We used Stata(V.16.0)software for data analysis.RESULTS This study consists of six studies involving 878 elderly patients.By analyzing the clinical outcomes,we found that the ERAS group had shorter postoperative hospital stays(MD=-0.51,I2=0.00%,95%CI=-0.72 to-0.30,P=0.00);earlier times to first flatus(defecation;MD=-0.30,I²=0.00%,95%CI=-0.55 to-0.06,P=0.02);less intestinal obstruction(OR=3.24,I2=0.00%,95%CI=1.07 to 9.78,P=0.04);less nausea and vomiting(OR=4.07,I2=0.00%,95%CI=1.29 to 12.84,P=0.02);and less gastric retention(OR=5.69,I2=2.46%,95%CI=2.00 to 16.20,P=0.00).Our results showed that the conventional group had a greater mortality rate than the ERAS group(OR=0.24,I2=0.00%,95%CI=0.07 to 0.84,P=0.03).However,there was no statistically significant difference in major complications between the ERAS group and the conventional group(OR=0.67,I2=0.00%,95%CI=0.38 to 1.18,P=0.16).CONCLUSION Compared to those with conventional recovery,elderly GC patients who received the ERAS protocol after surgery had a lower risk of mortality.

Recent Traumatic Dislocations of the Shoulder in Adults: Epidemiological, Therapeutic and Evolutionary Aspects

Introduction: Shoulder dislocations represent about 50% of all joint dislocations. The objective was to describe the epidemiological, therapeutic and evolutionary aspects of traumatic shoulder dislocations in Bouaké. Methods: This retrospective and descriptive study was conducted between January 2017 and December 2019. It concerned patients over 15 years of age with a recent traumatic shoulder dislocation treated and followed in the department. The variables studied were epidemiological, therapeutic and evolutionary. The severity of the trauma was assessed according to the Injury Severity Score (ISS). Functional outcome was assessed according to the Constant score. Results: There were 49 patients (49 dislocations) out of 22,569 patients. The prevalence was 0.2%. The mean age was 32 years (17 - 62). There were 38 men (77.5%). The sex ratio was 3.4. Students predominated (n = 10;20.4%). The etiology was dominated by road traffic accidents (n = 19;38.8%). Anterior dislocation was the most common (n = 45;92%). The ISS score was minor (n = 46;93.8%). The mean time to reduction was 7 hours (4 - 16). Orthopaedic reduction using the Kocher technique predominated (n = 44;89.8%). The mean duration of external rotation immobilisation of the shoulder was 23 days (16 - 45). Recurrence occurred in 8 patients (21.6%). The functional outcome at a mean Constant follow-up of 15 months (8 - 20) was satisfactory (n = 44;89.8%). Conclusion: Traumatic dislocation of the shoulder represented 0.2%. Treatment was mainly orthopaedic. Recurrence was rare.

Enhanced recovery after surgery in elderly patients with non-small cell lung cancer who underwent video-assisted thoracic surgery

BACKGROUND This study was designed to investigate the clinical outcomes of enhanced recovery after surgery(ERAS)in the perioperative period in elderly patients with nonsmall cell lung cancer(NSCLC).AIM To investigate the potential enhancement of video-assisted thoracic surgery(VATS)in postoperative recovery in elderly patients with NSCLC.METHODS We retrospectively analysed the clinical data of 85 elderly NSCLC patients who underwent ERAS(the ERAS group)and 327 elderly NSCLC patients who received routine care(the control group)after VATS at the Department of Thoracic Surgery of Peking University Shenzhen Hospital between May 2015 and April 2017.After propensity score matching of baseline data,we analysed the postoperative stay,total hospital expenses,postoperative 48-h pain score,and postoperative complication rate for the 2 groups of patients who underwent lobectomy or sublobar resection.RESULTS After propensity score matching,ERAS significantly reduced the postoperative hospital stay(6.96±4.16 vs 8.48±4.18 d,P=0.001)and total hospital expenses(48875.27±18437.5 vs 55497.64±21168.63 CNY,P=0.014)and improved the satisfaction score(79.8±7.55 vs 77.35±7.72,P=0.029)relative to those for routine care.No significant between-group difference was observed in postoperative 48-h pain score(4.68±1.69 vs 5.28±2.1,P=0.090)or postoperative complication rate(21.2%vs 27.1%,P=0.371).Subgroup analysis showed that ERAS significantly reduced the postoperative hospital stay and total hospital expenses and increased the satisfaction score of patients who underwent lobectomy but not of patients who underwent sublobar resection.CONCLUSION ERAS effectively reduced the postoperative hospital stay and total hospital expenses and improved the satisfaction score in the perioperative period for elderly NSCLC patients who underwent lobectomy but not for patients who underwent sublobar resection.

Epidemiology of shoulder dislocations presenting to United States emergency departments:An updated ten-year study

BACKGROUND Glenohumeral dislocation is a common injury that may predispose patients to chronic pain and instability.However,there is a paucity of current data available regarding the epidemiological trends of this injury.AIM To provide an updated,comparative assessment of the epidemiology of shoulder dislocations presenting to emergency departments in the United States.We also sought to analyze patient demographic risk factors and consumer products associated with dislocation events.METHODS Data were obtained from the national electronic injury surveillance system database for glenohumeral dislocations between 2012 and 2021.Incidence,age,sex,and injury characteristics were analyzed using weighted population statistics as well as incidence rates and 95%confidence intervals(CI).RESULTS In total,an estimated 773039 shoulder dislocations(CI:640598-905481)presented to emergency rooms across the United States during the study period.The annual incidence rate was 23.96 per 100000 persons and the average patient age at the time of injury was 37.1 years.Significantly more male patients sustained dislocations than female patients(537189,69.5%,vs 235834,30.5%,P<0.001).With regard to associated consumer products,sports and recreation equipment were involved in the highest proportion of incidents(44.31%),followed by home structures and construction materials(21.22%),and home furnishings,fixtures,and accessories(21.21%).Regarding product sub-groups,stairs,ramps,landings,floors was cited in the greatest number of cases(131745).CONCLUSION The national annual incidence rate of glenohumeral dislocations throughout the study period was approximately 23.92 per 100000 persons.Male adolescents sustained the highest proportion of dislocations,with a peak incidence in age group 15-20 years,predominantly secondary to participation in sporting and recreational activities.Conversely,women experienced a relatively consistent incidence of dislocation throughout their lifespan.After age 63,the incidence rate of dislocations in females was found to surpass that observed in males.

Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope images.In this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma surgery.Sixteen ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and instruments.After surgery,a subjective feedback survey about the user experience was taken.The experiment results showed that our system can help surgeons easily locate important tissue structures during surgery.The custom-made instruments also solved the shadowing problem in OCT imaging.Surgeons preferred to use the system in their future practice.

Uterine artery pseudoaneurysm caused by hysteroscopic surgery: A case report

BACKGROUND We report a case of uterine artery pseudoaneurysm(UAP)occurrence during hysteroscopic endometrial polypectomy and its treatment via uterine artery embolization(UAE).CASE SUMMARY A 48-year-old primigravid,primiparous patient was incidentally found to have an endometrial polyp during a health checkup,and underwent a hysteroscopic polypectomy at another hospital.Her cervix was dilated with a Laminken-R®device.After the Laminken-R®was withdrawn,a large amount of genital bleeding was observed.This bleeding persisted after the hysteroscopic polypectomy,and,as hemostasis became impossible,the patient was transferred to our hospital by ambulance.On arrival,transvaginal ultrasonography revealed a 3-cm hypoechoic mass with a swirling internal pulse on the right side of the uterus,and color Doppler ultrasonography showed feeder vessels penetrating the mass.Pelvic contrast-enhanced computed tomography(CT)confirmed the presence of a mass at this site,and vascular proliferation was observed within the uterine cavity.Consequently,UAP was diagnosed,and UAE was performed.The patient’s postoperative course was uneventful,and 6 mo post-UAE,no recurrence of blood flow to the UAP was observed.CONCLUSION When abnormal genital bleeding occurs during hysteroscopic surgery,ultrasonography and contrast-enhanced CT can assist in the detection of early UAPs.

Effect of bariatric surgery on metabolism in diabetes and obesity comorbidity:Insight from recent research

Obesity is a prevalent cause of diabetes mellitus(DM)and is a serious danger to human health.Type 2 DM(T2DM)mostly occurs along with obesity.Foodborne obesity-induced DM is caused by an excessive long-term diet and surplus energy.Bariatric surgery can improve the symptoms of T2DM in some obese patients.But different types of bariatric surgery may have different effects.There are some models built by researchers to discuss the surgical procedures’effects on me-tabolism in diabetes animal models and diabetes patients.It is high time to conclude all this effects and recommend procedures that can better improve metabolism.

Treatment of hemolymphangioma by robotic surgery: A case report

BACKGROUND Hemolymphangioma of the jejunum is rare and lacks clinical specificity,and can manifest as gastrointestinal bleeding,abdominal pain,and intestinal obstruction.Computed tomography,magnetic resonance imaging,and other examinations show certain characteristics of the disease,but lack accuracy.Although capsule endoscopy and enteroscopy make up for this deficiency,the diagnosis also still re-quires pathology.CASE SUMMARY A male patient was admitted to the hospital due to abdominal distension and abdominal pain,but a specific diagnosis by computed tomography examination was not obtained.Partial resection of the small intestine was performed by robotic surgery,and postoperative pathological biopsy confirmed the diagnosis of hemo-lymphangioma.No recurrence in the follow-up examination was observed.CONCLUSION Robotic surgery is an effective way to treat hemolymphangioma through minima-lly invasive techniques under the concept of rapid rehabilitation.

Efficacy and safety of minimally invasive laparoscopic surgery under general anesthesia for ovarian cancer

BACKGROUND Ovarian cancer is one of the most common malignant tumors in female reproductive system in the world,and the choice of its treatment is very important for the survival rate and prognosis of patients.Traditional open surgery is the main treatment for ovarian cancer,but it has the disadvantages of big trauma and slow recovery.With the continuous development of minimally invasive technology,minimally invasive laparoscopic surgery under general anesthesia has been gradually applied to the treatment of ovarian cancer because of its advantages of less trauma and quick recovery.However,the efficacy and safety of minimally invasive laparoscopic surgery under general anesthesia in the treatment of ovarian cancer are still controversial.AIM To explore the efficacy and safety of general anesthesia minimally invasive surgery in the treatment of ovarian cancer.METHODS The clinical data of 90 patients with early ovarian cancer in our hospital were analyzed retrospectively.According to the different surgical treatment methods,patients were divided into study group and control group(45 cases in each group).The study group received minimally invasive laparoscopic surgery under general anesthesia for ovarian cancer,while the control group received traditional open surgery for ovarian cancer.The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire(EORTC QLQ-C30),clinical efficacy and safety of the two groups were compared.RESULTS The intraoperative blood loss,length of hospital stay,postoperative gas evacuation time,and postoperative EORTC QLQ-C30 score of the study group were significantly better than those of the control group(P<0.05).The incidence of postoperative complications in the study group was significantly lower than in the control group(P<0.05).The two groups had no significant differences in the preoperative adrenocorticotropic hormone(ACTH),androstenedione(AD),cortisol(Cor),cluster of differentiation 3 positive(CD3+),and cluster of differentiation 4 positive(CD4+)indexes(P>0.05).In contrast,postoperatively,the study group's ACTH,AD,and Cor indexes were lower,and the CD3+and CD4+indexes were higher than those in the control group(P<0.05).CONCLUSION Minimally invasive laparoscopic surgery under general anesthesia in patients with early ovarian cancer can significantly improve the efficacy and safety,improve the short-term prognosis and quality of life of patients,and is worth popularizing.

Subtalar dislocations:Mechanisms,clinical presentation and methods of reduction

Subtalar joint is a complex joint in hindfoot formed by the talus superiorly and the calcaneus and navicular inferiorly.Subtalar dislocations are high-mechanism injuries,which are caused by simultaneous dislocation of both talonavicular and talocalcaneal joints,without major fracture of the talus.They are usually classified as medial(most common),lateral,anterior and posterior dislocations,based on the position of foot in relation to talus and the indirect forces that have been applied to cause this significant injury.They are usually diagnosed by X rays,but computed tomography and magnetic resonance imaging can be used to identify associated intra-articular fractures and peri-talar soft tissue injuries respectively.Majority being closed injuries,can be managed in ED by closed reduction and cast immobilisation,but if they are open,have poor outcomes.Complications that ensue open dislocations are post-traumatic arthritis,instability and avascular necrosis.

Effect of ankle versus thigh tourniquets on post-operative pain in foot and ankle surgery

BACKGROUND Tourniquets are commonly used in elective extremity orthopaedic surgery to reduce blood loss,improve visualization in the surgical field,and to potentially reduce surgical time.There is a lack of consensus in existing guidelines regarding the optimal tourniquet pressure,placement site,and duration of use.There is a paucity of data on the relationship between the site of a tourniquet and postoperative pain in foot and ankle surgery.AIM To explore the relationship between tourniquet site and intensity of post-operative pain scores in patients undergoing elective foot and ankle surgery.METHODS Retrospective analysis of prospectively collected data on 201 patients who underwent foot and ankle surgery in a single institution was undertaken.Intraoperative tourniquet duration,tourniquet pressure and site,and postoperative pain scores using Visual Analogue Score were collected in immediate recovery,at six hours and at 24 h post-op.Scatter plots were used to analyse the data and to assess for the statistical correlation between tourniquet pressure,duration,site,and pain scores using Pearson correlation coefficient.RESULTS All patients who underwent foot and ankle surgery had tourniquet pressure of 250 mmHg for ankle tourniquet and 300 mmHg for thigh.There was no correlation between the site of the tourniquet and pain scores in recovery,at six hours and after 24 h.There was a weak correlation between tourniquet time and Visual Analogue Score immediately post-op(r=0.14,P=0.04)but not at six or 24 h post-operatively.CONCLUSION This study shows that there was no statistically significant correlation between tourniquet pressure,site and postop pain in patients undergoing foot and ankle surgery.The choice of using a tourniquet is based on the surgeon's preference,with the goal of minimizing the duration of its application at the operative site.

Incidence of sports-related sternoclavicular joint dislocations in the United States over the last two decades

BACKGROUND Epidemiological understanding of acute sternoclavicular(SC)dislocations secondary to sports across the United States is poorly defined.AIM To identify and assess epidemiological trends of SC dislocations occurring secondary to sports-related mechanisms across United States over the past two decades.METHODS This cross-sectional,descriptive epidemiological study evaluates epidemiological trends of SC dislocations from sports that present to emergency departments(EDs)across the United States.Data were obtained from the National Electronic Injury Surveillance System database spanning two decades.Data on incidence,patient demographics,mechanisms of injury,dislocation types,incident locales,and patient dispositions were collected.RESULTS 1622 SC dislocations occurred nationwide from 2001 to 2020[incidence=0.262/1000000 people,confidence interval(CI)=0.250-0.275],comprising 0.1%of shoulder/upper trunk dislocations.Most patients were male(91%,n=1480)and aged 5-17(61%,n=982).Football,wrestling,and biking were the most frequently implicated sports,with contact sports responsible for 59%of athletic injuries(n=961).Recreational vehicle-related sports injuries,such as all-terrain vehicles,dirt bikes,and mopeds accounted for 7.8%of all injuries(n=126),with dirt bikes specifically comprising 3.7%(n=61).Ultimately,82%were discharged from the ED(n=1337),12%were admitted(n=194),and 6%were transferred(n=90).All recorded posterior dislocations were admitted or transferred from the ED.Patients sustaining SC dislocations from contact sports had a significantly increased risk of hospital admission or transfer rather than discharge from the ED as compared to patients whose injuries were from non-contact sports(incidence rate ratio=1.46,CI:=1.32-1.61,P<0.001).CONCLUSION SC dislocations from sports continue to be rare with a stably low incidence over the past two decades,likely comprising a smaller proportion of shoulder dislocations than previously thought.Contact sports are a frequent source of injury,especially among school-aged and teenage males.Most patients are discharged directly from the ED;however,a substantial number are hospitalized,many of which had documented posterior dislocations.Ultimately,understanding the epidemiology and mechanism-related trends of acute SC dislocations is important given the potential severity of these injuries,concentration in a specific population,and uncertainty linked to rare presentation.