Point of Care Ultrasound in Pediatric Surgery across the European Region-European Pediatric Surgery Association Endorsed Survey.

INTRODUCTION: Our purpose was to assess the state of training, clinical practice, and barriers to use point-of-care ultrasound (POCUS) in pediatric surgery in Europe. METHODS: An electronic survey was disseminated among European pediatric surgeons utilizing the European Pediatric Surgery Association network and other existing networks. RESULTS: There were 186 respondents from 27 European countries and 7 non-European countries. In most countries (86.6%; N = 161), the initial ultrasound for acute admissions is performed by radiologists, with 1 to 6 hours turnover in 62.9% (N = 117) of urgent cases. Ultrasound by pediatric surgeons (point-of-care ultrasound/POCUS) is performed by 48.4% (N = 90) of respondents, with 29% (N = 54) using it at least once per week. The most common indications for POCUS include abdominal focused abdominal sonography in trauma (53.8%; N = 100), diagnosis of appendicitis (41.9%; N = 78), and intussusception (44.6%; N = 84). In malrotation-volvulus, 28.5% (N = 53) used ultrasound for its diagnosis, while 27.5% (N = 51) would not see an indication here. Training in POCUS occurred informally for 55.4% (N = 103) of participants, while 31.2% (N = 58) attended formal training courses. Almost all respondents wanted to attain further POCUS training (89.3%; N = 166), only 7% (N = 13) did not think this would be useful. For 73.1% (N = 136), POCUS is not currently part of the pediatric surgery training curriculum in their country. Perceived barriers to POCUS use include a lack of training opportunities (26.3% [N = 49]) and a paucity of portable ultrasound machines (17.8% [N = 33]). CONCLUSION: There is a wide spectrum of POCUS use in pediatric surgery across Europe. For those surgeons who practice POCUS, it is most used for the diagnosis of abdominal conditions. There are differing views among clinicians concerning the most useful applications of POCUS. The extent to which ultrasound is taught during pediatric surgery training differs substantially across European curricula.

The Outcome of Laparoscopic Versus Open Appendectomy in Childhood.

BACKGROUND: Appendectomy in children is performed either lapa - roscopically (LA) or by open surgery (OA). We studied whether, and how, the outcome is affected by the technique used and by the intraoperative conversion of LA to OA. METHODS: We analyzed routine data from children and adolescents in three age groups (1-5 years, 6-12 years, and 13-17 years) who were insured by the AOK statutory health insurance carrier in Germany and who underwent appendectomy in the period 2017-2019. General surgical complications and reoperations within 90 days were assessed with relevant indicators. Associations between the surgical technique and these indicators were studied with logistic regression. RESULTS: Of the 21 541 patients included in the study, general surgical complications were observed in 2.1% and reoperations in 1.8% overall. Broken down by age group, the corresponding figures were 5.4% and 4.4% (age 1 to 5), 2.5% and 1.8% (age 6 to 12), and 1.5% and 1.6% (age 13 to 17). The main risk factors for complications and reoperations were acute complicated appendicitis and conversion from LA to OA. Regression analysis revealed similar outcomes with OA compared to LA in the 1-to-5 age group, (odds ratios and 95% confidence intervals: 1.1 [0.6; 2.1] for general surgical complications and 1.5 [0.8; 2.7] for reoperations), but worse outcomes with OA in the other two age groups (age 6 to 12: 1.9 [1.2; 2.9] and 2.1 [1.5; 2.9]; age 13 to 17: 1.7 [1.0; 2.9] and 2.2 [1.4; 3.6]). When conversions were assigned to the LA group, the odds ratio (OA compared to LA) for reoperation across all age groups was 3.5 [2.8; 4.4] in patients with acute uncomplicated appendicitis and 4.2 [3.4; 5.3] in patients with complicated appendicitis. Complicated appendicitis also increased the rate of general surgical complications and the length of stay in hospital. CONCLUSION: Among children in the two older age groups, LA was followed by fewer general surgical complications and reoperations than OA. These differences were less pronounced when conversions were counted as belonging to the LA group. Children aged 1-5 appear to benefit the least from the lapa - roscopic technique.

Ankle Joint MRI-Comparison of Image Quality and Effect of Sports-Related Stress.

OBJECTIVES: The main aims of the study were the evaluation of stress-related effects (strenuous vs. non-strenuous sport vs. nonathletes) in stimulating or reducing influences on cartilage volume in the ankle joint and the evaluation of the image quality of a magnetic resonance imaging (MRI) device with a field strength of 3.0 Tesla compared to one of 1.5 Tesla. METHODS: A total of 15 subjects (6 male, 9 female) aged 19-33 years participated voluntarily in this prospective study. The subjects were divided into three groups: high-performance athletes of the German Football Association (DFB) (football/soccer = strenuous sport), high-performance athletes of the German Swimming Association (DSV) (swimming = non-strenuous sport), and nonathletes. MRI was performed on both ankle joints of all subjects in the 1.5 T and 3.0 T MRI scanners using survey sequences, proton density sequences in the coronal and sagittal planes, and VIBE sequences. Using the images of both feet produced by VIBE sequences, the cartilages of the talus and tibia were manually circumscribed using a computer mouse in every third layer, and the volume was calculated. For qualitative assessment, blinded images were submitted to three radiologists with defined standards. The images were scored using a scale from 1 to 5. RESULTS: Cartilage volume: The investigation and examination of the individual cartilage volumes by analysis of variance (ANOVA) showed no significant differences among the three groups. The effect intensities, as calculated by Cohen's d, were right tibia (Tiri) = 2.5, left tibia (Tile) = 2.2, right talus (Tari) = 1.9, and left talus (Tale) = 1.6 in the strenuous sport versus nonstrenuous sport groups; Tiri = 0.8, Tile = 1.2, Tari = 0.4, and Tale = 0.5 in the strenuous sport versus nonathlete groups; and Tiri = 0.3, Tile = 0.2, Tari = 0.7, and Tale = 0.5 in the nonstrenuous sport versus nonathlete groups. Device comparison: In the investigation of each evaluated area on the 1.5 T and 3.0 T MR images by the Wilcoxon matched-pair test, significant differences were found for the cartilage-bone border (KKG = 0.002), cancellous bone (Sp = 0.001), medial ligamentous apparatus (mBa = 0.001), lateral ligamentous apparatus (lBa = 0.001), and adipose tissue (Fg = 0.002). Thus, there were significant differences in the assessment of the 1.5 T MRI and the 3.0 T MRI in all five evaluated areas. CONCLUSION: The study showed no significant difference in the volume of hyaline articular cartilage in the upper ankle joint among the high-performance strenuous DFB athlete, high-performance non-strenuous DSV athlete, and nonathlete groups. The 3.0 Tesla device offers significant advantages in image quality compared to the 1.5 Tesla device.

International Olympic Committee (IOC) consensus paper on sports-related ophthalmology issues in elite sports.

Vision plays an important role in an athletes' success. In sports, nearly 80% of perceptual input is visual, and eye health and sports medicine are closely intertwined fields of utmost importance to athletes. The physical nature of sports activities renders individuals more prone to various eye injuries than the general population. Ocular trauma can lead to lifelong sequelae, and impaired vision requires careful follow-up and management. Apart from injuries, athletes may also experience vision problems that can hamper their performance, including blurred vision, double vision, and light sensitivity. The interdisciplinary nature of sports medicine necessitates collaboration between sports medicine professionals and ophthalmologists. Through such collaborations, athletes can receive appropriate eye care, education on proper eye protection and guidance on adopting good eye health practices. If any inconspicuous symptoms are not detected and treated promptly, athletes may acquire systemic injuries because of defective vision, preventing them from achieving high level athletic performance in competitions. The protection of the elite athlete is the responsibility of all of us in sports medicine. To advance a more unified, evidence-informed approach to ophthalmic health assessment and management in athletes and as relevant for sports medicine physicians, the International Olympic Committee Consensus Group aims for a critical evaluation of the current state of the science and practice of ophthalmologic issues and illness in high-level sports, and present recommendations for a unified approach to this important issue.

[The acute abdomen in children]. / Akutes Abdomen im Kindesalter.

BACKGROUND: Because 8-10% of children in the emergency room present with acute abdominal pain, a systematic work-up is essential to rule out acute abdomen. OBJECTIVES: This article highlights the etiology, symptoms, diagnostic workup, and treatment of acute abdomen in children. MATERIALS AND METHODS: Review of the current literature. RESULTS: Abdominal inflammation, ischemia, bowel and ureteral obstruction, or abdominal bleeding are causes of acute abdomen. Extra-abdominal diseases such as otitis media in toddlers or testicular torsion in adolescent boys can also lead to symptoms of acute abdomen. Abdominal pain, (bilious) vomiting, abdominal guarding, constipation, blood-tinged stools, abdominal bruise marks, and poor condition of the patient with symptoms such as tachycardia, tachypnea, and hypotonia up to shock are leading symptoms of acute abdomen. In some cases, emergent abdominal surgery is needed to treat the cause of the acute abdomen. However, in patients with pediatric inflammatory multisystem syndrome temporarily associated with SARS-CoV­2 infection (PIMS-TS), a new disease causing an acute abdomen, surgical treatment is rarely needed. CONCLUSIONS: Acute abdomen can lead to nonreversible loss of an abdominal organ, such as bowel or ovary, or develop into acute deterioration of the patient's condition up to the state of shock. Therefore, a complete history and thorough physical examination are needed to timely diagnose acute abdomen and initiate specific therapy.

Interstitial cells of Cajal: clinical relevance in pediatric gastrointestinal motility disorders.

Interstitial cells of Cajal (ICCs) are pacemaker cells of gastrointestinal motility that generate and transmit electrical slow waves to smooth muscle cells in the gut wall, thus inducing phasic contractions and coordinated peristalsis. Traditionally, tyrosine-protein kinase Kit (c-kit), also known as CD117 or mast/stem cell growth factor receptor, has been used as the primary marker of ICCs in pathology specimens. More recently, the Ca2+-activated chloride channel, anoctamin-1, has been introduced as a more specific marker of ICCs. Over the years, various gastrointestinal motility disorders have been described in infants and young children in which symptoms of functional bowel obstruction arise from ICC-related neuromuscular dysfunction of the colon and rectum. The current article provides a comprehensive overview of the embryonic origin, distribution, and functions of ICCs, while also illustrating the absence or deficiency of ICCs in pediatric patients with Hirschsprung disease intestinal neuronal dysplasia, isolated hypoganglionosis, internal anal sphincter achalasia, and congenital smooth muscle cell disorders such as megacystis microcolon intestinal hypoperistalsis syndrome.

Tissue Shrinkage of Resected Specimens in Hirschsprung's Disease: Why Pediatric Surgeons Think the Bowel Specimen was Longer Than Indicated in the Pathology Report.

BACKGROUND: Hirschsprung disease (HD) is an aganglionosis of variable length starting at the rectosigmoid colon with surgery as sole therapeutic option. The length of the resected bowel segment is a crucial information for the treating surgeons and influences the prognosis of the patient. It is often artificially altered due to post operative tissue shrinkage. The objective of this study is to quantify the extent tissue shrinkage of HD specimens. MATERIAL AND METHODS: Colorectal HD specimens were measured at the time of surgery and at the time of cut-up, either fresh or after formalin fixation and statistically analyzed. RESULTS: Sixteen colorectal specimens were included. Following formalin fixation the specimen length decreased by 22.7% (P < .001). Without formalin fixation the specimens shrank by an average of 24.9% (P = .05). There was no significant difference in the extent of tissue shrinkage with or without formalin fixation (P = .76). CONCLUSION: This study showed that there is significant tissue shrinkage in HD specimens. The 2 different cohorts revealed that tissue shrinkage is mostly caused by tissue retraction/alteration after organ removal but also to a lesser extent by fixation with formalin. Surgeons and (neuro-)pathologists should be aware of the sizeable shrinking artifact to avoid unnecessary confusion.

Differences in the Outcome of Colonic Atresia with and without Abdominal Wall Defects.

INTRODUCTION: Colonic atresia (CA) is a very rare disease. Two entities of CA can be differentiated: primary CA and CA with abdominal wall defects (AWD). This study aimed to investigate the differences between these two entities, especially for long-term outcomes. MATERIALS AND METHODS: Data from the major health insurance company (AOK) were analyzed. Sixty-two patients with ICD-10 codes Q42.1-2 and Q42.8-9 (atresia of the colon and rectum) who underwent surgery within 10 days after their first admission between 2007 and 2016 were obtained. RESULTS: Twenty-nine patients had an AWD, and 33 patients had primary colonic atresia (PCA). Significant differences between patients with PCA and AWD were found regarding prematurity but not for other concomitant malformations. Ostomy was the initial therapy of choice for 87.9% (29/33) of patients with PCA and 65.5% (19/29) with AWD. Central venous access was significantly more often in patients with AWD. Overall, patients with CA have an excellent short-term outcome. The 1-year mortality was 3% (1/33) in PCA and 6.9% (2/29) in AWD. Delayed management did not lead to higher mortality. Higher number of admission days and higher hospital costs were related to gastrostomy and short bowel in the long term. CONCLUSION: The long-term outcome of CA is related to short bowel and need for initial gastrostomy but not related to AWD, prematurity, or associated anomalies.

Genome-wide identification of disease-causing copy number variations in 450 individuals with anorectal malformations.

Anorectal malformations (ARM) represent a spectrum of rare malformations originating from a perturbated development of the embryonic hindgut. Approximately 60% occur as a part of a defined genetic syndrome or within the spectrum of additional congenital anomalies. Rare copy number variations (CNVs) have been associated with both syndromic and non-syndromic forms. The present study represents the largest study to date to explore the contribution of CNVs to the expression of ARMs. SNP-array-based molecular karyotyping was applied in 450 individuals with ARM and 4392 healthy controls. CNVs were identified from raw intensity data using PennCNV. Overlapping CNVs between cases and controls were discarded. Remaining CNVs were filtered using a stringent filter algorithm of nine filter steps. Prioritized CNVs were confirmed using qPCR. Filtering prioritized and qPCR confirmed four microscopic chromosomal anomalies and nine submicroscopic CNVs comprising seven microdeletions (del2p13.2, del4p16.2, del7q31.33, del9p24.1, del16q12.1, del18q32, del22q11.21) and two microduplications (dup2p13.2, dup17q12) in 14 individuals (12 singletons and one affected sib-pair). Within these CNVs, based on their embryonic expression data and function, we suggest FOXK2, LPP, and SALL3 as putative candidate genes. Overall, our CNV analysis identified putative microscopic and submicroscopic chromosomal rearrangements in 3% of cases. Functional characterization and re-sequencing of suggested candidate genes is warranted.

Hepatoblastoma Cancer Stem Cells Express PD-L1, Reveal Plasticity and Can Emerge upon Chemotherapy.

The biology of cancer stem cells (CSCs) of pediatric cancers, such as hepatoblastoma, is sparsely explored. This is mainly due to the very immature nature of these tumors, which complicates the distinction of CSCs from the other tumor cells. Previously, we identified a CSC population in hepatoblastoma cell lines expressing the CSC markers CD34 and CD90, cell surface Vimentin (csVimentin) and binding of OV-6. In this study, we detected the co-expression of the immune escape factor PD-L1 in the CSC population, whereas the other tumor cells remained negative. FACS data revealed that non-CSCs give rise to CSCs, reflecting plasticity of CSCs and non-CSCs in hepatoblastoma as seen in other tumors. When we treated cells with cisplatin and decitabine, a new CD34+/lowOV-6lowCD90+ population emerged that lacked csVimentin and PD-L1 expression. Expression analyses showed that this new CSC subset shared similar pluripotency and EMT features with the already-known CSCs. FACS results further revealed that this subset is also generated from non-CSCs. In conclusion, we showed that hepatoblastoma CSCs express PD-L1 and that the biology of hepatoblastoma CSCs is of a plastic nature. Chemotherapeutic treatment leads to another CSC subset, which is highly chemoresistant and could be responsible for a poor prognosis after postoperative chemotherapy.

Multidisciplinary Treatment Strategies for Wilms Tumor: Recent Advances, Technical Innovations and Future Directions.

Significant progress has been made in the management of Wilms tumor (WT) in recent years, mostly as a result of collaborative efforts and the implementation of protocol-driven, multimodal therapy. This article offers a comprehensive overview of current multidisciplinary treatment strategies for WT, whilst also addressing recent technical innovations including nephron-sparing surgery (NSS) and minimally invasive approaches. In addition, surgical concepts for the treatment of metastatic disease, advances in tumor imaging technology and potentially prognostic biomarkers will be discussed. Current evidence suggests that, in experienced hands and selected cases, laparoscopic radical nephrectomy and laparoscopic-assisted partial nephrectomy for WT may offer the same outcome as the traditional open approach. While NSS is the standard procedure for bilateral WT, NSS has evolved as an alternative technique in patients with smaller unilateral WT and in cases with imminent renal failure. Metastatic disease of the lung or liver that is associated with WT is preferably treated with a three-drug chemotherapy and local radiation therapy. However, surgical sampling of lung nodules may be advisable in persistent nodules before whole lung irradiation is commenced. Several tumor markers such as loss of heterozygosity of chromosomes 1p/16q, 11p15 and gain of function at 1q are associated with an increased risk of recurrence or a decreased risk of overall survival in patients with WT. In summary, complete resection with tumor-free margins remains the primary surgical aim in WT, while NSS and minimally invasive approaches are only suitable in a subset of patients with smaller WT and low-risk disease. In the future, advances in tumor imaging technology may assist the surgeon in defining surgical resection margins and additional biomarkers may emerge as targets for development of new diagnostic tests and potential therapies.

Genetically Modified Mouse Models of Congenital Diaphragmatic Hernia: Opportunities and Limitations for Studying Altered Lung Development.

Congenital diaphragmatic hernia (CDH) is a relatively common and life-threatening birth defect, characterized by an abnormal opening in the primordial diaphragm that interferes with normal lung development. As a result, CDH is accompanied by immature and hypoplastic lungs, being the leading cause of morbidity and mortality in patients with this condition. In recent decades, various animal models have contributed novel insights into the pathogenic mechanisms underlying CDH and associated pulmonary hypoplasia. In particular, the generation of genetically modified mouse models, which show both diaphragm and lung abnormalities, has resulted in the discovery of multiple genes and signaling pathways involved in the pathogenesis of CDH. This article aims to offer an up-to-date overview on CDH-implicated transcription factors, molecules regulating cell migration and signal transduction as well as components contributing to the formation of extracellular matrix, whilst also discussing the significance of these genetic models for studying altered lung development with regard to the human situation.

Development of a Bowel Management Scoring Tool in Pediatric Patients with Constipation.

OBJECTIVE: To develop a reliable and valid scoring tool, the Pediatric Bowel Management Scoring Tool (PBMST), to better guide management of constipation in pediatric patients. STUDY DESIGN: The project comprised 2 stages, development of the questionnaire and construction of the bowel management score. Two questionnaires were created, one for children aged 8-18 years to self-report and one parent proxy-report for children aged 4-8 years. Questions regarding physical symptoms (n = 6), emotional aspects (n = 2), social activities/school (n = 1), and treatment (n = 1) were included. Patients (or parents of patients) with symptoms of constipation completed the questionnaire. The reproducibility of each question was computed using the Cohen weighted kappa coefficient (κ). A bowel management score was developed using logistic regression analysis, assessing the associations between the questions and impact on self-reported quality of life (QoL). Questions with adequate reproducibility and significantly associated with QoL were incorporated into the score. RESULTS: The questionnaire was completed by 385 patients. Six questions met the inclusion criteria and were incorporated into the score: stool shape (range, 0-3 points), anorectal pain (0-4 points), abdominal pain (0-3 points), frequency of fecal incontinence (0-3 points), assistance of caregivers (0-3 points), and interference with social activities (0-6 points). Differences in bowel management scores among patients reporting no, little, some, or major impact on QoL were statistically significant (P < .001). CONCLUSIONS: The newly developed and validated PBMST is a reliable tool for evaluating bowel management strategies in children with constipation.

Prenatal Detection of Congenital Duodenal Obstruction-Impact on Postnatal Care.

BACKGROUND: Duodenal obstruction is a rare cause of congenital bowel obstruction. Prenatal ultrasound could be suggestive of duodenal atresia if polyhydramnios and the double bubble sign are visible. Prenatal diagnosis should prompt respective prenatal care, including surgery. The aim of this study was to investigate the rate and importance of prenatally diagnosed duodenal obstruction, comparing incomplete and complete duodenal obstruction. METHODS: A retrospective, single-center study was performed using data from patients operated on for duodenal obstruction between 2004 and 2019. Prenatal ultrasound findings were obtained from maternal logbooks and directly from the investigating obstetricians. Postnatal data were obtained from electronic charts, including imaging, operative notes and follow-up. RESULTS: A total of 33/64 parents of respective patients agreed to provide information on prenatal diagnostics. In total, 11/15 patients with complete duodenal obstruction and 0/18 patients with incomplete duodenal obstruction showed typical prenatal features. Prenatal diagnosis prompted immediate surgical treatment after birth. CONCLUSION: Prenatal diagnosis of congenital duodenal obstruction is only achievable in cases of complete congenital duodenal obstruction by sonographic detection of the pathognomonic double bubble sign. Patients with incomplete duodenal obstruction showed no sign of duodenal obstruction on prenatal scans and thus were diagnosed and treated later.

Operative Volume of Newborn Surgery in German University Hospitals: High Volume Versus Low Volume Centers.

INTRODUCTION: Adequate patient volume is essential for the maintenance of quality, meaningful research, and training of the next generation of pediatric surgeons. The role of university hospitals is to fulfill these tasks at the highest possible level. Due to decentralization of pediatric surgical care during the last decades, there is a trend toward reduction of operative caseloads. The aim of this study was to assess the operative volume of the most relevant congenital malformations at German academic pediatric surgical institutions over the past years. METHODS: Nineteen chairpersons representing university-chairs in pediatric surgery in Germany submitted data on 10 index procedures regarding congenital malformations or neonatal abdominal emergencies over a 3-year period (2015 through 2017). All institutions were categorized according to the total number of respective cases into "high," "medium," and "low" volume centers by terciles. Some operative numbers were verified using data from health insurance companies, when available. Finally, the ratio of cumulative case load versus prevalence of the particular malformation was calculated for the study period. RESULTS: From 2015 through 2017, a total 2,162 newborns underwent surgery for congenital malformations and neonatal abdominal emergencies at German academic medical centers, representing 51% of all expected newborn cases nationwide. The median of cases per center within the study period was 101 (range 18-258). Four institutions (21%) were classified as "high volume" centers, four (21%) as "medium volume" centers, and 11 (58%) as "low volume" centers. The proportion of patients operated on in high-volume centers varied per disease category: esophageal atresia/tracheoesophageal fistula: 40%, duodenal atresia: 40%, small and large bowel atresia: 39%, anorectal malformations: 40%, congenital diaphragmatic hernia: 56%, gastroschisis: 39%, omphalocele: 41%, Hirschsprung disease: 45%, posterior urethral valves: 39%, and necrotizing enterocolitis (NEC)/focal intestinal perforation (FIP)/gastric perforation (GP): 45%. CONCLUSION: This study provides a national benchmark for neonatal surgery performed in German university hospitals. The rarity of these cases highlights the difficulties for individual pediatric surgeons to gain adequate clinical and surgical experience and research capabilities. Therefore, a discussion on the centralization of care for these rare entities is necessary.

Outcome of esophageal atresia: inborn versus outborn patients.

Esophageal atresia (EA) is a rare congenital disease which is usually not of the detected prenatally. Due to the lack of prenatal diagnosis, some newborns with EA are born outside of specialized centers. Nevertheless, centralized care of EA has been proposed, even if a clear volume-outcome association in EA management remains unconfirmed. Furthermore, whether outcomes differ between outborn and inborn patients with EA has not been systematically investigated. Therefore, this single-center, retrospective study aimed to investigate EA management and outcomes with a special focus on inborn versus outborn patients. The following data were extracted from the medical records of infants with EA from 2009 to 2019: EA type, associated anomalies, complications, and long-term outcome. Patients were allocated into inborn and outborn groups. Altogether, 57 patients were included. Five patients were excluded (referral before surgery, loss of data, death before surgery [n = 1], and incorrect diagnosis [diverticulum, n = 1]). Among all patients, the overall survival rate was 96%, with no mortalities among outborn patients. The overall hospitalization period was shorter for outborn patients. The median follow-up durations were 3.8 years and 3.2 years for inborn and outborn patients, respectively. Overall, 15% of patients underwent delayed primary anastomosis (long-gap atresia [n = 4] and other reasons [n = 4]). Early complications included three anastomotic leakages and one post-operative fistula; 28% of patients developed strictures, which required dilatation, and 38% of patients showed relevant gastroesophageal reflux, which required fundoplication, without any differences between the groups. The two groups had comparable low mortality and expected high morbidity with no significant differences in outcome. The outborn group showed nonsignificant trends toward lower morbidity and shorter hospitalization periods, which might be explained by the overall better clinical status.

Incidence of penalty corner injuries in international field hockey.

Field hockey penalty corners (PCs) put players at potential risk for injuries. This study evaluated the incidence of PC-related injuries with special regards to head injuries. Video sequences provided by the Fédération Internationale de Hockey (FIH) of 295 matches in 11 elite field hockey tournaments (2015-2016) were analysed for overall injuries and PC-related injuries in detail. In total, 13.9% of all match injuries (49/352 injuries) occurred in relation to a PC, accounting for 7.1 PC-related injuries per 1000 player match hours (95% CI 4.4-9.9). There were 11 head injuries afflicting six defenders and five attackers. One head injury was related to a direct hit by a ball (drag flick). This study provides the first data on PC-related injuries in elite field hockey. The recorded numbers and mechanisms of PC-related injuries should be used as a baseline for further studies and potential rule adaptations.