The Management of Post-appendectomy Abscess in Children; A Historical Cohort Study and Update of the Literature.

Introduction: Recent studies have shown that specific cases of post-appendectomy abscess (PAA) in children could be treated conservatively. However, due to the lack of high-quality evidence, choice of treatment still depends on preferences of the treating surgeon, leading to heterogeneity in clinical practice. Therefore, we aimed to provide an update of recent literature on the management of PAA in children and subsequently evaluate the outcomes of a large multicenter cohort of children treated for PAA. Methods: A literature search was performed in Pubmed and Embase, selecting all randomized controlled trials, prospective and retrospective cohort studies, and case series published from 2014 and onward and reporting on children (<18 years) treated for a PAA. Subsequently, a historical cohort study was performed, including all children (<18 years) treated for a radiologically confirmed PAA between 2014 and 2021 in a tertiary referral center and two large peripheral centers. Medical charts were reviewed to compare non-invasive (i.e., antibiotics) and invasive (i.e., drainage procedures) treatment strategies. Primary outcome was the success rate of treatment, defined as no need for further interventions related to PAA or its complications. Results: The search yielded 1,991 articles, of which three were included. Treatment success ranged between 69-88% and 56-100% for non-invasive and invasive strategies, respectively. Our multicenter cohort study included 70 children with a PAA, of which 29 (41%) were treated non-invasively and 41 (59%) invasively. In the non-invasive group, treatment was effective in 21 patients (72%) compared to 25 patients (61%) in the invasive group. Non-invasive treatment was effective in 100% of unifocal small (<3 cm) and 80% of unifocal medium size PAA (3-6 cm), but not effective for multiple abscesses. Conclusion: Non-invasive treatment of especially unifocal small and medium size (<6 cm) PAA in children seems to be safe and effective. Based on these results, a standardized treatment protocol was developed. Prospective validation of this step-up approach-based treatment protocol is recommended.

Do We Need to Stabilize All Reduced Metaphyseal Both-bone Forearm Fractures in Children with K-wires?

BACKGROUND: Short-term follow-up studies have shown that reduced metaphyseal both-bone forearm fractures in children should be treated with K-wires to prevent redisplacement and inferior functional results. Minimum 5-year follow-up studies are limited. Range of motion, patient-reported outcome measures, and radiographic parameters at minimum 5-year follow-up should be evaluated because they could change insights into how to treat pediatric metaphyseal forearm fractures. QUESTIONS/PURPOSES: (1) Does K-wire stabilization of reduced metaphyseal both-bone forearm fractures in children provide better forearm rotation at minimum 5-year follow-up? (2) Do malunions (untreated redisplaced fractures) of reduced metaphyseal both-bone forearm fractures in children induce worse functional results? (3) Which factors lead to limited forearm rotation at minimum 5-year follow-up? METHODS: We analyzed the extended minimum 5-year follow-up of a randomized controlled trial in which children with a reduced metaphyseal both-bone forearm fracture were randomized to either an above-elbow cast (casting group) or fixation with K-wires and an above-elbow cast (K-wire group). Between January 2006 and December 2010, 128 patients were included in the original randomized controlled trial: 67 in the casting group and 61 in the K-wire group. For the current study, based on an a priori calculation, it was determined that, with an anticipated mean limitation in prosupination (forearm rotation) of 7° ± 7° in the casting group and 3° ± 5° in the K-wire group, a power of 80% and a significance of 0.05, the two groups should consist of 50 patients each. Between January 2014 and May 2016, 82% (105 of 128) of patients were included, with a mean follow-up of 6.8 ± 1.4 years: 54 in the casting group and 51 in the K-wire group. At trauma, patients had a mean age of 9 ± 3 years and had mean angulations of the radius and ulna of 25° ± 14° and 23° ± 18°, respectively. The primary result was limitation in forearm rotation. Secondary outcome measures were radiologic assessment, patient-reported outcome measures (QuickDASH and ABILHAND-kids), handgrip strength, and VAS score for cosmetic appearance. Assessments were performed by the first author (unblinded). Multivariable logistic regression analysis was performed to analyze which factors led to a clinically relevant limitation in forearm rotation. RESULTS: There was a mean limitation in forearm rotation of 5° ± 11° in the casting group and 5° ± 8° in the K-wire group, with a mean difference of 0.3° (95% CI -3° to 4°; p = 0.86). Malunions occurred more often in the casting group than in the K-wire group: 19% (13 of 67) versus 7% (4 of 61) with an odds ratio of 0.22 for K-wiring (95% CI 0.06 to 0.80; p = 0.02). In patients in whom a malunion occurred (malunion group), there was a mean limitation in forearm rotation of 6° ± 16° versus 5° ± 9° in patients who did not have a malunion (acceptable alignment group), with a mean difference 0.8° (95% CI -5° to 7°; p = 0.87). Factors associated with a limited forearm rotation ≥ 20° were a malunion after above-elbow casting (OR 5.2 [95% CI 1.0 to 27]; p = 0.045) and a refracture (OR 7.1 [95% CI 1.4 to 37]; p = 0.02). CONCLUSION: At a minimum of 5 years after injury, in children with a reduced metaphyseal both-bone forearm fracture, there were no differences in forearm rotation, patient-reported outcome measures, or radiographic parameters between patients treated with only an above-elbow cast compared with those treated with additional K-wire fixation. Redisplacements occurred more often if treated by an above-elbow cast alone. If fracture redisplacement is not treated promptly, this leads to a malunion, which is a risk factor for a clinically relevant (≥ 20°) limitation in forearm rotation at minimum 5-year follow-up. Children with metaphyseal both-bone forearm fractures can be treated with closed reduction and casting without additional K-wire fixation. Nevertheless, a clinician should inform parents and patient about the high risk of fracture redisplacement (and therefore malunion), with risk for limited forearm rotation if left untreated. Weekly radiographic monitoring is essential. If redisplacement occurs, remanipulation and fixation with K-wires should be considered based on gender, age, and direction of angulation. Future research is required to establish the influence of (skeletal) age, gender, and the direction of malunion angulation on clinical outcome. LEVEL OF EVIDENCE: Level I, therapeutic study.

The Dutch Incidence of Infantile Hypertrophic Pyloric Stenosis and the Influence of Seasons.

INTRODUCTION: Studies report contradicting results on the incidence of infantile hypertrophic pyloric stenosis (IHPS) and its association with seasons. We aim to assess the IHPS incidence in the Netherlands and to determine whether seasonal variation is present in a nationwide cohort. MATERIALS AND METHODS: All infants with IHPS hospitalized in the Netherlands between 2007 and 2017 were included in this retrospective cohort study. Incidence rates per 1,000 livebirths (LB) were calculated using total number of LB during the matched month, season, or year, respectively. Seasonal variation based on month of birth and month of surgery was analyzed using linear mixed model and one-way ANOVA, respectively. RESULTS: A total of 2,479 infants were included, of which the majority was male (75.9%). Median (interquartile range) age at surgery was 34 (18) days. The average IHPS incidence rate was 1.28 per 1,000 LB (variation: 1.09-1.47 per 1,000 LB). We did not find a conclusive trend over time in IHPS incidence. Differences in incidence between season of birth and season of surgery were not significant (p = 0.677 and p = 0.206, respectively). CONCLUSION: We found an average IHPS incidence of 1.28 per 1,000 LB in the Netherlands. Our results showed no changing trend in incidence and no seasonal variation.

Angular malalignment as cause of limitation of forearm rotation: an analysis of prospectively collected data of both-bone forearm fractures in children.

INTRODUCTION: Although limitation of pronation/supination following both-bone forearm fractures in children is often attributed to an angular malunion, no clinical study has compared pronation/supination and angular malalignment of the same child by analysis of prospectively collected clinical data. AIM: The purpose of this trial is to explore whether limitation of pronation/supination can be predicted by the degree of angular malalignment in children who sustained a both-bone forearm fracture. METHODS: In four Dutch hospitals, children aged ≤16 years with a both-bone forearm fracture were prospectively followed up consecutive children for 6-9 months. At the final follow-up, pronation/supination and angular malunion on radiographs were determined. RESULTS: Between January 2006 and August 2010, a total of 410 children were prospectively followed up, of which 393 children were included for analysis in this study. The mean age of the children was 8.0 (±3.5) years, of which 63% were male and 40% fractured their dominant arm. The mean time to final examination was 219 (±51) days. Children with a metaphyseal both-bone fracture of the distal forearm with an angular malalignment of ≤15° had a 9-13% chance of developing a clinically relevant limitation (i.e., <50° of pronation and/or supination), while children with an angular malalignment of ≥16° had a 60% chance. Children with diaphyseal both-bone forearm fractures with ≤5° of angular malalignment had a 13% chance of developing a clinically relevant limitation, which showed no significant increase with a further increase of angular malalignment. CONCLUSIONS: Children who sustained a both-bone forearm fracture localised in the distal metaphysis have a higher chance of developing a clinically relevant limitation of forearm rotation in case of a more severe angular malalignment, while children with a diaphyseal both-bone forearm fracture had a moderate chance of limitation, irrespective of the severity of the angular malalignment.

Three-dimensional imaging of children with severe limitation of pronation/supination after a both-bone forearm fracture.

INTRODUCTION: Although both-bone forearm fractures in children may result in severe limitation of forearm rotation, finding the cause remains a diagnostic challenge. This study tries to evaluate the role of rotational malunion, bony impingement and contractures of the interosseous membrane. PATIENTS AND METHODS: Children (5-16 years) who suffered from a both-bone forearm fracture in diaphysis or distal metaphysis with a limitation of pronation/supination ≥40° at ≥6 months after trauma were included for analysis with conventional radiographs, computed tomography (CT) and magnetic resonance imaging (MRI). RESULTS: A total of 410 children with a both-bone forearm fracture were prospectively followed in four Dutch hospitals. At a median of 205 days, 7.3 % suffered from a limitation of pronation/supination ≥40°. 14 children were included (median limitation of 40°) and the radiographs revealed a median maximum angular malunion of 16°. CT analysis showed rotational malunion of both radius (median 19°) and ulna (median 9°). MRI analysis revealed neither bony impingement nor contractures of the interosseous membrane. CONCLUSIONS: Three-dimensional imaging of children with a severe limitation of pronation/supination after a both-bone forearm fracture revealed rotational malunions of both radius and ulna without bony impingement or soft tissue contractures. LEVEL OF EVIDENCE: Prospective multicenter study, Level 2.

Which factors affect limitation of pronation/supination after forearm fractures in children? A prospective multicentre study.

INTRODUCTION: Both-bone forearm fractures in children frequently result in a limitation of pronation/supination, which hinders daily activities. The purpose of this prospective multicentre study was to investigate which clinical factors are related to the limitation of pronation/supination in children with a both-bone forearm fracture. METHODS: In four Dutch hospitals, consecutive children (<16 years) who sustained a both-bone forearm fracture were included. Children were followed up for 6-9 months and data from questionnaires, physical examination and X-rays were collected. Univariate and multivariate logistic regression analyses were used to assess the relationship between limitation of pronation/supination (≥20°) and several clinical factors. RESULTS: A group of 410 children with both-bone forearm fractures were included, of which 10 children missed the final examination (follow-up rate of 97.6%). We found that a re-fracture (odds ratio (OR) 11.7, 95% confidence interval (CI) 1.2; 118.5), a fracture in the diaphysis (OR 3.3, 95% CI 1.4; 7.9) and less physiotherapy during follow-up (OR 0.90, 95% CI 0.82; 0.98) were independently associated with a limitation of pronation/supination of 20° or more. CONCLUSIONS: These findings imply that a re-fracture and a diaphyseal located fracture were associated independently of each other with a limitation of pronation/supination in children with a both-bone forearm fracture. Furthermore, in children with severe limitation extensive physiotherapy is associated with better functional outcome.

Conversion to below-elbow cast after 3 weeks is safe for diaphyseal both-bone forearm fractures in children.

BACKGROUND: It is unclear whether it is safe to convert above-elbow cast (AEC) to below-elbow cast (BEC) in a child who has sustained a displaced diaphyseal both-bone forearm fracture that is stable after reduction. In this multicenter study, we wanted to answer the question: does early conversion to BEC cause similar forearm rotation to that after treatment with AEC alone? CHILDREN AND METHODS: Children were randomly allocated to 6 weeks of AEC, or 3 weeks of AEC followed by 3 weeks of BEC. The primary outcome was limitation of pronation/supination after 6 months. The secondary outcomes were re-displacement of the fracture, limitation of flexion/extension of the wrist and elbow, complication rate, cast comfort, complaints in daily life, and cosmetics of the fractured arm. RESULTS: 62 children were treated with 6 weeks of AEC, and 65 children were treated with 3 weeks of AEC plus 3 weeks of BEC. The follow-up rate was 60/62 and 64/65, respectively with a mean time of 6.9 (4.7-13) months. The limitation of pronation/supination was similar in both groups (18 degrees for the AEC group and 11 degrees for the AEC/BEC group). The secondary outcomes were similar in both groups, with the exception of cast comfort, which was in favor of the AEC/BEC group. INTERPRETATION: Early conversion to BEC cast is safe and results in greater cast comfort.

Early conversion to below-elbow cast for non-reduced diaphyseal both-bone forearm fractures in children is safe: preliminary results of a multicentre randomised controlled trial.

INTRODUCTION: This multicentre randomised controlled trial was designed to explore whether 6 weeks above-elbow cast (AEC) or 3 weeks AEC followed by 3 weeks below-elbow cast (BEC) cause similar limitation of pronation and supination in non-reduced diaphyseal both-bone forearm fractures in children. MATERIALS AND METHODS: Children were randomly allocated to 6 weeks AEC or to 3 weeks AEC followed by 3 weeks BEC. The primary outcome was limitation of pronation and supination after 6 months. The secondary outcomes were re-displacement of the fracture, complication rate, limitation of flexion and extension of wrist and elbow, cast comfort, cosmetics, complaints in daily life and assessment of radiographs. RESULTS: A group of 23 children was treated with 6 weeks AEC and 24 children with 3 weeks AEC and 3 weeks BEC. The follow-up rate was 98 % with a mean follow-up of 7.0 months. The mean limitation of pronation and supination was 23.3 ± 22.0 for children treated with AEC and 18.0 ± 16.9 for children treated with AEC and BEC. The other study outcomes were similar in both groups. CONCLUSIONS: Early conversion to BEC is safe in the treatment of non-reduced diaphyseal both-bone forearm fractures in children. LEVEL OF EVIDENCE: Multicentre randomised controlled trial, Level II.

Single-bone intramedullary fixation of unstable both-bone diaphyseal forearm fractures in children leads to increased re-displacement: a multicentre randomised controlled trial.

INTRODUCTION: Both-bone diaphyseal forearm fractures in children can be stabilised without cast by a flexible intramedullary nail in both the radius and the ulna. Adequate results with single-bone fixation combined with a complementary cast are also reported. However, because those results are based on a selection of children, this trial investigates whether single-bone intramedullary fixation, compared with both-bone intramedullary fixation, results in similar pronation and supination in children with an unstable diaphyseal both-bone forearm fracture. MATERIALS AND METHODS: In four Dutch hospitals, 24 consecutive children aged <16 years with a displaced unstable both-bone diaphyseal forearm fracture were randomly allocated to single-bone or both-bone intramedullary fixation. Primary outcome was limitation of pronation and supination 9 months after initial trauma. Secondary outcomes were limitation of flexion/extension of wrist/elbow, complication rate, operation time, cosmetics of the fractured arm, complaints in daily life, and assessment of radiographs. RESULTS: Between January 2006 and August 2010, 11 children were randomised to single-bone fixation and 13 to both-bone fixation. In the both-bone fixation group, two fractures were stabilized by only one nail. In both groups, median limitation of pronation/supination at 9-month follow-up was 5°-10°. In both groups operation time was similar but in the single-bone fixation group cast immobilisation was longer (median of 37 vs. 28 days). In four children, re-displacement of the fracture occurred in those fractures without an intramedullary nail. CONCLUSIONS: These results caution against the use of single-bone fixation in all both-bone forearm fractures. This method may lead to increased re-displacement and reduced clinical results.

Re-displacement of stable distal both-bone forearm fractures in children: a randomised controlled multicentre trial.

INTRODUCTION: Displaced metaphyseal both-bone fractures of the distal forearm are generally reduced and stabilised by an above-elbow cast (AEC) with or without additional pinning. The purpose of this study was to find out if re-displacement of a reduced stable metaphyseal both-bone fracture of the distal forearm in a child could be prevented by stabilisation with Kirschner wires. METHODS: Consecutive children aged <16 years with a displaced metaphyseal both-bone fracture of the distal forearm (n = 128) that was stable after reduction were randomised to AEC with or without percutaneous fixation with Kirschner wires. The primary outcome was re-displacement of the fracture. RESULTS: A total of 67 children were allocated to fracture reduction and AEC and 61 to reduction of the fracture, fixation with Kirschner wires and AEC. The follow-up rate was 96% with a mean follow-up of 7.1 months. Fractures treated with additional pinning showed less re-displacement (8% vs. 45%), less limitation of pronation and supination (mean limitation 6.9 (± 9.4)° vs. 14.3 (± 13.6)°) but more complications (14 vs. 1). CONCLUSIONS: Pinning of apparent stable both-bone fractures of the distal forearm in children might reduce fracture re-displacement. The frequently seen complications of pinning might be reduced by a proper surgical technique.

Below-elbow cast for metaphyseal both-bone fractures of the distal forearm in children: a randomised multicentre study.

INTRODUCTION: Minimally displaced metaphyseal both-bone fractures of the distal forearm in children are often treated with an above-elbow cast (AEC). Treatment with a below-elbow cast (BEC) could give more comfort, but might lead to fracture displacement reducing pronation and supination. Because this has not been systematically investigated, we set up a randomised multicentre study. The purpose of this study was to find out whether BEC causes equal limitation of pronation and supination but with higher comfort level, compared with AEC. PATIENTS AND METHODS: In four hospitals, consecutive children aged<16 (mean 7.1) years with a minimally displaced metaphyseal both-bone fracture of the distal forearm were randomised to 4 weeks BEC (n=35) or 4 weeks AEC (n=31). Primary outcome was limitation of pronation and supination 6 months after initial trauma. The secondary outcomes were cast comfort, limitation of flexion/extension of wrist/elbow, complications, cosmetics, complaints, and radiological assessment. RESULTS: A group of 35 children received BEC and 31 children received AEC. All children attended for the final examination at a mean follow-up of 7.0 months (range 5.0-11.6 months). Limitation of pronation and supination 6 months after initial trauma showed no significant difference between the two groups [4.4° (± 5.8) for BEC and 5.8° (± 9.8) for AEC]. Children treated with BEC had significantly higher cast comfort on a visual analogue scale [5.6 (± 2.7) vs. 8.4 (± 1.4)] and needed significantly less help with dressing (8.2 days vs. 15.1 days). Six complications occurred in the BEC group and 14 in the AEC group. Other secondary outcomes were similar between the two groups. CONCLUSIONS: Children with minimally displaced metaphyseal both-bone fractures of the distal forearm should be treated with a below-elbow cast.

[Intestinal duplication cyst in children: laparoscopically assisted resection is preferred]. / Duplicatiecyste van de darm bij kinderen.

A 5-year-old boy was seen for a second opinion as he had episodes of severe abdominal pain and a variably distended abdomen. Ultrasonography showed a suspected duplication cyst of the terminal ileum. A laparoscopically assisted resection was performed. Histology confirmed the diagnosis of a duplication cyst. A few months later a 10-year-old boy presented with a history of abdominal pain, diarrhoea and vomiting. Abdominal ultrasonography showed an intussusception halfway up the transverse colon where a cyst was seen with a fluid level. The intussusception was reduced during laparoscopy and resection of the duplication cyst of the ileum was performed. Although intestinal duplication cysts are rare (prevalence 1:4500), it is important to know they exist. Laparoscopically assisted resection is an elegant way of treating duplication cysts in children.

Pronation and supination after forearm fractures in children: Reliability of visual estimation and conventional goniometry measurement.

BACKGROUND: Forearm fractures are common amongst children and often result in limited rotational function. In daily practice, pronation and supination of the arm are often visually estimated or measured using a conventional goniometer. The aim of this study was to compare the reliability of these two methods in paediatric patients who had previously sustained a forearm fracture. METHODS: Intra- and interrater reliability of visual estimation and conventional goniometry were determined in 47 children who had previously sustained a forearm fracture. RESULTS: Intra- and interrater reliability of visual estimation and conventional goniometry was fair to excellent, with intraclass correlation coefficients (ICCs) ranging between 0.75 and 0.94. In addition, the overall goniometer data consistently showed lower smallest detectable differences (SDDs) compared to the visual estimation data, also indicating better reliability for the goniometer method. CONCLUSIONS: A conventional goniometer is an easy, fast and reliable method to determine the pronation and supination in a child who had sustained a forearm fracture. If an uncooperative child hinders the measurement, visual estimation is a good second choice. Measurements are more reliable when repeated by the same professional.

US examination of the appendix in children with suspected appendicitis: the additional value of secondary signs.

This study evaluated the additional value of secondary signs in the diagnosing of appendicitis in children with ultrasound. From May 2005 to June 2006, 212 consecutive paediatric patients with suspected appendicitis were examined. Ultrasonographic depiction of the appendix was classified into four groups: 1, normal appendix; 2, appendix not depicted, no secondary signs of appendicitis; 3, appendix not depicted with one of the following secondary signs: hyperechoic mesenteric fat, fluid collection, local dilated small bowel loop; 4, depiction of inflamed appendix. We classified 96 patients in group 1, 41 in group 2, 13 in group 3, and 62 in group 4. Prevalence of appendicitis was 71/212 (34%). Negative predictive values of groups 1 and 2 were 99% and 100%, respectively. Positive predictive values of groups 3 and 4 were 85% and 95%, respectively. In groups 3 and 4, hyperechoic mesenteric fat was seen in 73/75 (97.3%), fluid collections and dilated bowel loops were seen in 12/75 (16.0%) and 5/75 (6.6%), respectively. This study shows that in case of non-visualization of the appendix without secondary signs, appendicitis can be safely ruled out. Furthermore, secondary signs of appendicitis alone are a strong indicator of acute appendicitis.

Can pyloromyotomy for infantile hypertrophic pyloric stenosis be performed in any hospital? Results from two teaching hospitals.

In order to document the incidence of perioperative complications in patients with infantile hypertrophic pyloric stenosis, a descriptive cohort study was performed in two teaching hospitals in the Netherlands. One hospital specialized in pediatric surgery and the other was a general surgery teaching hospital. All consecutive infants who underwent pyloromyotomy for the diagnosis hypertrophic pyloric stenosis in both hospitals between 1998 and 2002 were included. The children were diagnosed and treated according to a standard protocol. From all charts, complications durante- and post-operationem were recorded. A total of 256 pyloromyotomies were performed. Registered perioperative complications were duodenal mucosal perforation (n=6; 2%). Perioperatively unrecognized duodenal mucosal perforation occurred four times (1%). One re-operation was performed for an incomplete pyloromyotomy (0.3%). Persistent vomiting after the operation occurred in 18 children (7%). A large majority of postoperative complications were wound infections (n=16; 6%), 12 after right upper quadrant incision and 4 after umbilical incision; most of them were treated with antibiotics and/or incision for drainage of an abscess. An incisional hernia occurred four times. Prolonged vomiting was the only postoperative complication that differed significantly between the two teaching hospitals. The overall percentages of complications were equal to complication rates in literature, and since there were no extensive differences in major complications between the two teaching hospitals in this study, we can conclude that pyloromyotomy can be performed safely in specialized centers and in general centers provided with a multidisciplinary team.