A New Bioactive Fibrin Formulation Provided Superior Cartilage Regeneration in a Caprine Model.

The effective and long-term treatment of cartilage defects is an unmet need among patients worldwide. In the past, several synthetic and natural biomaterials have been designed to support functional articular cartilage formation. However, they have mostly failed to enhance the terminal stage of chondrogenic differentiation, leading to scar tissue formation after the operation. Growth factors substantially regulate cartilage regeneration by acting on receptors to trigger intracellular signaling and cell recruitment for tissue regeneration. In this study, we investigated the effect of recombinant insulin-like growth factor 1 (rIGF-1), loaded in fibrin microbeads (FibIGF1), on cartilage regeneration. rIGF-1-loaded fibrin microbeads were injected into full-thickness cartilage defects in the knees of goats. The stability, integration, and quality of tissue repair were evaluated at 1 and 6 months by gross morphology, histology, and collagen type II staining. The in vivo results showed that compared to plain fibrin samples, particularly at 6 months, FibIGF1 improved the functional cartilage formation, confirmed through gross morphology, histology, and collagen type II immunostaining. FibIGF1 could be a promising candidate for cartilage repair in the clinic.

[Pédiatrie - Internal lengthening nails: a novel method of lower limb reconstruction in children]. / Pédiatrie - Clous d'allongement internes : nouvelle méthode de reconstruction des membres inférieurs.

Intramedullary lengthening nails for lower limb reconstruction in children are a rapidly growing field and represent an alternative to external fixators. Today, two types of intramedullary lengthening nails are used: motorized (FITBONE) and magnetically driven (PRECISE) bone lengthening nails. Indications for limb lengthening nails are: 1) Significant lower limb length discrepancy; 2) Short stature and deformities due to musculoskeletal or dysplastic syndromes; 3) Constitutional short stature. Intramedullary lengthening surgery is challenging and represents a safe and reliable mode of treatment in patients under 18 years of age with an excellent reported outcome.

Les clous d'allongement intramédullaires pour la reconstruction des membres inférieurs chez les enfants sont un domaine en plein essor et représentent une alternative aux fixateurs externes. Aujourd'hui, 2 types de clous d'allongement intramédullaires sont utilisés : les clous d'allongement osseux motorisés (FITBONE) et à entraînement magnétique (PRECISE). Les indications pour les clous d'allongement des membres sont les suivantes : a) inégalité significative de longueur des membres inférieurs ; b) petite taille et déformations dues à des syndromes musculosquelettiques ou à des dysplasies et c) petite taille constitutionnelle. La chirurgie d'allongement intramédullaire est exigeante et représente un mode de traitement sûr et fiable chez les moins de 18 ans, avec un excellent résultat rapporté par les patients.

Myositis ossificans in the pediatric population: a systematic scoping review.

Introduction: Circumscribed or pseudomalignant myositis ossificans (MO) is a rare and benign condition characterized by heterotopic bone formation in soft tissues. The clinical presentation of MO, imaging investigations, histological findings, and treatment strategies are unclear, especially in the pediatric population. Materials and methods: A literature search was conducted in PubMed, Scopus, and Google Scholar electronic databases to identify original articles and reviews in English or French of traumatic and non-traumatic MO. Studies were selected by 2 independent reviewers following the PRISMA recommendation and descriptive data were extracted. We harvest in each case the sex, age at diagnosis, location, presence of initial trauma, pre-emptive diagnosis, modalities of imagery used, realized biopsy, treatment performed, and type of follow-up. Results: Sixty pediatric cases of MO were identified between 2002 and 2023. Twenty-three patients (38.3%) were diagnosed with idiopathic/pseudomalignant and 37 patients (61.7%) with circumscribed. The mean age at diagnosis was 9.5 years (range 0.2-17 years), with a male-to-female ratio of 1:1. The initial pre-emptive diagnosis was neoplasia in 13 patients (21.7%). The biopsy was percutaneous in 9 patients (15%) and incisional in 7 patients (11.7%). Histological analysis was achieved in 35 cases (57%). Surgical excision was the first line treatment in 46.7% of patients, and non-surgical in the remaining patients. The follow-up strategy was clinical in 16 patients (26.7%) or based on imaging investigation in 23 patients (38.3%). Discussion: Although MO in children is described as a rare pathology, identifying the benignity of the condition is essential to avoid unnecessary invasive treatment and to avoid delaying the treatment of a potentially life-threatening entity. It seems that there is no consensus established concerning the proper imaging for diagnosis. Clinicians should acknowledge that the absence of a triggering trauma tends to direct the investigation and the management toward a surgical attitude. Conservative management is key, however, surgical excision can be proposed on matured lesions on a case-by-case basis. The absence of recurrence is not excluded. Therefore, a close clinical follow-up is suggested for all cases. The true benefit of a radiological is questioned in a question known to be self-resolving.

Diagnostic Utility of Synovial Fluid Cell Counts and CRP in Pediatric Knee Arthritis: A 10-Year Monocentric, Retrospective Study.

BACKGROUND: Orthopedic surgeons often use the intra-articular white blood counts (WBCs) and the percentage of polymorphonuclear cells (PMN) in the diagnosis of an acute swollen and painful knee joint in children. Today, there is no established threshold for the synovial WBC, and their differentiation, as indicative of native joint knee bacterial arthritis. We determine the sensitivity and specificity of synovial WBCs and PMN percentages in the prediction of a community-acquired, acute bacterial native joint septic arthritis (SA) in the pediatric population. METHODS: A retrospective study on healthy children 0-16 years of age who underwent knee joint aspiration for a community-acquired, acute irritable knee effusion in our tertiary-care children's hospital between May 2009 and April 2019 was conducted. We divided the study population into two groups according to the detection of bacterial arthritis in the synovial fluid (bacterial arthritis versus its absence) and compared the intra-articular leukocyte and C-reactive protein (CRP) levels. RESULTS: Overall, we found a statistically significant difference regarding the total CRP (p = 0.017), leukocyte or PMN counts (p ≤ 0.001 in favor of a bacterial arthritis). In contrast, the percentage of the neutrophils was not determinant for the later confirmation of bacterial pathogens, and we were unable to establish diagnostically determining minimal thresholds of the intra-articular CRP and leukocyte levels. CONCLUSIONS: This pilot study suggests that either the leukocyte or PMN counts may be associated with a bacterial origin of knee arthritis in children. We plan a larger prospective interventional study in the future to confirm these findings including the investigation of other joint aspirate biomarkers.

Comparison of treatment outcomes of stable and unstable developmental dysplasia of the hip with the Tübingen splint.

Background: The Tübingen splint was initially developed for the treatment of stable developmental hip dysplasia (DDH). Later on, some authors expanded its include for the treatment of unstable DDH, but there remain some controversies in the literature. This study aims to compare the outcome between stable and unstable DDH treated with a Tübingen splint. Methods: Epidemiological data and ultrasonographic data of all infants diagnosed with DDH and initially treated with a Tübingen splint at our institution between May 2017 and February 2020 were assessed retrospectively. We divided the population into stable and unstable hips using the Graf classification. Age at treatment initiation, duration of treatment, complications, and radiological outcome between 12 and 24 months were investigated. Results: We included a total of 45 patients (57 hips) affected by DDH treated with the Tübingen splint. Treatment has been successful in 93% of stable hips and only 40% of unstable hips. Radiological outcome at 1-year follow-up significantly correlated with initial Graf classification (p < 0.001). Conclusion: The Tübingen splint is a safe and effective treatment for stable hips, nevertheless, for unstable hips, closed reduction, and spica cast remains the gold standard.

Pediatric phalanx fractures: A retrospective study and review of the literature.

Purpose: Conventional radiography is frequently performed in pediatric patients in whom finger fractures are suspected. However, until now, the rate of positive findings of finger radiographic examinations in pediatric patients is unknown. This study aimed to evaluate the number of positive findings in the standard radiographic examinations of finger injuries in pediatric patients in a Level 1 trauma center systematically. Methods: We conducted a retrospective study on all children 0-16 years old admitted for acute finger injury in the Emergency Department of a University Hospital during the first semester of 2019 and received a radiographic examination. Their demographic characteristics, fracture pattern, and treatment were then analyzed and interpreted. Results: Out of 478 finger injuries reviewed in this cohort, 160 X-rays revealed positive for a fracture giving a fracture rate of 33.5%. More than half of them (51.9%) occurred in the age group of adolescents (11-16 years). Among all finger fractures, only 3.8% of them treated surgically. Conclusion: In this study, a relevant amount of standard finger radiographs revealed a low fracture rate and a rare operative indication of 3.8%. Therefore, indications for X-rays should be reviewed properly and alternative procedures should be discussed. Clinical decision rules should be developed and the necessary pathways must be implemented to minimize radiation exposure, waiting time, and costs.Level of evidence: level IV.

Kingella kingae Spinal Infections in Children.

Nowadays, Kingella kingae is considered an important cause of primary spinal infections in children aged between 6 and 48 months. The presentation of the disease is often characterized by mild clinical features and a moderate biological inflammatory response, requiring a high index of suspicion. Performing magnetic resonance imaging (MRI) and obtaining an oropharyngeal specimen and subjecting it to a K. kingae-specific nucleic acid amplification test are recommended for its diagnosis. Most patients respond promptly to conservative treatment after administration of antibiotic therapy, which is prolonged for up to 3 months according to the individual clinical and biological response. Invasive surgical procedures are not required except for children who do not improve with antibiotic treatment, develop signs of cord compression, or if the presence of atypical microorganisms is suspected. Kingella kingae spinal infections usually run an indolent and benign clinical course, living no permanent sequelae.

A Single Retrograde Intramedullary Nail Technique for Treatment of Displaced Proximal Humeral Fractures in Children: Case Series and Review of the Literature.

Displaced proximal humeral fractures in older children with low remodeling potential need to be reduced and fixed. There are many options for stabilization, including external fixation, rigid internal fixation with screws and plates, percutaneous pinning, and flexible intramedullary nailing. The use of 2 flexible retrograde nails, originated at the University of Nancy, France, became the most popular technique in Europe. The aim of this study was to describe and assess a modified, single retrograde nail technique to treat fractures of the proximal part of the humerus. METHODS: We performed a retrospective monocentric study. From June 2016 to May 2019, a modified retrograde nail technique with 1 prebent nail was used for the management of 21 consecutive children with a closed displaced proximal humeral fracture. Demographic and surgical data were collected. The surgical technique is similar to the classic elastic stable intramedullary nailing, but only 1 nail is used. The average surgical time and perioperative complications were used as criteria for the feasibility of this technique. Radiographs were obtained preoperatively; at 1, 4, and 6 weeks postoperatively; and after implant removal at an average of 4.2 months postoperatively. The clinical outcomes were assessed on the basis of the shoulder range of motion documented in the medical records and by using the French edition of the QuickDASH (shortened version of the Disabilities of the Arm, Shoulder and Hand [DASH] questionnaire) evaluation scale at the time of implant removal. RESULTS: Nineteen patients with a mean age of 12.6 years and a mean follow-up of 6 months were included in the study. The mean surgical time was 49 minutes. The single intramedullary nail technique provided a satisfactory reduction of all fractures. No perioperative complication occurred. In 1 case, partial loss of reduction was observed on the first-week control radiograph. All patients had a healed fracture, no deficits, excellent results according to the QuickDASH score, a normal range of motion, and excellent strength of the shoulder joint at the time of implant removal (at a mean of 4.2 months). CONCLUSIONS: The current study confirms the feasibility and efficacy of the single retrograde intramedullary nail technique to treat displaced proximal humeral fractures in children. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A retrospective epidemiological study of paediatric femoral fractures.

BACKGROUND: Femoral fracture is a significant major trauma in children and adolescents, sometimes resulting in serious complications. This study aimed to determine the epidemiology of femoral fractures and to define associated injuries and mortality incidence in a pediatric population below 16 years old. METHODS: The medical records of all patients with a femoral fracture treated in our hospital from 1997–2016 were reviewed retrospectively. Age, gender, mechanism of the trauma, month and season of fracture occurrence, fracture type, associated injuries, and mortality data were collected. Patients were divided into four age groups and compared. RESULTS: The study included 348 children with 353 femoral fractures. The mean annual prevalence of femoral fracture during the study period was 22.7 per 100,000 children. Except for children less than 1 year old, most fractures occurred in male patients (69%), with a male-to-female ratio of 2.2:1. Road accidents were the most common mechanism at all ages. Femoral fractures were mainly due to low-energy trauma in neonates and infants, to road accidents and low-energy trauma in preschool children, to sports accidents in school-age children, and to road traffic accidents in teenagers. February was the month with the most occurrences of femoral fractures. Winter was the peak season for femoral fractures in children aged <1 year and 6–11 years (37.8% and 46.4% of fractures respectively), whereas autumn was the most common season (29.5%) for preschool children and spring (31.1%) the most common in the teenagers group. Diaphyseal fractures were the most commonly reported lesions in all four age groups, representing 72.3% of all fractures. Only 18 fractures were open (5.1%). Eighty-eight patients (25.3%) presented with associated injuries at admission, 12 presented with Waddell’s triad of injuries, and the mortality rate was calculated to be 1.1% (four cases). CONCLUSION: The circumstances of injury and the seasonality of femoral fractures differed significantly depending on the children’s ages. Moreover, the morbidity of femoral fractures in children was closely correlated with associated injuries. (Level of evidence: Level III).

Proximal Radioulnar Translocation Associated with Posterior Fracture-Dislocation of Elbow in an Adolescent Girl: A Case Report.

CASE: A 14-year-old girl sustained a posterior elbow dislocation and presented with a proximal radioulnar translocation (PRUT) and a displaced fracture of the radial head. Reduction of the elbow dislocation and the proximal radioulnar translocation were achieved by external manipulation in the operating room. The radial head was not amenable to closed reduction and remained entrapped in the anteromedial compartment of the elbow. So open reduction and internal stabilization was carried out. CONCLUSIONS: In PRUT, closed reduction should be attempted. The radial head should be preserved even if it is fully dislocated from metaphysis. Retrograde intramedullary radial nailing provides enough stability of the fracture to promote early mobilization and facilitate union.

Kingella kingae and Osteoarticular Infections.

OBJECTIVES: In this study, we aimed to contrast the bacteriologic epidemiology of osteoarticular infections (OAIs) between 2 patient groups in successive 10-year periods, before and after the extensive use of nucleic acid amplification assays in the diagnostic process. METHODS: Epidemiologic data and bacteriologic etiologies of all children presenting with OAIs on admission to our institution over 20 years (1997-2016) were assessed retrospectively. The population was divided into 2 cohorts, using the standardized use of polymerase chain reaction as the cutoff point (2007). The conventional cohort included children with OAIs mainly investigated by using classic cultures, whereas the molecular cohort referred to patients also investigated by using molecular assays. RESULTS: Kingella kingae was the most frequently isolated pathogen, responsible for 51% of OAIs, whereas other classic pathogens were responsible for 39.7% of cases in the molecular cohort. A statistically significant increase in the mean incidence of OAIs was observed, as was a decrease in the mean age at diagnosis after 2007. After 2007, the pathogen remained unidentified in 21.6% of OAIs in our pediatric population. CONCLUSIONS: Extensive use of nucleic acid amplification assays improved the detection of fastidious pathogens and has increased the observed incidence of OAI, especially in children aged between 6 and 48 months. We propose the incorporation of polymerase chain reaction assays into modern diagnostic algorithms for OAIs to better identify the bacteriologic etiology of OAIs.

The Contemporary Bacteriologic Epidemiology of Osteoarticular Infections in Children in Switzerland.

OBJECTIVES: To assess the contemporary bacteriologic epidemiology of pediatric osteoarticular infection with particular regard to children's ages, because Kingella kingae has gained increasing recognition as the predominant pathogen for osteoarticular infection in young children. STUDY DESIGN: Retrospective file review of enrolled children from 0 to 15 years of age, admitted to our institution from 2007 to 2015 for suspected osteoarticular infection (217 cases). Information on age, sex, the bone or joint infected, imaging studies, and laboratory data (including bacterial investigations) were collected for analysis. RESULTS: Microorganism identification was possible for 138 infected children (63.6%), through blood (cultures or polymerase chain reaction [PCR]) and/or operative samples (cultures or PCR). Thirty-one patients (14.3%) were found to both have positive blood cultures and operative samples. The results of positive bacteriology specimens identified the most common causative pathogen for osteoarticular infection as K kingae (47.8% of microbiologically confirmed osteoarticular infections of all ages, and 87.7% in children between the ages of 6 and 48 months), significantly more common than Staphylococcus aureus (35.5% of microbiologically confirmed osteoarticular infections of all ages, and 78.2% in children >4 years of age). CONCLUSIONS: Use of the appropriate PCR assays demonstrated that K kingae currently is the major bacterial cause of pediatric osteoarticular infection, especially in children <4 years of age in whom K kingae is more common than S aureus. PCR assays should be used in routine microbiologic laboratory evaluation to improve diagnostic performance. However, despite the use of molecular methods, there are many osteoarticular infections in which no microorganism is detected, which suggests that these infections may be caused by other as yet unrecognized fastidious microorganisms.

Association between oropharyngeal carriage of Kingella kingae and osteoarticular infection in young children: a case-control study.

BACKGROUND: Kingella kingae has been increasingly identified in patients with osteoarticular infections. Our main objective was to evaluate the association between carriage of K. kingae in the oropharynx of preschool children and osteoarticular infections. METHODS: We conducted this prospective case-control study in 2 tertiary care pediatric hospitals (Canada and Switzerland) between 2014 and 2016. Potential cases were children aged 6 to 48 months with a presumptive diagnosis of osteoarticular infection according to the treating emergency physician. Confirmed cases were those with diagnosis of osteomyelitis or septic arthritis proven by positive findings on technetium-labelled bone scan or magnetic resonance imaging or identification of a microorganism in joint aspirate or blood. For each case, we recruited 4 age-matched controls from among children presenting to the same emergency department for trauma. The independent variable was presence of oropharyngeal K. kingae DNA identified by a specific polymerase chain reaction assay. We determined the association between oropharyngeal carriage of K. kingae and definitive osteoarticular infection. RESULTS: The parents of 77 children admitted for suspected osteoarticular infection and 286 controls were invited to participate and provided informed consent. We identified K. kingae in the oropharynx of 46 (71%) of 65 confirmed cases and 17 (6%) of 286 controls; these results yielded an odds ratio of 38.3 (95% confidence interval 18.5-79.1). INTERPRETATION: Detection of oropharyngeal K. kingae was strongly associated with osteoarticular infection among children presenting with symptoms suggestive of such infection.

[Corrective surgery for lower limb length discrepancy and malalignment in paediatric orthopaedics]. / Corrections d'axes et allongements des membres inférieurs en orthopédie pédiatrique.

Lower limb length discrepancy and malalignment in paediatric orthopaedics constitute a set of acquired or malformative structural pathologies. These anomalies, which may alter statics of lower limbs, are susceptible to engender an asymmetry of mechanical constraints' distribution across joints, and thus to promote the onset of arthritic phenomenons. The purpose of this review's article is to define the limits of tolerance of the various malformations and describe the innovative techniques available in order to correct them.

Les inégalités de longueur et les troubles d'axe des membres inférieurs constituent un ensemble de pathologies structurelles acquises ou malformatives. Ces anomalies, qui altèrent la statique des membres inférieurs, vont engendrer une asymétrie de répartition des contraintes mécaniques sur les différentes pièces osseuses et sur les articulations et, de ce fait, faciliter la survenue de phénomènes dégénératifs arthrosiques. Le but de cet article de synthèse est de définir les limites de tolérance des différentes malformations et de décrire les différentes techniques novatrices pour les corriger.

Pyogenic Tenosynovitis in Infants: A Case Series.

Pyogenic tenosynovitis is an uncommon condition in children, and there are few published case reports. We present a series of 11 cases who were treated in the Geneva Children Hospital in the last 10 years. Kingella kingae was the main pathogen, and the characteristics of infection (inflammatory indices, clinical findings and severity) are similar to other osteoarticular K. kingae infections in infants.

Pediatric Sacroiliitis: Clinical and Microbiologic Differences Between Infants and Children-Adolescents.

BACKGROUND: The aim of this study was to improve knowledge of pediatric pyogenic sacroiliitis (PSI) in the pediatric population based on a consecutive case series. METHOD: We conducted a single-center cross-sectional study on 16 patients admitted to the emergency department of our Hospital between January 1990 and December 2015 with a confirmed diagnosis of PSI. The patients were divided into 2 groups by age: infants (6 months to 4 years) and children-adolescents (4-16 years). The features of PSI, clinical signs and symptoms, laboratory tests, bacteriologic investigations, radiologic examinations and outcome were compared among the 2 groups. RESULTS: Patients in the children-adolescent group usually presented with a history of limping and buttock or lower back pain, and methicillin-susceptible Staphylococcus aureus was the most frequent pathogen. We observed a second peak of incidence of PSI in infants with consistent difference in clinical and microbiologic presentation. Infants were more likely to have an ambiguous onset with the refusal to bear weight as the only consistent clinical manifestations, and biologic investigations demonstrated higher erythrocyte sedimentation rate and platelet counts. However, all blood and joint fluid cultures were sterile in the infant group. CONCLUSION: PSI in infants and adolescents may represent 2 different conditions. Although PSI is mainly caused by S. aureus in the children-adolescent group, clinical manifestations and biologic characteristics of PSI in infants suggest Kingella kingae as the etiology osteoarticular infection. Thus, oropharyngeal swab polymerase chain reaction assay for K. kingae and magnetic resonance imaging should be considered for early diagnosis and treatment of this condition in the younger age group.

From prevention of pin-tract infection to treatment of osteomyelitis during paediatric external fixation.

Pin-tract infection (PTI) is the most commonly expected problem, or even an almost inevitable complication, when using external fixation. Left unteated, PTI will progress unavoidably, lead to mechanical pin loosening, and ultimately cause instability of the external fixator pin-bone construct. Thus, PTI remains a clinical challenge, specifically in cases of limb lengthening or deformity correction. Standardised pin site protocols which encompass an understanding of external fixator biomechanics and meticulous surgical technique during pin and wire insertion, postoperative pin site care and pin removal could limit the incidence of major infections and treatment failures. Here we discuss concepts regarding the epidemiology, physiopathology and microbiology of PTI in paediatric populations, as well as the clinical presentations, diagnosis, classification and treatment of these infections.

Primary subacute hematogenous osteomyelitis in children: a clearer bacteriological etiology.

BACKGROUND: This study aimed to describe the spectrum of pediatric primary subacute hematogenous osteomyelitis (PSAHO) and to investigate its bacterial etiology. METHODS: Sixty-five consecutive cases of PSAHO admitted to our institution over a 16-year period (2000-2015) were retrospectively reviewed to assess their laboratory and radiographic imaging features, as well as their bacteriological etiology. RESULTS: On evaluation, white blood cell count and C-reactive protein were normal in 53 (81.5 %) and 34 cases (52.3 %), respectively, whereas the erythrocyte sedimentation rate was superior to 20 mm/h in 44 cases (72.1 %). Blood cultures failed to identify the pathogen in all but one patient, and classic bone sample cultures only managed to isolate the pathogen in five cases (11.6 %). Use of polymerase chain reaction (PCR) assays on bone aspirates or blood allowed the causative microorganism to be isolated in a further 22 cases. Using classic cultures and PCR assays together resulted in pathogen detection in 27 cases (62.8 % of the children bacteriologically investigated), with Kingella kingae being the most frequently reported microorganism. CONCLUSIONS: Two distinct forms of PSAHO should be distinguished on the basis of age of patients and bacteriological etiology. The infantile form affects children aged between 6 months and 4 years and is predominantly due to K. kingae. The juvenile form involves children aged >4 years and Staphylococcus aureus appears to be the main bacteriological etiology. Appropriate nucleic amplification assays drastically improve the detection rate of the microorganisms responsible for PSAHO. LEVEL OF EVIDENCE: Case series, level IV.