Polyomavirus Wakes Up and Chooses Neurovirulence.

JC polyomavirus (JCPyV) is a human-specific polyomavirus that establishes a silent lifelong infection in multiple peripheral organs, predominantly those of the urinary tract, of immunocompetent individuals. In immunocompromised settings, however, JCPyV can infiltrate the central nervous system (CNS), where it causes several encephalopathies of high morbidity and mortality. JCPyV-induced progressive multifocal leukoencephalopathy (PML), a devastating demyelinating brain disease, was an AIDS-defining illness before antiretroviral therapy that has "reemerged" as a complication of immunomodulating and chemotherapeutic agents.

Lysophosphatidic acid signaling via LPA : A negative modulator of developmental oligodendrocyte maturation.

The developmental process of central nervous system (CNS) myelin sheath formation is characterized by well-coordinated cellular activities ultimately ensuring rapid and synchronized neural communication. During this process, myelinating CNS cells, namely oligodendrocytes (OLGs), undergo distinct steps of differentiation, whereby the progression of earlier maturation stages of OLGs represents a critical step toward the timely establishment of myelinated axonal circuits. Given the complexity of functional integration, it is not surprising that OLG maturation is controlled by a yet fully to be defined set of both negative and positive modulators.

Epiphysiodesis for Leg Length Discrepancy: A Cost Analysis of Drill Versus Screw Technique.

Research has demonstrated similar efficacy of drill epiphysiodesis and percutaneous epiphysiodesis using transphyseal screws for the management of adolescent leg length discrepancy. A cost analysis was performed to determine which procedure is more cost-effective. Patients seen for epiphysiodesis of the distal femur and/or proximal tibia and fibula between 2004 and 2017 were reviewed.

Prospective Evaluation of Tarsal Coalition Excision Show Significant Improvements in Pain and Function.

Background: Excision of pediatric tarsal coalition has been successful in most patients. However, some patients have ongoing pain after coalition excision. This study prospectively assessed patient-based clinical outcomes before and after surgical excision of tarsal coalition, with particular emphasis on comparison to radiologic imaging.

Surgical Treatment of Solitary Periarticular Osteochondromas About the Knee in Pediatric and Adolescent Patients: Complications and Functional Outcomes.

Background: Solitary osteochondromas, or osteocartilaginous exostoses (OCEs), represent the most common benign bone tumor. Despite frequently causing symptoms about the knee in younger populations, there is minimal previous literature investigating surgical treatment.

Methods: We retrospectively reviewed the records of patients <20 years old who had undergone surgical treatment of symptomatic, pathologically confirmed, solitary periarticular knee OCE at a single pediatric center between 2003 and 2016.

Best practice guidelines in managing the craniofacial aspects of skeletal dysplasia.

Background: Recognition and appropriate management of the craniofacial manifestations of patients with skeletal dysplasia are challenging, due to the rarity of these conditions, and dearth of literature to support evidence-based clinical decision making.

Methods: Using the Delphi method, an international, multi-disciplinary group of individuals, with significant experience in the care of patients with skeletal dysplasia, convened to develop multi-disciplinary, best practice guidelines in the management of craniofacial aspects of these patients.

Results: After a comprehensive literature review, 23 initial statements were generated and critically discussed, with subsequent development of a list of 22 best practice guidelines after a second round voting.

The MITF paralog tfec is required in neural crest development for fate specification of the iridophore lineage from a multipotent pigment cell progenitor.

Understanding how fate specification of distinct cell-types from multipotent progenitors occurs is a fundamental question in embryology. Neural crest stem cells (NCSCs) generate extraordinarily diverse derivatives, including multiple neural, skeletogenic and pigment cell fates. Key transcription factors and extracellular signals specifying NCSC lineages remain to be identified, and we have only a little idea of how and when they function together to control fate.

Classification of lower extremity venous malformations and risk of knee involvement: A retrospective cohort study.

Background: Venous malformation (VM) is the most common vascular anomaly in the lower extremity. VMs can be classified as focal, multifocal, or diffuse types. Intraarticular VM (IA-VM) of the knee portends morbidity.

Orthopedic issues in vascular anomalies.

Vascular anomalies impact the musculoskeletal system dependent on the tissue involved (skin, subcutis, muscle, cartilage, or bone), the extent of involvement, and the type of anomalous vessels (arteries, capillaries, veins, or lymphatics). These malformations can cause a multitude of musculoskeletal problems for the patient. Leg-length discrepancy, intra-articular involvement, muscular lesions, and primary or secondary scoliosis are amongst the issues that patients face.

Best practice guidelines for management of spinal disorders in skeletal dysplasia.

Background: Disorders of the spine present a common and difficult management concern in patients with skeletal dysplasia. Due to the rarity of these conditions however, the literature, largely consisting of small, single institution case series, is sparse in regard to well-designed studies to support clinical decision making in these situations.

Methods: Using the Delphi method, an international, multi-disciplinary group of individuals, with significant experience in the care of patients with skeletal dysplasia, convened to develop multi-disciplinary, "best practice" guidelines in the care of spinal disorders in patients with skeletal dysplasia.

Mitf-family transcription factor function is required within cranial neural crest cells to promote choroid fissure closure.

A crucial step in eye development is the closure of the choroid fissure (CF), a transient structure in the ventral optic cup through which vasculature enters the eye and ganglion cell axons exit. Although many factors have been identified that function during CF closure, the molecular and cellular mechanisms mediating this process remain poorly understood. Failure of CF closure results in colobomas.

Sodium-Calcium Exchangers of the SLC8 Family in Oligodendrocytes: Functional Properties in Health and Disease.

The solute carrier 8 (SLC8) family of sodium-calcium exchangers (NCXs) functions as an essential regulatory system that couples opposite fluxes of sodium and calcium ions across plasmalemmal membranes. NCXs, thereby, play key roles in maintaining an ion homeostasis that preserves cellular integrity. Hence, alterations in NCX expression and regulation have been found to lead to ionic imbalances that are often associated with intracellular calcium overload and cell death.

Fibroadipose Vascular Anomaly in the Upper Extremity: A Distinct Entity With Characteristic Clinical, Radiological, and Histopathological Findings.

Purpose: Fibroadipose vascular anomaly (FAVA) is an intramuscular vascular malformation that has been recently described as a distinct clinical entity. The clinical, radiological, and histopathological characteristics of FAVA in the upper extremity are reviewed.

Methods: This was a retrospective case series of upper-extremity FAVA lesions.

Surgical Management of Fibroadipose Vascular Anomaly of the Lower Extremities.

Background: Fibroadipose vascular anomaly (FAVA) is a recently-defined vascular malformation often involving the extremities and presenting in childhood. Patients may present to orthopaedic surgeons with pain, swelling, joint contractures, and leg length discrepancy. There is no established therapy or treatment paradigm.

Pulmonary thromboembolic events in patients with congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and spinal/skeletal abnormalities and Klippel-Trénaunay syndrome.

Objective: Patients with Klippel-Trénaunay syndrome (KTS) and congenital lipomatous overgrowth, vascular malformations, epidermal nevi, and spinal/skeletal abnormalities (CLOVES) syndrome have central phlebectasia and enlarged persistent embryonic veins that are often incompetent and prone to thromboembolism. The purpose of the study was to determine the presence of phlebectasia and the incidence of symptomatic pulmonary embolism (PE).

Methods: A retrospective review was conducted of patients referred to the Vascular Anomalies Center at our institution during a 21-year period who were diagnosed with KTS and CLOVES syndrome.

Preoperative Embolization of Venous Malformations Using n-Butyl Cyanoacrylate.

Purpose: The purpose of this study was to evaluate the safety and efficacy of preoperative percutaneous n-butyl cyanoacrylate (nBCA) embolization of venous malformations in children.

Material And Methods: Clinical data were retrospectively reviewed in children who underwent embolization using nBCA followed by resection of venous malformations.

Results: A total of 17 embolizations were performed in 14 patients (9 females, mean age: 5.

Subtalar Coalitions: Does the Morphology of the Subtalar Joint Involvement Influence Outcomes After Coalition Excision?

Posteromedial subtalar (PMST) coalitions are a recently described anatomic subtype of tarsal coalitions. We compared with clinical patient-based outcomes of patients with PMST and standard middle facet (MF) coalitions who had undergone surgical excision of their coalition. The included patients had undergone surgical excision of a subtalar tarsal coalition, preoperative computed tomography (CT), and patient-based outcomes measures after surgery (including the American Orthopaedic Foot and Ankle Society [AOFAS] scale and University of California, Los Angeles [UCLA], activity score).

Musculoskeletal Conditions in a Pediatric Population with Ehlers-Danlos Syndrome.

Objective: To describe musculoskeletal conditions in children with Ehlers-Danlos syndrome (EDS).

Study Design: A retrospective medical record review was performed, which evaluated 205 patients with EDS (ages 6-19 years) seen in sports medicine or orthopedic clinic at a large pediatric hospital over a 5-year period.

Results: Female (n = 147) and male (n = 57) patients were identified (mean age 12.

Treatment outcomes after insufficiency femoral diaphyseal fractures in nonambulatory children.

Unlabelled: We retrospectively reviewed the treatment and outcomes of diaphyseal femur fractures in a cohort of nonambulatory children. There were 30 patients (38 fractures) reviewed [average age of 10.1 years (range: 1.

Treatment dilemma in multiple metatarsal fractures: when to operate?

Unlabelled: Fractures of multiple metatarsals in the pediatric population are uncommon; however, indications for surgical treatment have not been delineated. The aim of this study was to review multiple metatarsal fractures to help refine surgical indications. A total of 98 patients had multiple metatarsal fractures; displacement greater than 10% shaft width (displaced) was encountered in 33 (34.

Cryoablation in fibro-adipose vascular anomaly (FAVA): a minimally invasive treatment option.

Background: Fibro-adipose vascular anomaly (FAVA) is a complex vascular malformation that typically presents with persistent pain, discomfort, contracture and other disabling symptoms. There are no minimally invasive treatment options to effectively control these symptoms. Image-guided percutaneous cryoablation, which has been used to control pain in people with cancer, could be used for similar indications in FAVA.

Best practices in the evaluation and treatment of foramen magnum stenosis in achondroplasia during infancy.

Achondroplasia is the most common inherited disorder of bone growth (skeletal dysplasia). Despite this fact, consistent and evidence-based management approaches to recognized, life-threatening complications, such as foramen magnum stenosis, are lacking. This study aims to outline best practice, based on evidence and expert consensus, regarding the diagnosis, assessment, and management of foramen magnum stenosis in achondroplasia during infancy.

Lymphatic and other vascular malformative/overgrowth disorders are caused by somatic mutations in PIK3CA.

Objectives: To test the hypothesis that somatic phosphatidylinositol-4,5-bisphospate 3-kinase, catalytic subunit alpha (PIK3CA) mutations would be found in patients with more common disorders including isolated lymphatic malformation (LM) and Klippel-Trenaunay syndrome (KTS).

Study Design: We used next generation sequencing, droplet digital polymerase chain reaction, and single molecule molecular inversion probes to search for somatic PIK3CA mutations in affected tissue from patients seen at Boston Children's Hospital who had an isolated LM (n = 17), KTS (n = 21), fibro-adipose vascular anomaly (n = 8), or congenital lipomatous overgrowth with vascular, epidermal, and skeletal anomalies syndrome (n = 33), the disorder for which we first identified somatic PIK3CA mutations. We also screened 5 of the more common PIK3CA mutations in a second cohort of patients with LM (n = 31) from Seattle Children's Hospital.

Patient-reported Outcomes of Tarsal Coalitions Treated With Surgical Excision.

Purpose: There are little patient-reported data on functional outcomes of tarsal coalition resection in children and adolescents. The purpose of this study is to evaluate the medium-term (>2 y) outcomes in patients who have had surgical excision of their symptomatic tarsal coalition and to compare patient-based outcomes in patients who have calcaneonavicular (CN) coalitions to those with talocalcaneal (TC) coalitions.

Methods: A billing query was conducted to identify patients who had surgical excision of their tarsal coalition between 2003 and 2008.