Cranio-cervical junction malformation causing cord compression in infant with achondroplasia: a bigger picture.

INTRODUCTION: Achondroplasia is a genetic disorder known for short stature and skeletal abnormalities. CASE REPORT: We present a case of narrowing of the foramen magnum from a large opisthion extending to the spinal canal. CONCLUSION: Foramen magnum stenosis and cervicomedullary stenosis are potentially life threatening neurological manifestations of achondroplasia.

Neurosurgical Evaluation and Management of Adults with Achondroplasia.

Much of the current medical discussion for within centers for skeletal dysplasia and specifically patients with achondroplasia focuses on infancy and early childhood. Most neurosurgical concerns arise due to a defect in the endochondral ossification, resulting on early fusion of the synchondrosis. As patients age, the neurosurgical focus shifts from primarily cranial to spinal concerns. Often pediatric neurosurgeons may continue to follow their patients with skeletal dysplasia. However, general adult neurosurgeons and orthopedic surgeons may see these graduated adults in their practice. This article provides a review of the common neurosurgical concerns for patients with achondroplasia.

Neurosurgical Evaluation and Management of Children with Achondroplasia.

Achondroplasia is the most common of skeletal dysplasias and is caused by a defect in endochondral bone formation. In addition to skeletal deformities, patients with achondroplasia possess significant abnormalities of the axial skeleton, including small skull base with a narrowed foramen magnum and small vertebral bodies with shortened pedicles. Consequently, patients with achondroplasia are at risk of several severe neurologic conditions, such as cervicomedullary compression, spinal stenosis, and hydrocephalus, which frequently require the attention of a neurosurgeon. This article provides an updated review on the neurosurgical evaluation and care of children with Achondroplasia.

Morquio Syndrome Presenting with Dural Band Pathology: A Case Report.

Morquio syndrome is caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS) enzyme, which is required for the catabolism of glycosaminoglycans (namely, chondroitin-6-sulfate and keratan sulfate). Pathogenic accumulation of these glycosaminoglycans occurs throughout the body. The various organs and tissues affected are bones, cartilage, tendon, teeth, trachea and lungs, heart, cornea, skin and connective tissues. Here, we present a case of Morquio syndrome. A 16-year-old boy presented with multiple skeletal abnormalities, including cervicomedullary compression by dorsal dural band in foramen magnum. The dural band was resected during the surgery to relieve compression and sent for histopathological examination. This case report not only reviews the clinical features and shows rare dural band histopathological findings but also mentions a note on the future therapies of this syndrome.

Polysomnography as an indicator for cervicomedullary decompression to treat foramen magnum stenosis in achondroplasia.

OBJECTIVE: Management of cervicomedullary compression due to foramen magnum stenosis in achondroplasia remains controversial, especially for patients with no symptoms or mild symptoms. We examined the effectiveness of polysomnography (PSG) as an indicator for cervicomedullary decompression treatment. METHODS: We retrospectively reviewed nine achondroplasia cases (mean age 1 year and 9 months) treated from 2008 to 2015. All patients were examined by PSG, magnetic resonance imaging (MRI), and otolaryngeal fibroscopy. We analyzed demographic data, clinical presentation, degree and type of respiratory impairment, severity of foramen magnum stenosis and concomitant cervicomedullary compression, treatment (conservative or surgical), and clinical outcome. RESULTS: Eight of nine patients presented with no severe symptoms in the daytime. However, MRI revealed four severe, four moderate, and one mild case of cervicomedullary compression, and PSG demonstrated severe sleep apnea in four cases and moderate sleep apnea in five cases. All sleep apnea cases were obstructive or obstructive-dominant. Fibroscopy revealed no upper airway stenosis in six cases and mild stenosis in three cases. Four patients who had severe sleep-related respiratory disturbance on PSG and severe or moderate cervicomedullary compression were treated by cervicomedullary decompression. Three of these patients demonstrated improved sleep respiration soon after surgery, while one required temporary tracheostomy due to bilateral vocal cord paralysis caused by compression during intratracheal intubation. CONCLUSION: Polysomnography can be a useful indicator for cervicomedullary decompression surgery, especially in cases of seemingly asymptomatic achondroplasia with severe foramen magnum stenosis.

Endoscopic approaches to the craniovertebral junction and odontoid process.

BACKGROUND: The microsurgical transoral approach has traditionally been the preferred access for ventral decompression of the craniovertebral junction. This natural corridor, although direct, may be a challenging approach because of potential morbidities. The evolution of endoscopic methods in skull base surgeries has reduced morbidity and improved results. Endoscopic approaches are also being used for ventral decompression at the craniovertebral junction. Some technical modifications in this approach are described. METHODS: An endoscope is inserted endonasally for a panoramic view of the entire area of interest, from the sphenoid to second cervical vertebra. Image guidance systems are used in all cases to guide the resection. The soft palate is retracted away with a rubber catheter sling when both nasal and oral corridors are being used. Various mucosal flaps are raised for access and reconstruction. Actual decompression can be done through the nasal or oral corridors based on the relationship of the pathology to the palate. Reconstruction is done using standard principles with the vascularized flaps, fat, and fibrin glue. RESULTS: Reduced surgical morbidity by avoiding palatal split and good postoperative healing are some of the advantages of this modified endoscopic technique. Better surgical exposure and a wide perspective facilitate the decompression. However, as with all newer perspectives, a learning curve exists. CONCLUSIONS: Used judiciously, this modified endoscopic approach to the craniovertebral junction and odontoid process is minimally invasive and adds to the surgeon's armamentarium.

Acondroplasia -estenosis del canal medular- una complicación neurológica / Achondroplasia -spinal canal stenosis-a neurological complication

Introducción. La acondroplasia es un trastorno genético del crecimiento óseo de herencia autosómica dominante. Su incidencia es de 1:26,000 nacimientos por año. Este trastorno es causado por una mutación en el gen que codifica al receptor tipo 3 del factor de crecimiento del fibroblasto (FGFR3) en el cromosoma 4, el cual se expresa en los condrocitos de la placa de crecimiento de los huesos; de esta manera afecta la osificación endocondral. Se manifiesta clínicamente por talla baja con desproporción anatómica, macrocefalia, acortamiento de extremidades y deformidades esqueléticas. Las complicaciones neurológicas de la acondroplasia son la causa más frecuente de morbilidad y mortalidad. Caso clínico. Se trata de un paciente femenino de 5 años de edad con acondroplasia que ingresó con diagnóstico de enfermedad tipo influenza. A la exploración física presentaba clonus, hiperreflexia, limitación funcional de extremidades y retraso del desarrollo psicomotor. Durante su estancia intrahospitalaria presentó paro respiratorio que ameritó fase III de ventilación; por la debilidad de los músculos torácicos no fue posible la extubación. Se realizó una tomografía de cráneo y una imagen de resonancia magnética cráneo-cervical, encontrando la compresión del canal cérvico-medular. Conclusiones. La identificación temprana de la compresión medular y su descompresión inmediata pueden ayudar a prevenir complicaciones serias, como la insuficiencia respiratoria y la muerte súbita.

Background. Achondroplasia (AC) is an autosomal dominant genetic disorder of bone growth with an annual incidence of 1:26,000 births. It is caused by a mutation in the gene encoding the receptor type 3 growth of fibroblast factor (FGFR3) on chromosome 4, which is present in chondrocytes of the growth plate of bones, thus affecting endochondral ossification. It is manifested clinically by short stature with anatomic disproportion, macrocephaly, shortened limbs and skeletal deformities. Neurological complications of AC are the most common cause of morbidity and mortality. Case report. We report the case of a 5-year-old female patient with achondroplasia who was admitted with a diagnosis of influenza-like illness. Physical examination revealed clonus, hyperreflexia, limb functional limitation, and delayed psychomotor development. During her hospital stay the patient experienced respiratory arrest, necessitating the use of phase III mechanical ventilation, making extubation impossible due to weakness of chest muscles. Cranial computed tomography (CT) and cervical magnetic resonance imaging (MRI) were performed, demonstrating compression of the cervicospinal canal. Conclusions. Early identification of spinal cord compression and its immediate decompression can help to prevent serious complications, including respiratory failure and sudden death.