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Occipital-cervical instability in Morquio disease: A presentation of two cases and a review of the literature
Inestabilidad occipitocervical en la enfermedad de Morquio. Presentación de 2 casos y revisión de la literatura
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Ruiz-Picazo, M.A. Díez-Ulloa" "autores" => array:2 [ 0 => array:3 [ "nombre" => "D." "apellidos" => "Ruiz-Picazo" "referencia" => array:1 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">a</span>" "identificador" => "aff0005" ] ] ] 1 => array:4 [ "nombre" => "M.A." "apellidos" => "Díez-Ulloa" "email" => array:1 [ 0 => "maximoalberto.diez@usc.es" ] "referencia" => array:2 [ 0 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">b</span>" "identificador" => "aff0010" ] 1 => array:2 [ "etiqueta" => "<span class="elsevierStyleSup">*</span>" "identificador" => "cor0005" ] ] ] ] "afiliaciones" => array:2 [ 0 => array:3 [ "entidad" => "Servicio de Cirugía Ortopédica y Traumatología, Complejo Hospitalario Universitario de Albacete, Albacete, Spain" "etiqueta" => "a" "identificador" => "aff0005" ] 1 => array:3 [ "entidad" => "Unidad de Raquis, Servicio de Cirugía Ortopédica y Traumatología, Complejo Hospitalario Universitario de Santiago de Compostela, Santiago de Compostela, A Coruña, Spain" "etiqueta" => "b" "identificador" => "aff0010" ] ] "correspondencia" => array:1 [ 0 => array:3 [ "identificador" => "cor0005" "etiqueta" => "⁎" "correspondencia" => "Corresponding author." ] ] ] ] "titulosAlternativos" => array:1 [ "es" => array:1 [ "titulo" => "Inestabilidad occipitocervical en la enfermedad de Morquio. Presentación de 2 casos y revisión de la literatura" ] ] "resumenGrafico" => array:2 [ "original" => 0 "multimedia" => array:7 [ "identificador" => "fig0010" "etiqueta" => "Figure 2" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr2.jpeg" "Alto" => 613 "Ancho" => 1400 "Tamanyo" => 171601 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0060" class="elsevierStyleSimplePara elsevierViewall">Spinal compression in an MRI scan. PADI of 5.1<span class="elsevierStyleHsp" style=""></span>mm.</p>" ] ] ] "textoCompleto" => "<span class="elsevierStyleSections"><span id="sec0005" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0075">Introduction</span><p id="par0005" class="elsevierStylePara elsevierViewall">Mucopolysaccharidoses (MPS) are a family of hereditary diseases involving deposits of lysosomes resulting from an enzyme deficit in the metabolism of glycosaminoglycans (GAG). There are six forms of MPS, each presenting a different phenotypic grade.</p><p id="par0010" class="elsevierStylePara elsevierViewall">Morquio disease (MPS IVA) is an autosomal recessive deficit in the activity of certain enzymes, N-acetylgalactosamine-6-sulfatase (MPS IVA) or β-galactosidase (MPS IVB), resulting in the accumulation of keratan sulfate and chondroitin-6-sulfate.<a class="elsevierStyleCrossRef" href="#bib0005"><span class="elsevierStyleSup">1</span></a> Skeletal manifestations in spondyloepiphyseal dysplasia include a delay in growth, odontoid hypoplasia, thoracolumbar kyphosis, hip dysplasia, <span class="elsevierStyleItalic">genu valgo</span>, liver spots and joint laxity, with normal mental capacity. The estimated incidence oscillates between 1/76,000 (Northern Ireland) and 1/640,000 (Western Australia) live births.<a class="elsevierStyleCrossRef" href="#bib0010"><span class="elsevierStyleSup">2</span></a> Life expectancy is variable, depending on the degree of severity of the disease, but many patients die in adult age, approximately in the third decade of life, due to cardiopulmonary diseases or sequelae from neurological deficits.</p><p id="par0015" class="elsevierStylePara elsevierViewall">The natural progression of this disease can lead to quadriplegia and sudden death secondary to atlantoaxial instability and spinal compression. Children with MPS IVA suffer odontoid hypoplasia, joint laxity and extradural deposits of GAG anterior to the spine at the C1 level which can result in atlantoaxial subluxation, stenosis and cervical myelopathy. GAG deposits are not observed in radiographs, they can only be detected by magnetic resonance imaging (MRI) which means that occipitocervical stenosis could be more severe than suspected from radiographs.<a class="elsevierStyleCrossRefs" href="#bib0005"><span class="elsevierStyleSup">1,3,4</span></a> Compression caused by the deposits, added to instability, can result in progressive weakness with myelopathy, thus leading some authors to favor occipitocervical fixation once instability has been demonstrated.<a class="elsevierStyleCrossRefs" href="#bib0005"><span class="elsevierStyleSup">1,3–7</span></a></p></span><span id="sec0010" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0080">Physiopathology of atlantoaxial instability in Morquio syndrome</span><p id="par0020" class="elsevierStylePara elsevierViewall">The joint located between the anterior arch of C1 and the odontoid enables 50% of cervical lateral rotation. The correct function of the transverse and alar ligaments maintains the integrity of the atlantoaxial joint, limiting posterior translation of the odontoid.</p><p id="par0025" class="elsevierStylePara elsevierViewall">The distance between the anterior C1 arch and the odontoid apophysis (known as ADI), which is normally up to 2.5<span class="elsevierStyleHsp" style=""></span>mm in adults and 5<span class="elsevierStyleHsp" style=""></span>mm in children, is increased in flexion by subluxation of the segment, caused by a tendency toward local instability. This is just an indirect measurement of the space that is left for the spine, the truly important parameter, which is also measured between the posterior C1 arch and the odontoid apophysis (PADI) when there is difficulty to visualize the anterior atlantoaxial joint. In radiographs in flexion, when this displacement (dynamic concept) makes the ADI greater than the limits mentioned previously as normal, or when there is a variation greater than 2<span class="elsevierStyleHsp" style=""></span>mm between the ADI in the lateral radiograph in flexion and in extension, we refer to atlantoaxial instability.<a class="elsevierStyleCrossRef" href="#bib0010"><span class="elsevierStyleSup">2</span></a></p><p id="par0030" class="elsevierStylePara elsevierViewall">Atlantoaxial instability is a common finding in MPS IVA and is thought to derive from odontoid hypoplasia, along with associated ligament laxity.<a class="elsevierStyleCrossRefs" href="#bib0040"><span class="elsevierStyleSup">8–10</span></a> Furthermore, instability in this entity can be multidirectional, both anteroposterior and mediolateral or craniocaudal, or even an association of all these components.</p><p id="par0035" class="elsevierStylePara elsevierViewall">In flexion, the anterior C1 arch is displaced anteroinferiorly. Without competent ligaments which ensure that the odontoid follows the movement of C1, the posterior tilt of the odontoid (impingement) could cause compression of the cervical spine.</p></span><span id="sec0015" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0085">Materials and method</span><p id="par0040" class="elsevierStylePara elsevierViewall">We present two case reports treated at the hospital of the second author. The first patient was a 4-year-old boy who was referred from the Spine Unit for assessment of multiple epiphyseal dysplasia in a context of Morquio disease. The patient presented <span class="elsevierStyleItalic">pectus carinatum</span>, relative macrocephaly, severe bilateral <span class="elsevierStyleItalic">genu valgo</span>, scoliosis and thoracolumbar kyphosis. Following treatment for kyphoscoliosis with a plaster cast under general anesthesia and a TLSO-type brace, he began to present some signs of C1–C2 instability due to <span class="elsevierStyleItalic">os odontoideum</span> (<a class="elsevierStyleCrossRef" href="#fig0005">Fig. 1</a>). The radiographs showed occipitocervical instability and the MRI scan revealed spinal stenosis with a PADI of 5.5<span class="elsevierStyleHsp" style=""></span>mm (<a class="elsevierStyleCrossRef" href="#fig0010">Fig. 2</a>). In light of these clinical characteristics, occipitocervical decompression-arthrodesis was indicated at the age of 8 years (<a class="elsevierStyleCrossRefs" href="#fig0015">Figs. 3 and 4</a>). During the evolution, the patient was included in a study with enzyme replacement therapy.</p><elsevierMultimedia ident="fig0005"></elsevierMultimedia><elsevierMultimedia ident="fig0010"></elsevierMultimedia><elsevierMultimedia ident="fig0015"></elsevierMultimedia><elsevierMultimedia ident="fig0020"></elsevierMultimedia><p id="par0045" class="elsevierStylePara elsevierViewall">The second patient was an 8-year-old girl. On exploration, she pointed to numbness of hands and feet with frequent falls due to gait instability, with bilateral calf clonus of five to six shakes. Although the static radiograph was unremarkable, dynamic radiographs showed occipitocervical instability (<a class="elsevierStyleCrossRef" href="#fig0025">Fig. 5</a>). The study was completed by computed tomography (CT) and MRI (<a class="elsevierStyleCrossRef" href="#fig0030">Fig. 6</a>) scans, which confirmed stenosis at the level of the occipitocervical joint (PADI 5.7<span class="elsevierStyleHsp" style=""></span>mm) and fusion anomalies in C1 and C2 which conditioned spinal compression, leading to a proposal of occipitocervical arthrodesis to C2 (<a class="elsevierStyleCrossRef" href="#fig0035">Fig. 7</a>).</p><elsevierMultimedia ident="fig0025"></elsevierMultimedia><elsevierMultimedia ident="fig0030"></elsevierMultimedia><elsevierMultimedia ident="fig0035"></elsevierMultimedia></span><span id="sec0020" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0090">Results</span><p id="par0050" class="elsevierStylePara elsevierViewall">The first case, with a follow-up period of 6 years, is currently asymptomatic, maintaining an adequate cervical coronal and sagittal axis, with no accompanying symptoms. Furthermore, the patient was also intervened for right <span class="elsevierStyleItalic">genu valgo</span> through hemiepiphysiodesis with an 8-shaped plate.</p><p id="par0055" class="elsevierStylePara elsevierViewall">The postoperative period of the second case developed without incidents. Six months after the intervention, the symptoms improved, the patient fell less often and felt more agile, and numbness in hands and legs disappeared. After 1 year of follow-up, she is currently asymptomatic.</p></span><span id="sec0025" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0095">Discussion</span><p id="par0060" class="elsevierStylePara elsevierViewall">MPS are a group of metabolic disorders, each of them characterized by a defect of a lysosomal enzyme. These disorders result in the accumulation of different types of GAG in cells, causing central nervous system, cardiovascular, pulmonary, ophthalmological, auditory and musculoskeletal disorders. Type IV MPS (Morquio syndrome) has predominantly orthopedic manifestations, involving severe problems of the vertebral spine.</p><p id="par0065" class="elsevierStylePara elsevierViewall">Morquio syndrome was first described by Morquio<a class="elsevierStyleCrossRefs" href="#bib0055"><span class="elsevierStyleSup">11,12</span></a> and Brailsford<a class="elsevierStyleCrossRef" href="#bib0065"><span class="elsevierStyleSup">13</span></a> in 1929. This rare, hereditary disorder, transmitted in an autosomal recessive pattern, is characterized by the reduction or absence of activity of N-acetylgalactosamine-6-sulfatase in Morquio type A,<a class="elsevierStyleCrossRef" href="#bib0070"><span class="elsevierStyleSup">14</span></a> or β-galactosidase in Morquio type B.<a class="elsevierStyleCrossRef" href="#bib0075"><span class="elsevierStyleSup">15</span></a> These enzyme deficiencies lead to a lack of degradation of keratan and chondroitin sulfate, which cause the clinical characteristics of skeletal dysplasia through intracellular accumulation.</p><p id="par0070" class="elsevierStylePara elsevierViewall">In MPS IVA there is an interruption of normal development and maturation of cartilage and bone leading to multiple structural anomalies of the vertebral spine. Incomplete ossification of the odontoid causes local mechanical instability, very frequent in this syndrome. Other vertebral anomalies include platyspondylia, thoracolumbar kyphosis, specific shape of the vertebral bodies sharpened anteriorly in the sagittal plane, posterior vertebral scalloping and widened ribs.</p><p id="par0075" class="elsevierStylePara elsevierViewall">The diagnosis is established by the physical and radiographic characteristics, deficiency in enzyme activity in fibroblast cultures, excessive accumulation of keratan sulfate in urine and confirmation through enzyme analysis.<a class="elsevierStyleCrossRefs" href="#bib0005"><span class="elsevierStyleSup">1,5</span></a> Prenatal diagnosis is also possible through electrophoresis of GAG in the amniotic fluid.<a class="elsevierStyleCrossRef" href="#bib0080"><span class="elsevierStyleSup">16</span></a></p><p id="par0080" class="elsevierStylePara elsevierViewall">Regarding more specific imaging tests, 3D-CT can provide reconstructed images of the superior cervical spine for preoperative planning. Furthermore, it can be an alternative to MRI, as it is faster to perform and is able to study instability with images in flexion and extension. It is important to bear the amount of radiation in mind (specific protocols for low doses of ionizing radiation). Regarding MRI, it is the ideal method to assess the degree of spinal compression, soft tissues, and it can also provide images of the instability in flexion-extension directly. Nevertheless, being a slower test compared to CT, it sometimes requires anesthesia in order to ensure that children remain still long enough to perform the test.</p><p id="par0085" class="elsevierStylePara elsevierViewall">There is currently no data about the value of evoked potentials in the determination of spinal compression in the occipitocervical joint or in other locations in MPS IVA. Solanski et al. do not recommend testing potentials for the diagnosis or follow-up of progression of spinal compression in Morquio syndrome.<a class="elsevierStyleCrossRef" href="#bib0010"><span class="elsevierStyleSup">2</span></a></p><p id="par0090" class="elsevierStylePara elsevierViewall">MPS IVA requires a multidisciplinary approach to ensure a correct management of these patients. Close collaboration between the professionals treating these patients is essential to prevent neurological deterioration in those suffering MPS IVA.</p><p id="par0095" class="elsevierStylePara elsevierViewall">Anesthetic management of patients with MPS IVA who are candidates for surgery is very complex. The accumulation of GAG at the level of the airway can cause difficulties for intubation and ventilation. Pulmonary function can be affected by obstruction of the upper airways, restrictive pulmonary disease secondary to scoliosis/thoracic kyphosis, <span class="elsevierStyleItalic">pectus carinatum</span> and respiratory muscle weakness secondary to myelopathy by chronic spinal compression. Since these complications increase the risk of perioperative morbidity and mortality, patients with MPS IVA should be treated by anesthetists with experience in these situations.</p><p id="par0100" class="elsevierStylePara elsevierViewall">Cervical instability and the resulting stenosis are the most common causes of surgical interventions in the spine of patients with Morquio disease.<a class="elsevierStyleCrossRef" href="#bib0005"><span class="elsevierStyleSup">1</span></a> The indications for surgery include neurological involvement on instability and spinal compression with changes in the MRI signal (myelomalacia), even without symptoms. Although prophylactic fusion has been recommended to prevent cervical myelopathy with better results in neurological recovery compared to performing fixation once the stenosis has become established,<a class="elsevierStyleCrossRef" href="#bib0025"><span class="elsevierStyleSup">5</span></a> this must be assessed together with the family on a case by case basis, since it involves a considerable surgical procedure on a child with perioperative morbidity who, at the time of diagnosis, may be asymptomatic.</p><p id="par0105" class="elsevierStylePara elsevierViewall">The main objectives of this surgery are to prevent the progression of spinal damage through decompression and to correct the instability and the deformity. In the thoracolumbar spine, where the stenosis is associated to kyphosis, decompression and correction of the sagittal and coronal planes are the main objectives.</p><p id="par0110" class="elsevierStylePara elsevierViewall">When atlantoaxial subluxation advances to instability according to the previously mentioned concepts, the advice is to employ posterior cervical arthrodesis for stabilization, occasionally requiring the association of a decompression of the <span class="elsevierStyleItalic">foramen magnum</span> in order to guarantee spinal decompression.</p><p id="par0115" class="elsevierStylePara elsevierViewall">Instrumentation of the superior cervical spine has evolved considerably in recent years. The previous techniques based on cerclage (Brooks, Gallie) have become obsolete through the development of adapted occipital plates, polyaxial screws and the possibility of placing them in a transarticular position, in the lateral masses, C2 pedicle, in the pars or in a transluminal position. Placement of screws through the lamina or pedicle has been proven safer in free hand fixation of the C2 vertebra.<a class="elsevierStyleCrossRef" href="#bib0085"><span class="elsevierStyleSup">17</span></a></p><p id="par0120" class="elsevierStylePara elsevierViewall">Occasionally, surgery with fixation to C2 is not possible in very young patients or those with a severely altered anatomy.<a class="elsevierStyleCrossRef" href="#bib0090"><span class="elsevierStyleSup">18</span></a></p><p id="par0125" class="elsevierStylePara elsevierViewall">The short-term postoperative results are generally good, with high rates of arthrodesis and considerable neurological improvement. Long-term follow-up is essential to detect and treat any complications. There are very few articles showing long-term results, especially beyond 5 years. A study with a follow-up period of over 16 years observed that the most severe long-term complications were instability at the distal level of the instrumentation, conditioning longer fixations to ensure stability, as well as the possibility of appearance of new stenoses caused by kyphotic deformities at the level of the cervicothoracic or thoracolumbar junction.<a class="elsevierStyleCrossRef" href="#bib0095"><span class="elsevierStyleSup">19</span></a></p></span><span id="sec0030" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0100">Conclusion</span><p id="par0130" class="elsevierStylePara elsevierViewall">Involvement of the spine is a significant cause of disability and death in MPS IVA.</p><p id="par0135" class="elsevierStylePara elsevierViewall">It is important to correlate clinical and neurological findings with imaging studies. MRI is the most useful imaging technique to assess the degree of stenosis and spinal compression. Arthrodesis and decompression are safe and effective surgical interventions for symptomatic patients, but the long-term results are not clear. Patients showing evidence of spinal compression and/or cervical instability, even asymptomatic ones, can be considered for the intervention in order to prevent neurological lesions. Any elective procedure requires meticulous anesthetic planning based on the characteristics of each patient.</p><p id="par0140" class="elsevierStylePara elsevierViewall">Correlating the genotype and phenotype could serve to assess risk, predict results, guide treatment strategies and aid in the design of new therapies. Regarding its compassionate application, the use of recombinant human bone morphogenetic protein-2 in pediatric patients with MPS IVA has been shown to improve the rates of arthrodesis without a need for bone grafts, and leads to ossification of the odontoid.<a class="elsevierStyleCrossRef" href="#bib0010"><span class="elsevierStyleSup">2</span></a> There are currently some clinical studies focusing on enzyme replacement therapy which could lead to a treatment option in the future.</p></span><span id="sec0035" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0105">Level of evidence</span><p id="par0145" class="elsevierStylePara elsevierViewall">Level of evidence V.</p></span><span id="sec0040" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0110">Ethical responsibilities</span><span id="sec0045" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0115">Protection of people and animals</span><p id="par0150" class="elsevierStylePara elsevierViewall">The authors declare that this investigation did not require experiments on humans or animals.</p></span><span id="sec0050" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0120">Confidentiality of data</span><p id="par0155" class="elsevierStylePara elsevierViewall">The authors declare that this work does not reflect any patient data.</p></span><span id="sec0055" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0125">Right to privacy and informed consent</span><p id="par0160" class="elsevierStylePara elsevierViewall">The authors declare that this work does not reflect any patient data.</p></span></span><span id="sec0060" class="elsevierStyleSection elsevierViewall"><span class="elsevierStyleSectionTitle" id="sect0130">Conflict of interest</span><p id="par0165" class="elsevierStylePara elsevierViewall">The authors have no conflict of interest to declare.</p></span></span>" "textoCompletoSecciones" => array:1 [ "secciones" => array:14 [ 0 => array:2 [ "identificador" => "xres381334" "titulo" => array:6 [ 0 => "Abstract" 1 => "Introduction" 2 => "Objective" 3 => "Patients and methods" 4 => "Results" 5 => "Conclusion" ] ] 1 => array:2 [ "identificador" => "xpalclavsec360107" "titulo" => "Keywords" ] 2 => array:2 [ "identificador" => "xres381335" "titulo" => array:6 [ 0 => "Resumen" 1 => "Introducción" 2 => "Objetivo" 3 => "Pacientes y métodos" 4 => "Resultados" 5 => "Conclusión" ] ] 3 => array:2 [ "identificador" => "xpalclavsec360108" "titulo" => "Palabras clave" ] 4 => array:2 [ "identificador" => "sec0005" "titulo" => "Introduction" ] 5 => array:2 [ "identificador" => "sec0010" "titulo" => "Physiopathology of atlantoaxial instability in Morquio syndrome" ] 6 => array:2 [ "identificador" => "sec0015" "titulo" => "Materials and method" ] 7 => array:2 [ "identificador" => "sec0020" "titulo" => "Results" ] 8 => array:2 [ "identificador" => "sec0025" "titulo" => "Discussion" ] 9 => array:2 [ "identificador" => "sec0030" "titulo" => "Conclusion" ] 10 => array:2 [ "identificador" => "sec0035" "titulo" => "Level of evidence" ] 11 => array:3 [ "identificador" => "sec0040" "titulo" => "Ethical responsibilities" "secciones" => array:3 [ 0 => array:2 [ "identificador" => "sec0045" "titulo" => "Protection of people and animals" ] 1 => array:2 [ "identificador" => "sec0050" "titulo" => "Confidentiality of data" ] 2 => array:2 [ "identificador" => "sec0055" "titulo" => "Right to privacy and informed consent" ] ] ] 12 => array:2 [ "identificador" => "sec0060" "titulo" => "Conflict of interest" ] 13 => array:1 [ "titulo" => "References" ] ] ] "pdfFichero" => "main.pdf" "tienePdf" => true "fechaRecibido" => "2014-02-12" "fechaAceptado" => "2014-03-17" "PalabrasClave" => array:2 [ "en" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Keywords" "identificador" => "xpalclavsec360107" "palabras" => array:4 [ 0 => "Morquio syndrome" 1 => "Occipital-cervical instability" 2 => "Spinal stenosis" 3 => "Occipital-cervical arthrodesis" ] ] ] "es" => array:1 [ 0 => array:4 [ "clase" => "keyword" "titulo" => "Palabras clave" "identificador" => "xpalclavsec360108" "palabras" => array:4 [ 0 => "Síndrome de Morquio" 1 => "Inestabilidad occipitocervical" 2 => "Estenosis medular" 3 => "Artrodesis occipitocervical" ] ] ] ] "tieneResumen" => true "resumen" => array:2 [ "en" => array:2 [ "titulo" => "Abstract" "resumen" => "<span class="elsevierStyleSectionTitle" id="sect0010">Introduction</span><p id="spar0030" class="elsevierStyleSimplePara elsevierViewall">Morquio syndrome is caused by an inherited autosomal recessive enzyme deficiency. It presents with numerous musculoskeletal anomalies, among which atlantoaxial instability is highlighted, due it being life-threatening. Occipital-cervical arthrodesis surgery (and decompression) is indicated in these cases.</p> <span class="elsevierStyleSectionTitle" id="sect0015">Objective</span><p id="spar0035" class="elsevierStyleSimplePara elsevierViewall">The cases of two patients with Morquio syndrome that required this type of surgery are presented, along with a review of the literature.</p> <span class="elsevierStyleSectionTitle" id="sect0020">Patients and methods</span><p id="spar0040" class="elsevierStyleSimplePara elsevierViewall">Two patients: one boy and one girl, with Morquio syndrome and high cervical instability, with neurological signs and symptoms, who were subjected to surgery using decompression and instrumented occipital-cervical arthrodesis and followed up for 6 months and 1 year, respectively.</p> <span class="elsevierStyleSectionTitle" id="sect0025">Results</span><p id="spar0045" class="elsevierStyleSimplePara elsevierViewall">The neurological problems of both patients improved, and are currently having a normal life for their age.</p> <span class="elsevierStyleSectionTitle" id="sect0030">Conclusion</span><p id="spar0050" class="elsevierStyleSimplePara elsevierViewall">Occipital-cervical arthrodesis with decompression provides a safe biomechanical environment that prevents neurological involvement. It should be indicated before the appearance of symptoms or mechanical instability.</p>" ] "es" => array:2 [ "titulo" => "Resumen" "resumen" => "<span class="elsevierStyleSectionTitle" id="sect0040">Introducción</span><p id="spar0005" class="elsevierStyleSimplePara elsevierViewall">El síndrome de Morquio se produce por un déficit enzimático de herencia autosómica recesiva. Presenta numerosas manifestaciones musculoesqueléticas, entre las que destaca por su riesgo vital la inestabilidad atloaxoidea. En estos casos está indicada la cirugía de artrodesis (y descompresión) occipitocervical.</p> <span class="elsevierStyleSectionTitle" id="sect0045">Objetivo</span><p id="spar0010" class="elsevierStyleSimplePara elsevierViewall">Se presentan 2 pacientes con síndrome de Morquio que precisaron de este tipo de cirugía, así como una revisión de la literatura.</p> <span class="elsevierStyleSectionTitle" id="sect0050">Pacientes y métodos</span><p id="spar0015" class="elsevierStyleSimplePara elsevierViewall">Dos pacientes: un niño y una niña, con síndrome de Morquio e inestabilidad cervical alta, con signos y síntomas neurológicos, que fueron intervenidos quirúrgicamente mediante descompresión y artrodesiso occipitocervical instrumentada; con un seguimiento de 6 y un año respectivamente.</p> <span class="elsevierStyleSectionTitle" id="sect0055">Resultados</span><p id="spar0020" class="elsevierStyleSimplePara elsevierViewall">Ambos pacientes mejoraron de sus problemas neurológicos, realizando en al actualidad una vida normal para su edad.</p> <span class="elsevierStyleSectionTitle" id="sect0060">Conclusión</span><p id="spar0025" class="elsevierStyleSimplePara elsevierViewall">La artrodesis occipitocervical con descompresión proporciona un entorno biomecánico seguro que previene de la afectación neurológica. Estaría indicada ante la aparición de sintomatología o de inestabilidad mecánica.</p>" ] ] "NotaPie" => array:1 [ 0 => array:2 [ "etiqueta" => "☆" "nota" => "<p class="elsevierStyleNotepara" id="npar0005">Please cite this article as: Ruiz-Picazo D, Díez-Ulloa MA. Inestabilidad occipitocervical en la enfermedad de Morquio. Presentación de 2 casos y revisión de la literatura. Rev Esp Cir Ortop Traumatol. 2014;58:387–394.</p>" ] ] "multimedia" => array:7 [ 0 => array:7 [ "identificador" => "fig0005" "etiqueta" => "Figure 1" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr1.jpeg" "Alto" => 714 "Ancho" => 1400 "Tamanyo" => 161903 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0055" class="elsevierStyleSimplePara elsevierViewall">Dynamic radiographs in flexion and extension, showing superior cervical instability.</p>" ] ] 1 => array:7 [ "identificador" => "fig0010" "etiqueta" => "Figure 2" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr2.jpeg" "Alto" => 613 "Ancho" => 1400 "Tamanyo" => 171601 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0060" class="elsevierStyleSimplePara elsevierViewall">Spinal compression in an MRI scan. PADI of 5.1<span class="elsevierStyleHsp" style=""></span>mm.</p>" ] ] 2 => array:7 [ "identificador" => "fig0015" "etiqueta" => "Figure 3" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr3.jpeg" "Alto" => 1127 "Ancho" => 1400 "Tamanyo" => 195147 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0065" class="elsevierStyleSimplePara elsevierViewall">Postoperative radiographs after 6 years of follow-up.</p>" ] ] 3 => array:7 [ "identificador" => "fig0020" "etiqueta" => "Figure 4" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr4.jpeg" "Alto" => 547 "Ancho" => 1400 "Tamanyo" => 133394 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0070" class="elsevierStyleSimplePara elsevierViewall">Postoperative MRI scan showing an increase of the spinal canal after spinal decompression.</p>" ] ] 4 => array:7 [ "identificador" => "fig0025" "etiqueta" => "Figure 5" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr5.jpeg" "Alto" => 1783 "Ancho" => 1400 "Tamanyo" => 246830 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0075" class="elsevierStyleSimplePara elsevierViewall">Static and dynamic radiographs illustrating how occipitocervical instability goes undetected in static images.</p>" ] ] 5 => array:7 [ "identificador" => "fig0030" "etiqueta" => "Figure 6" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr6.jpeg" "Alto" => 1401 "Ancho" => 1500 "Tamanyo" => 290543 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0080" class="elsevierStyleSimplePara elsevierViewall">3D-CT reconstruction and MRI. Identification of C1 fusion anomalies, presence of <span class="elsevierStyleItalic">os odontoideum</span> and spinal compression at the occipitocervical level.</p>" ] ] 6 => array:7 [ "identificador" => "fig0035" "etiqueta" => "Figure 7" "tipo" => "MULTIMEDIAFIGURA" "mostrarFloat" => true "mostrarDisplay" => false "figura" => array:1 [ 0 => array:4 [ "imagen" => "gr7.jpeg" "Alto" => 1442 "Ancho" => 1500 "Tamanyo" => 202900 ] ] "descripcion" => array:1 [ "en" => "<p id="spar0085" class="elsevierStyleSimplePara elsevierViewall">Postoperative radiographs after 1 year and 3D-CT reconstruction of the occipitocervical instrumentation.</p>" ] ] ] "bibliografia" => array:2 [ "titulo" => "References" "seccion" => array:1 [ 0 => array:2 [ "identificador" => "bibs0005" "bibliografiaReferencia" => array:19 [ 0 => array:3 [ "identificador" => "bib0005" "etiqueta" => "1" "referencia" => array:1 [ 0 => array:2 [ "contribucion" => array:1 [ 0 => array:2 [ "titulo" => "International Morquio A Registry: clinical manifestation and natural course of Morquio A disease" "autores" => array:1 [ 0 => array:2 [ "etal" => false "autores" => array:5 [ 0 => "A.M. 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| Year/Month | Html | Total | |
|---|---|---|---|
| 2024 November | 7 | 0 | 7 |
| 2024 October | 31 | 5 | 36 |
| 2024 September | 55 | 22 | 77 |
| 2024 August | 34 | 8 | 42 |
| 2024 July | 53 | 3 | 56 |
| 2024 June | 27 | 5 | 32 |
| 2024 May | 33 | 7 | 40 |
| 2024 April | 45 | 8 | 53 |
| 2024 March | 50 | 6 | 56 |
| 2024 February | 41 | 8 | 49 |
| 2024 January | 69 | 10 | 79 |
| 2023 December | 52 | 7 | 59 |
| 2023 November | 60 | 7 | 67 |
| 2023 October | 82 | 8 | 90 |
| 2023 September | 24 | 8 | 32 |
| 2023 August | 29 | 8 | 37 |
| 2023 July | 38 | 6 | 44 |
| 2023 June | 39 | 4 | 43 |
| 2023 May | 80 | 6 | 86 |
| 2023 April | 75 | 4 | 79 |
| 2023 March | 47 | 5 | 52 |
| 2023 February | 51 | 6 | 57 |
| 2023 January | 51 | 7 | 58 |
| 2022 December | 43 | 3 | 46 |
| 2022 November | 33 | 5 | 38 |
| 2022 October | 27 | 9 | 36 |
| 2022 September | 41 | 17 | 58 |
| 2022 August | 40 | 11 | 51 |
| 2022 July | 26 | 6 | 32 |
| 2022 June | 38 | 10 | 48 |
| 2022 May | 26 | 11 | 37 |
| 2022 April | 31 | 8 | 39 |
| 2022 March | 52 | 10 | 62 |
| 2022 February | 32 | 7 | 39 |
| 2022 January | 29 | 4 | 33 |
| 2021 December | 17 | 9 | 26 |
| 2021 November | 19 | 9 | 28 |
| 2021 October | 23 | 12 | 35 |
| 2021 September | 11 | 9 | 20 |
| 2021 August | 9 | 7 | 16 |
| 2021 July | 12 | 7 | 19 |
| 2021 June | 14 | 7 | 21 |
| 2021 May | 8 | 5 | 13 |
| 2021 April | 30 | 24 | 54 |
| 2021 March | 19 | 11 | 30 |
| 2021 February | 12 | 14 | 26 |
| 2021 January | 11 | 12 | 23 |
| 2020 December | 1 | 0 | 1 |
| 2018 February | 8 | 1 | 9 |
| 2018 January | 11 | 2 | 13 |
| 2017 December | 12 | 1 | 13 |
| 2017 November | 17 | 1 | 18 |
| 2017 October | 14 | 3 | 17 |
| 2017 September | 22 | 3 | 25 |
| 2017 August | 16 | 5 | 21 |
| 2017 July | 19 | 3 | 22 |
| 2017 June | 13 | 16 | 29 |
| 2017 May | 27 | 5 | 32 |
| 2017 April | 18 | 7 | 25 |
| 2017 March | 19 | 19 | 38 |
| 2017 February | 35 | 10 | 45 |
| 2017 January | 6 | 4 | 10 |
| 2016 December | 13 | 8 | 21 |
| 2016 November | 8 | 7 | 15 |
| 2016 October | 0 | 2 | 2 |
| 2016 September | 0 | 2 | 2 |
| 2016 August | 0 | 2 | 2 |
| 2016 July | 0 | 3 | 3 |
| 2016 May | 0 | 3 | 3 |
| 2016 March | 0 | 1 | 1 |
| 2016 February | 0 | 12 | 12 |
| 2016 January | 0 | 3 | 3 |
| 2015 December | 0 | 3 | 3 |
| 2015 November | 0 | 6 | 6 |
| 2015 October | 0 | 9 | 9 |
| 2015 September | 0 | 3 | 3 |
| 2015 August | 0 | 1 | 1 |
| 2015 July | 0 | 4 | 4 |
| 2015 June | 0 | 3 | 3 |
| 2015 May | 0 | 1 | 1 |
| 2015 April | 0 | 1 | 1 |
| 2015 March | 0 | 1 | 1 |
| 2015 January | 0 | 2 | 2 |
| 2014 November | 0 | 1 | 1 |
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