title: Occipitocervical stabilization using bilateral laminar C2 screws in children with mucopolysaccharidosis IVA.
abstract: OBJECTIVE
  Mucopolysaccharidosis IVA (MPS IVA) is a multisystemic storage disorder. Patient's disability and life expectancy depends upon skeletal complications, including cervical myelopathy due to upper cervical compression or instability. Posterior decompression followed by occipitocervical fixation or C1-2 fusion are the most frequently recommended surgical interventions. The bony elements of C1 and C2 are often inadequately developed making routine screw insertion difficult. The main purpose of this work was to present novel technique of occipitocervical fixation using two C2 laminar screws.
  
  
  METHODS
  Four children with MPS IVA underwent decompression and C0-C2 instrumented fusion using two C2 bilateral laminar screws. The dimensions of the C2 lamina were measured. Clinical and radiological results were monitored prospectively for a minimum 3 years.
  
  
  RESULTS
  The mean laminar length was 24 ± 1.15 mm, width 6.15 ± 0.55 mm and height 7.4 ± 0.6 mm. Patients remained in a stable neurological condition. The mean antero-posterior diameter of the spinal canal on the pre-operative MR was 6.2 ± 0.74 mm and it was enlarged to 11.4 ± 0.8 mm after 3 years. All screws were placed adequately. In all patients, the control CT scan 2 years post-operatively revealed a stable position of the treated segments, but solid bony fusion was not registered in any patient.
  
  
  CONCLUSIONS
  Decompression and fusion of the upper cervical spine is a generally accepted approach to treat upper cervical spine instability and myelopathy in MPS IVA patients. The feasibility and the suitability of the technique of C0-C2 stabilization using bilateral C2 laminar screws have been presented.
authors: Department of Neurosurgery, Military University Hospital and First Faculty of Medicine, Charles University in Prague, U vojenske nemocnice 1200, Prague 6, 169 02, Czech Republic. petr.vanek@uvn.cz.
authors: Petr
authors: P
authors: Vanek
authors: Department of Pediatric Neurosurgery, Thomayer's Teaching Hospital, Prague, Czech Republic.|Department of Pediatric Surgery and Traumatology, Thomayer's Teaching Hospital, Prague, Czech Republic.
authors: Helena
authors: H
authors: Homolkova
authors: Department of Neurosurgery, Military University Hospital and First Faculty of Medicine, Charles University in Prague, U vojenske nemocnice 1200, Prague 6, 169 02, Czech Republic.
authors: Vladimir
authors: V
authors: Benes
authors: Department of Pediatrics, General Faculty Hospital and First Faculty of Medicine, Charles University in Prague, Prague, Czech Republic.
authors: Jiri
authors: J
authors: Zeman
mesh_terms: D000293:Adolescent; D001269:Atlanto-Occipital Joint / Q000601:surgery*; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000601:surgery*; D002648:Child; D019299:Decompression, Surgical / Q000295:instrumentation / Q000379:methods; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009085:Mucopolysaccharidosis IV / Q000150:complications*; D013117:Spinal Cord Compression / Q000175:diagnosis / Q000209:etiology / Q000601:surgery; D013123:Spinal Fusion / Q000295:instrumentation* / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods
keywords: Laminar; Mucopolysaccharidosis; Screw; Stabilization