title: Segmental motor paralysis after cervical laminoplasty: a prospective study.
abstract: METHODS
  A prospective study.
  
  
  OBJECTIVE
  To examine the prevalence and clinical manifestations of segmental motor paralysis after cervical laminoplasty and to investigate the presence of intramedullary high-signal intensity area (HIA) on postoperative T2-weighted magnetic resonance imaging (MRI).
  
  
  BACKGROUND
  Almost all previous studies had been retrospectively conducted, and MRIs of all subjects, including a control population, have never been investigated.
  
  
  METHODS
  In the 79 patients of the prospective group, the sole examiner evaluated muscle strengths daily for perioperative 3 weeks and MRI scans were performed before and after surgery. Medical records of the 79 consecutive patients before this study were also investigated (control group).
  
  
  RESULTS
  Ten patients from the prospective group developed segmental motor paralysis (proximal in 5, distal in 2, and diffuse in 3), whereas paralysis occurred in only 4 patients from the control group (proximal in 3 and diffuse in 1). On postoperative MRI, a linear HIA corresponded to the paralyzed segment more frequently than a focal or no HIA.
  
  
  CONCLUSIONS
  In the prospective cases, distal or diffuse paralysis was found more frequently than in the retrospective control group. Linear HIAs were significantly more likely to present in the paralyzed segments.
authors.affiliation: Department of Orthopedics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan. sakaurah@ort.med.osaka-u.ac.jp
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sakaura
authors.forename: Noboru
authors.initials: N
authors.lastname: Hosono
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Mukai
authors.forename: Ryutaro
authors.initials: R
authors.lastname: Fujii
authors.forename: Motoki
authors.initials: M
authors.lastname: Iwasaki
authors.forename: Hideki
authors.initials: H
authors.lastname: Yoshikawa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001132:Arm; D002574:Cervical Vertebrae / Q000473:pathology / Q000601:surgery*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D018908:Muscle Weakness / Q000209:etiology / Q000503:physiopathology; D018482:Muscle, Skeletal / Q000503:physiopathology; D019637:Orthopedic Procedures / Q000009:adverse effects*; D010146:Pain / Q000209:etiology / Q000503:physiopathology; D010243:Paralysis / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D011184:Postoperative Period; D015995:Prevalence; D011446:Prospective Studies; D012678:Sensation Disorders / Q000209:etiology / Q000503:physiopathology; D012720:Severity of Illness Index