title: Appropriate timing of surgical intervention for the proximal type of cervical spondylotic amyotrophy.
abstract: OBJECTIVE
  The purposes of this study were to evaluate the clinical outcome after surgical treatment of patients with the proximal type of cervical spondylotic amyotrophy (CSA) and to explore the appropriate timing for surgical intervention.
  
  
  METHODS
  A retrospective review was performed on a consecutive cohort of 41 patients who underwent surgical treatment for the proximal type of CSA between 1995 and 2011 at the Nagoya Spine Group Hospitals. We collected information regarding age, type of muscle atrophy, preoperative and final manual muscle test, duration of symptoms, high-intensity areas on T2-weighted MRI images, low-intensity areas on T1-weighted MRI images, levels of spinal canal stenosis, the compression lesion site, cervical kyphosis and surgical procedures (laminoplasty, anterior spinal fusion and posterior spinal fusion). Univariate analyses and multivariate logistic regression analysis were performed to identify correlates of a poor outcome. To explore the appropriate timing for performing surgery, we analyzed the data using receiver operating characteristic (ROC) analysis.
  
  
  RESULTS
  The duration of CSA symptoms was 11.6 months on average. The surgical results were excellent for 25 patients, good for six, fair for nine and poor for one. On multivariate logistic regression analysis, the duration of symptoms was statistically associated with a poor surgical outcome (OR 1.393, p = 0.011). ROC analysis demonstrated that 4.3 months from the onset of CSA symptoms was the appropriate time to undergo surgery.
  
  
  CONCLUSIONS
  Our results indicate that we should recommend surgical intervention to patients with the proximal type of CSA within about 4 months after the onset of symptoms if conservative treatment has not been successful.
authors.affiliation: Department of Orthopaedic Surgery, Nagoya University Graduate School of Medicine, 65 Tsurumai, Showa, Nagoya, 4668550, Japan.
authors.forename: Ryoji
authors.initials: R
authors.lastname: Tauchi
authors.forename: Shiro
authors.initials: S
authors.lastname: Imagama
authors.forename: Hidefumi
authors.initials: H
authors.lastname: Inoh
authors.forename: Yasutsugu
authors.initials: Y
authors.lastname: Yukawa
authors.forename: Tokumi
authors.initials: T
authors.lastname: Kanemura
authors.forename: Koji
authors.initials: K
authors.lastname: Sato
authors.forename: Yuji
authors.initials: Y
authors.lastname: Matsubara
authors.forename: Atsushi
authors.initials: A
authors.lastname: Harada
authors.forename: Yoshihito
authors.initials: Y
authors.lastname: Sakai
authors.forename: Yudo
authors.initials: Y
authors.lastname: Hachiya
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kamiya
authors.forename: Hisatake
authors.initials: H
authors.lastname: Yoshihara
authors.forename: Zenya
authors.initials: Z
authors.lastname: Ito
authors.forename: Kei
authors.initials: K
authors.lastname: Ando
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hirano
authors.forename: Akio
authors.initials: A
authors.lastname: Muramoto
authors.forename: Hiroki
authors.initials: H
authors.lastname: Matsui
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Junichi
authors.initials: J
authors.lastname: Ukai
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Ryuichi
authors.initials: R
authors.lastname: Shinjo
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nakashima
authors.forename: Naoki
authors.initials: N
authors.lastname: Ishiguro
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000601:surgery*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018908:Muscle Weakness / Q000209:etiology; D018482:Muscle, Skeletal / Q000503:physiopathology; D009133:Muscular Atrophy / Q000209:etiology; D009134:Muscular Atrophy, Spinal / Q000175:diagnosis / Q000209:etiology / Q000601:surgery*; D012372:ROC Curve; D012189:Retrospective Studies; D055009:Spondylosis / Q000150:complications / Q000175:diagnosis / Q000601:surgery*; D061665:Time-to-Treatment; D016896:Treatment Outcome; D034941:Upper Extremity