title: Predictive factors relating to prognosis of anterior decompressive surgery for proximal-type cervical spondylotic amyotrophy.
abstract: OBJECTIVE
  Cervical spondylotic amyotrophy (CSA) is a relatively rare disorder. This study was conducted to elucidate the prognosis of proximal-type CSA after anterior decompressive surgery by evaluating clinical factors and imaging findings.
  
  
  METHODS
  Anterior decompressive surgery was performed in 40 patients with proximal-type CSA between March 2000 and December 2011. Patients were classified into 2 categories based on axial T2-weighted magnetic resonance imaging (MRI) findings: "nerve root compression (NRC)", with nerve root compressed at the intervertebral foramen, and "spinal cord compression (SCC)" with spinal cord compressed at the medial or paramedial site of spinal canal. Manual muscle testing (MMT) was used to evaluate the surgical effect. Scapular, deltoid, and biceps brachii muscles of the affected side were tested and the sum scores were calculated. Clinical factors and imaging findings, such as age, duration of disease, preoperative MMT grade, number of affected levels and signal intensity changes of spinal cord, were collected to analyze prognostic factors.
  
  
  RESULTS
  After anterior decompressive surgery, 30 patients (75%) showed an improvement. NRC was observed in 6 patients and SCC in the rest 34 patients based on MRI findings. All patients (100%) with NRC had an improvement, while only 24 patients (70.6%) with SCC improved. In patients with SCC, there was a significant difference in duration of disease between patients who had an improvement and those who had not (P< 0.01).
  
  
  CONCLUSIONS
  Anterior decompressive surgery is effective in the treatment of most patients with CSA. NRC on MRI may indicate a good surgical outcome. In patients with SCC, a long duration of disease is a risk factor for poor prognosis.
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Ling-De
authors.initials: LD
authors.lastname: Kong
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Lin-Feng
authors.initials: LF
authors.lastname: Wang
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Jing-Tao
authors.initials: JT
authors.lastname: Zhang
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Ying-Ze
authors.initials: YZ
authors.lastname: Zhang
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Wen-Yuan
authors.initials: WY
authors.lastname: Ding
authors.affiliation: Department of Spine Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Shen
mesh_terms: D002574:Cervical Vertebrae / Q000601:surgery; D019299:Decompression, Surgical; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009134:Muscular Atrophy, Spinal / Q000601:surgery*; D011379:Prognosis; D011843:Radiculopathy / Q000473:pathology / Q000601:surgery; D012189:Retrospective Studies; D013117:Spinal Cord Compression / Q000473:pathology / Q000601:surgery; D055009:Spondylosis / Q000601:surgery*
keywords: Cervical spondylotic amyotrophy; anterior surgery; magnetic resonance imaging; predictive factor