title: Functional computed tomography scanning for evaluating fusion status after anterior cervical decompression fusion.
abstract: BACKGROUND
  Nonunion is a major complication of anterior cervical fusion that causes poor outcomes and occasionally requires additional operative intervention. The purpose of this study is to evaluate the accuracy of functional computed tomography (CT) scanning for determining fusion status after anterior cervical fusion by comparing with functional radiographs.
  
  
  METHODS
  The fusion status in 59 patients treated by anterior cervical fusion was assessed by functional radiography and functional CT scanning at 6 and 12 months after surgery. Fusion rates and clinical symptoms were evaluated. Fusion on functional radiography was defined as less than 2 mm of motion between adjacent spinous processes and a particular bony trabeculation on functional CT; fusion was defined as nonexistence of a clear zone or a gas pattern and a particular bone connection on reconstructed sagittal-view images.
  
  
  RESULTS
  Functional radiographs demonstrated solid fusion in 83.9% at 6 months and 91.1% at 12 months postoperatively; functional CT showed solid fusion in 55.3 and 78.6%, respectively. The fusion rate detected on functional CT images was significantly lower than that on functional radiographs at each period. At 6 months postoperatively, patients with incomplete union on functional CT were more likely to have neck pain than those who had complete union on functional CT. (46.2 vs 13.3%, P < 0.05) CONCLUSION: Functional CT can detect nonunion more clearly than functional radiography. At 6 months postoperatively, patients with incomplete union on functional CT images were likely to have more neck pain. Functional CT may allow accurate detection of symptomatic nonunion after anterior cervical fusion.
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan. orthochida@gmail.com.
authors.forename: Jun
authors.initials: J
authors.lastname: Ouchida
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
authors.forename: Yasutsugu
authors.initials: Y
authors.lastname: Yukawa
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
authors.forename: Keigo
authors.initials: K
authors.lastname: Ito
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Machino
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
authors.forename: Taro
authors.initials: T
authors.lastname: Inoue
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tomita
authors.affiliation: Department of Orthopedic Surgery, Chubu Rosai Hospital, Japan Labor Health and Welfare Organization, 1-10-6 Komei, Minato-ku, Nagoya, Aichi, 455-8530, Japan.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kato
mesh_terms: D000328:Adult; D000368:Aged; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D019299:Decompression, Surgical / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013122:Spinal Diseases / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods*; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome
keywords: Anterior cervical fusion; Computed tomography; Functional CT scan; Pseudarthrosis; Radiographic assessment