title: Surgical simulation of circumferential osteotomy and correction of cervico-thoracic kyphoscoliosis for an irreducible old C6-C7 fracture dislocation.
abstract: BACKGROUND
  Many different surgical procedures have been employed in the treatment of fracture dislocation at the middle to lower cervical spine. However, consistent protocols and procedures have not been fully established for the surgical correction of an irreducible old cervical fracture dislocation associated with spinal deformity.
  
  
  METHODS
  We report a case of irreducible cervical fracture dislocation and kyphoscoliosis, in which surgical simulation using a three-dimensional full-scale model was useful for circumferential corrective osteotomy at the C6-C7 level. A 56-year-old man was diagnosed with an irreducible fracture dislocation at the C6-C7 level 2 months after a motor vehicle accident. He showed torticollis, and complained of severe pain in his neck and left upper arm. Radiographic examinations revealed that the C6 vertebra was translated anteriorly and laterally to the C7 vertebra. A bony union had progressed at the fracture site, showing rigid cervico-thoracic kyphoscoliosis. To assist in the preoperative planning, we created a three-dimensional, full-scale model from the patient's computed tomography data. Using the model, we performed a simulation of the planned circumferential corrective osteotomy at the C6-C7 level.
  
  
  RESULTS
  Through the simulation, we could evaluate the deformed bony structures around the vertebral arteries at the C6-C7 level accurately. At the time of the actual surgery, corrective osteotomy combined with spinal fusion (C5-T2) with a pedicle screw-rod system was accomplished successfully without any neurovascular complications. After surgery, the patient experienced relief from pain, and his neck posture became normal.
  
  
  CONCLUSIONS
  Surgical simulation using a three-dimensional, full-scale model was useful for improving the accuracy and safety of circumferential corrective osteotomy of the cervical spine.
authors.affiliation: Spine Section, Department of Orthopaedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba 260-8677, Japan. masashiy@faculty.chiba-u.jp
authors.forename: Masashi
authors.initials: M
authors.lastname: Yamazaki
authors.forename: Akihiko
authors.initials: A
authors.lastname: Okawa
authors.forename: Ryo
authors.initials: R
authors.lastname: Kadota
authors.forename: Chikato
authors.initials: C
authors.lastname: Mannoji
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Miyashita
authors.forename: Masao
authors.initials: M
authors.lastname: Koda
mesh_terms: D000063:Accidents, Traffic; D001863:Bone Screws; D002574:Cervical Vertebrae / Q000293:injuries* / Q000473:pathology / Q000601:surgery*; D019299:Decompression, Surgical / Q000295:instrumentation / Q000379:methods; D006801:Humans; D016268:Internal Fixators; D007738:Kyphosis / Q000209:etiology / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D019547:Neck Pain / Q000209:etiology; D010027:Osteotomy / Q000295:instrumentation / Q000379:methods*; D011183:Postoperative Complications; D011300:Preoperative Care; D019651:Plastic Surgery Procedures / Q000295:instrumentation / Q000379:methods*; D012600:Scoliosis / Q000209:etiology / Q000473:pathology / Q000601:surgery; D013119:Spinal Cord Injuries / Q000209:etiology / Q000517:prevention & control / Q000601:surgery; D013121:Spinal Curvatures / Q000209:etiology / Q000473:pathology / Q000601:surgery*; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods; D014057:Tomography, X-Ray Computed / Q000379:methods; D014103:Torticollis / Q000209:etiology; D016896:Treatment Outcome