title: Atlantoaxial instability secondary to eosinophilic granuloma of the axis in adults: long-term follow-up in six cases.
abstract: BACKGROUND
  Eosinophilic granuloma (EG) involving the spine is uncommon in adults. Atlantoaxial instability (AAI) secondary to EG of the axis in adults is an extremely rare clinical condition that can give rise to severe neurologic morbidity or mortality if not treated appropriately. There have been no previous reports on the condition in adults.
  
  
  OBJECTIVE
  To present the outcome and clinical experience for the management of AAI secondary to EG of the axis in adults.
  
  
  METHODS
  A retrospective review study.
  
  
  METHODS
  All adult patients with AAI secondary to EG of the axis who were admitted to the spine service at the study institution between January 1999 and April 2012.
  
  
  METHODS
  Clinical symptoms, neurologic status, radiologic manifestations, treatment, outcome, and/or complications were recorded and analyzed.
  
  
  METHODS
  Six consecutive adults who presented clinical and radiographic manifestations of AAI secondary to EG of axis were treated and monitored. All patients were treated surgically with anterior tumor resection and posterior reconstruction of spinal stability. Oral steroid therapy was administered after surgery as adjuvant therapy.
  
  
  RESULTS
  The mean duration of follow-up was 77 months (range, 37-140 months). The most common radiographic feature was osteolytic destruction of the vertebral body of the axis. All patients had favorable recoveries, with osseous fusion. There were no surgery-related postoperative complications, and neither recurrence nor spinal deformity had occurred by the final follow-up examination.
  
  
  CONCLUSIONS
  Surgical intervention via anterior tumor resection and posterior reconstruction was found to be safe and effective for treating AAI secondary to EG in adults, in terms of recovering neurologic function, improving symptom relief, and reducing the risks resulting from osteolytic destruction. Surgical treatment plus oral steroid therapy can produce beneficial results and definitive local control during the follow-up period.
authors.affiliation: Department of Orthopedics, ChengDu Military General Hospital, 270 Tianhui Rd, Rongdu Ave., ChengDu 610083, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zheng
authors.affiliation: Pharmacy Department, Research Center, ChengDu Military General Hospital, 270 Tianhui Rd, Rongdu Ave., ChengDu 610083, People's Republic of China.
authors.forename: Juan
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Orthopedics, Spine Tumor Center, ChangZheng Hospital, Second Military Medical University, 415 Fengyang Rd, Shanghai 200003, People's Republic of China.
authors.forename: ZhiPeng
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Department of Orthopedics, Spine Tumor Center, ChangZheng Hospital, Second Military Medical University, 415 Fengyang Rd, Shanghai 200003, People's Republic of China. Electronic address: xiaojianruprof@gmail.com.
authors.forename: JianRu
authors.initials: J
authors.lastname: Xiao
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D004803:Eosinophilic Granuloma / Q000150:complications* / Q000000981:diagnostic imaging / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007593:Joint Instability / Q000000981:diagnostic imaging / Q000209:etiology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011859:Radiography; D019651:Plastic Surgery Procedures; D012189:Retrospective Studies; D013123:Spinal Fusion; D016896:Treatment Outcome; D055815:Young Adult
keywords: Adult; Atlantoaxial instability (AAI); Eosinophilic granuloma (EG); Oral steroid therapy; Pathological fracture; Spinal cord compression; Surgical treatment