title: Solid variant of aneurysmal bone cyst of the cervical spine.
abstract: METHODS
  A case of the solid variant of aneurysmal bone cyst affecting the posterior component of the fourth cervical vertebra is reported. Imaging studies showed an expansile destructive lesion. After curettage, autologous iliac bone grafting with posterior fusion was performed. There was no sign of local recurrence 2 years after surgery.
  
  
  OBJECTIVE
  To emphasize the occurrence of the solid variant of aneurysmal bone cyst in the cervical spine.
  
  
  BACKGROUND
  The solid variant of aneurysmal bone cyst is rare, and only 12 cases occurring in the vertebrae, including 3 in the cervical vertebrae, have been reported. The condition is difficult to diagnose radiologically before biopsy or surgery.
  
  
  METHODS
  A 9-year-old girl presented with pain in the nape of the neck without any neurologic deficit. She was found to have the solid variant of aneurysmal bone cyst in the posterior component of the fourth cervical vertebra, which had destroyed the lamina and spinous process. Part of the posterior aspect of the C4 vertebral body was also involved. Curettage of the lesion was performed, and the defect in the posterior component of the vertebra was reconstructed using an autologous iliac bone graft with posterior fusion using a halo vest.
  
  
  RESULTS
  Magnetic resonance imaging disclosed a homogeneous low intensity mass at the lamina, spinous process, and vertebral body of C4 on T1-weighted images. The mass showed heterogeneous high signal intensity on Gd-enhanced images. Histologically, the resected specimen showed predominant fibroblastic proliferation, with minor foci of reactive osteoid formation and an area of osteoclast-like giant cells. Neither cellular atypia nor mitotic figures were evident. There was no sign of local recurrence 2 years after surgery.
  
  
  CONCLUSIONS
  The solid variant of aneurysmal bone cyst should be included in the differential diagnosis of any lytic expansile lesion of the spine, even though it is a destructive lesion. Gd-enhanced magnetic resonance imaging may be helpful for distinguishing the solid variant from conventional aneurysmal bone cyst.
authors.affiliation: Department of Orthopedic Surgery, School of Medicine, Iwate Medical University, Uchimaru 19-1, Morioka 020-8505, Japan.
authors.forename: Michihiro
authors.initials: M
authors.lastname: Suzuki
authors.forename: Takashi
authors.initials: T
authors.lastname: Satoh
authors.forename: Jun
authors.initials: J
authors.lastname: Nishida
authors.forename: Sadafumi
authors.initials: S
authors.lastname: Kato
authors.forename: Tamotsu
authors.initials: T
authors.lastname: Toba
authors.forename: Takehisa
authors.initials: T
authors.lastname: Honda
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Masuda
mesh_terms: D017824:Bone Cysts, Aneurysmal / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery / Q000628:therapy; D016025:Bone Transplantation; D001915:Braces; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002648:Child; D003131:Combined Modality Therapy; D003475:Curettage; D005260:Female; D006801:Humans; D007103:Immobilization; D008279:Magnetic Resonance Imaging; D019547:Neck Pain / Q000209:etiology; D010014:Osteolysis / Q000209:etiology; D012074:Remission Induction; D013122:Spinal Diseases / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery / Q000628:therapy; D013123:Spinal Fusion; D014057:Tomography, X-Ray Computed