title: Anterior expandable strut cage replacement for osteoporotic thoracolumbar vertebral collapse.
abstract: OBJECTIVE
  The authors investigated the usefulness of using an expandable cage strut in anterior reconstruction after osteoporotic vertebral collapse in patients with neurological deficits.
  
  
  METHODS
  Twenty-eight patients who had undergone expandable cage strut-augmented anterior thoracolumbar reconstruction participated in a follow-up review for a mean of 4.9 years. Radiographs were reviewed for kyphosis, lateral tilt of the implant, cage subsidence, the presence of a solid fusion mass, and instrumentation failure. Changes in neurological status and visual analog scale (VAS) pain score, as well as technique-related complications, were examined. The mean angles +/- the standard deviations of kyphosis correction 4 to 6 weeks after surgery and at final follow-up examination were 10.4 +/- 7.6 degrees and 5.6 +/- 6.0 degrees, respectively. The mean subsidence of the expandable cage within the adjacent vertebrae was 2.5 +/- 3.0 mm at the final follow-up examination. Neurological improvement at the final follow up was more significant in patients with Type I (wedge-type) than Type 2 (flat-type) (p = 0.037) or Type 3 (concave-type) (p = 0.006) vertebral collapse. Follow-up VAS scores were significantly higher in patients with Type 1 than Type 3 collapse (p = 0.012). In all cases the authors observed solid union with incorporation of the cage. There were no surgery-related complications.
  
  
  CONCLUSIONS
  An expandable titanium cage strut seems useful in vertebral body replacement in patients with osteoporotic thoracolumbar collapse. Favorable results were obtained in cases of Type I collapse (wedge type) in which the middle and posterior columns remained comparatively intact.
authors.affiliation: Department of Orthopedics and Rehabilitation Medicine, Fukui University School of Medicine, Fukui, Japan. kuchida@fmsrsa.fukui-med.ac.jp
authors.forename: Kenzo
authors.initials: K
authors.lastname: Uchida
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nakajima
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Kokubo
authors.forename: Takafumi
authors.initials: T
authors.lastname: Yayama
authors.forename: Ryuichiro
authors.initials: R
authors.lastname: Sato
authors.forename: Godfrey
authors.initials: G
authors.lastname: Timbihurira
authors.forename: Hisatoshi
authors.initials: H
authors.lastname: Baba
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D016268:Internal Fixators; D008159:Lumbar Vertebrae / Q000293:injuries*; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000209:etiology; D010024:Osteoporosis / Q000150:complications*; D011859:Radiography; D012189:Retrospective Studies; D016103:Spinal Fractures / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery*; D013123:Spinal Fusion / Q000295:instrumentation*; D013904:Thoracic Vertebrae / Q000293:injuries*; D016896:Treatment Outcome