title: Surgical treatment of failed back surgery syndrome due to sagittal imbalance.
abstract: METHODS
  Retrospective study of consecutive patient series.
  
  
  OBJECTIVE
  To review the etiology of failed back surgery syndrome due to sagittal imbalance and radiographic and clinical results of surgical treatment of these patients who were treated with combined anterior and posterior arthrodesis.
  
  
  BACKGROUND
  Sagittal imbalance after spinal fusion surgery may be a major source of pain and disability. Preventing iatrogenic sagittal imbalance should be a key objective during spinal fusion surgery.
  
  
  METHODS
  Retrospective review of revision spine surgery due to sagittal imbalance treated with combined anterior and posterior spinal arthrodesis in the 19 patients. Outcome variables included radiographic measures of preoperative, postoperative, and follow-up films, and a clinical assessment using the Verbal Analogue Scale (VAS), Oswestry Disability Index, Macnab criteria, Satisfactory Index Instrument, and a review of postoperative complications.
  
  
  RESULTS
  Mean age was 62 years (range, 49-74 years), and mean follow-up was 31 months (range, 24-37 months) for clinical and radiographic outcome variables. The mean preoperative sagittal imbalance was 116 (+/-65) mm, which improved to 32 mm (+/-29) after surgery. Mean lumbar lordosis was 15 degrees (+/-20 degrees) before surgery, and increased to 38 degrees (+/-13 degrees) at follow-up, an increase of 23 degrees. The mean VAS improved from 7.2 (back pain), 6.8 (leg pain) before the surgery to 3 (back pain), 3.2 (leg pain) after the surgery (P < 0.0001). The mean Oswestry Disability Index scores improved from 62 (+/-11) before the surgery to 36 (+/-12) after the surgery (P < 0.0001). Excellent or good outcome was demonstrated in 16 patients (84.2%).
  
  
  CONCLUSIONS
  Most common causes of revision spine surgery due to sagittal imbalance were failure to enhance lumbar lordosis and adjacent disc degeneration after lumbar fusion surgery. These patients were effectively treated with a combined anterior and posterior arthrodesis. Following these surgical treatment, sagittal balance was generally improved with fair-to-good clinical outcomes, high patient satisfaction, and low perioperative complication rates.
authors: Department of Neurosurgery, Gimpo Airport Wooridul Spine Hospital, Seoul, Korea. spinejjs@yahoo.co.kr
authors: Jee-Soo
authors: JS
authors: Jang
authors: Sang-Ho
authors: SH
authors: Lee
authors: Jun-Hong
authors: JH
authors: Min
authors: Seok Kang
authors: SK
authors: Kim
authors: Kyoung-Mi
authors: KM
authors: Han
authors: Dae Hyeon
authors: DH
authors: Maeng
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008141:Lordosis / Q000000981:diagnostic imaging / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011859:Radiography; D013123:Spinal Fusion / Q000379:methods; D013577:Syndrome; D017211:Treatment Failure