title: Surgical outcomes after instrumented lumbar surgery in patients of eighty years of age and older.
abstract: BACKGROUND
  In Taiwan, the life expectancy of an 80-year-old man is 88.4 years and the life expectancy of an 80-year-old woman is 89.8 years. Some of these people will develop symptomatic degenerative lumbar diseases that interfere with an active lifestyle. These older surgical candidates usually ask the surgeon whether it would be safe to undergo surgery. However, there is no literature assessing the outcomes of laminectomy, fusion and posterior fixation for degenerative lumbar diseases in patients older than 80 years. The purpose of this study was to report the surgical outcomes of patients 80 years of age and older who underwent spinal decompression and instrumented lumbar arthrodesis for degeneration lumbar diseases.
  
  
  METHODS
  We retrospectively reviewed patients with degenerative lumbar diseases and spinal stenosis who underwent surgery between January 2010 and December 2012. Inclusion criteria were age greater than or equal to 80 years, decompression with instrumented lumbar arthrodesis, and at least 2 years of follow-up. Totally 89 patients were studies. Clinical outcomes were evaluated according to the Oswestry Disability Index (ODI) and visual analogue scale (VAS) of leg and back pain. Plain radiographs (lateral, anteroposterior, and flexion-extension) were used to assess the status of fusion and implant-related complications. Every complication during admission and any implant-related or failed-back syndrome requiring a second surgery was documented. T test and Fisher's exact test were used for statistical analysis.
  
  
  RESULTS
  Five patients were lost to follow-up, and another 12 died during the follow-up period. One patient died due to cerebral stroke just 2 days after surgery, and the other 11 patients passed away 3 months to 4 years postoperatively. In all, 72 patients had an adequate follow-up: 44 were female and 28 were male. The average age at surgery was 82.5 ± 2.6 years (80 to 93); 63 patients underwent their first lumbar surgery, and nine patients received a second surgery. Patients underwent arthrodesis surgeries were from a single-level to a 7-level. Four patients developed complications (5.6 %, 4/72). At the final follow-up, the average ODI score was lower than the preoperative score (30.0 vs. 61.8) (p < 0.001). The average VAS score also showed improvement (leg: p < 0.001; back: p < 0.001). Forty-three patients were classified as "satisfied", and 29 were "dissatisfied". Longer operation time (p = 0.014) and development of complications (p = 0.049) were related to poor clinical results. Radiographic follow-up showed that 53 patients had solid union, ten had a probable union, and nine had pseudarthrosis. More surgical segments led to a greater chance of pseudarthrosis (2.0 ± 0.9 vs 3.0 ± 1.8, p = 0.003).
  
  
  CONCLUSIONS
  Longer instrumented segments and development of complications contributed to worse clinical and radiographic outcomes. With proper patient selection, posterior decompression with instrumented fusion can be safe and effective for patients 80 years of age and older with degenerative lumbar conditions.
authors.affiliation: Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Bone and Joint Research Center, Chang Gung University, No._5, Fu-Shin Street, Kweishian, Taoyuan, 333, Taiwan. jcl1265@adm.cgmh.org.tw.
authors.forename: Jen-Chung
authors.initials: JC
authors.lastname: Liao
authors.affiliation: Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Bone and Joint Research Center, Chang Gung University, No._5, Fu-Shin Street, Kweishian, Taoyuan, 333, Taiwan.
authors.forename: Ping-Yeh
authors.initials: PY
authors.lastname: Chiu
authors.affiliation: Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Bone and Joint Research Center, Chang Gung University, No._5, Fu-Shin Street, Kweishian, Taoyuan, 333, Taiwan.
authors.forename: Wen-Jer
authors.initials: WJ
authors.lastname: Chen
authors.affiliation: Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Bone and Joint Research Center, Chang Gung University, No._5, Fu-Shin Street, Kweishian, Taoyuan, 333, Taiwan.
authors.forename: Lih-Hui
authors.initials: LH
authors.lastname: Chen
authors.affiliation: Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Bone and Joint Research Center, Chang Gung University, No._5, Fu-Shin Street, Kweishian, Taoyuan, 333, Taiwan.
authors.forename: Chi-Chien
authors.initials: CC
authors.lastname: Niu
keywords: Degenerative lumbar spine; Elderly; Instrumented fusion; Outcomes