title: Single-level instrumented mini-open transforaminal lumbar interbody fusion in elderly patients.
abstract: OBJECTIVE
  The purpose of this study was to analyze the surgical outcomes in cases involving elderly patients who underwent single-level instrumented mini-open transforaminal lumbar interbody fusion (TLIF).
  
  
  METHODS
  The authors performed a retrospective review of 27 consecutive cases involving elderly patients (> or = 65 years of age) who underwent single-level instrumented mini-open TLIF and were followed up for at least 3 years. Degenerative spondylolisthesis was diagnosed in 16 patients, stenosis with instability in 8, and lytic spondylolisthesis in 3. All cases were Grade I or II based on the American Society of Anesthesiologists' classification system. Clinical outcomes were assessed using a visual analog scale, the Oswestry Disability Index, and patients' subjective satisfaction. Sagittal balance, bone union, and adjacent segment degeneration (ASD) were assessed using plain radiography and 3D CT.
  
  
  RESULTS
  The mean age of patients at the time of surgery was 69.3 years (range 65-80 years). Minor complications occurred in 2 patients (7.4%) in the perioperative period. At a mean follow-up duration of 38.6 months (range 36-42 months), clinical success was achieved in 88.9% of cases. The mean segmental lordosis and sacral tilt significantly increased after surgery (from 11.9 and 33.5 degrees to 13.9 and 37.2 degrees , p = 0.024 and p = 0.001, respectively). Solid fusion was achieved in 77.8% of the patients. Adjacent segment deterioration was found in 44.4% of the patients. No patients underwent revision surgery due to nonunion or ASD. The development of ASD was significantly related to postoperative sacral tilt (p = 0.006).
  
  
  CONCLUSIONS
  Single-level instrumented mini-open TLIF yielded good clinical and radiological outcomes with a low complication rate in elderly patients.
authors.affiliation: Department of Neurosurgery, Wooridul Spine Hospital, Seoul, Korea.
authors.forename: Dong Yeob
authors.initials: DY
authors.lastname: Lee
authors.forename: Tag-Geun
authors.initials: TG
authors.lastname: Jung
authors.forename: Sang-Ho
authors.initials: SH
authors.lastname: Lee