title: High-grade spondylolisthesis: gradual reduction using Magerl's external fixator followed by circumferential fusion technique and long-term results.
abstract: OBJECTIVE
  To report the results of a cohort of patients treated with this technique high lighting radiological and functional outcomes, discussing also benefits arising from a gradual reduction procedure compared with other techniques.
  
  
  METHODS
  We evaluated nine patients who have undergone high-grade listhesis reduction and circumferential fusion at our institution from 1988 to 2006. Average length of follow-up was 11 years (5-19). Functional outcomes and radiological measurements were recorded and reported.
  
  
  RESULTS
  Slip magnitude was reduced by an average of 2.9 grades (Meyerding classification). Slip angle improved by an average of 66% (p = 0.0001), lumbosacral angle by 47% (p = 0.0002), sacral rotation by 51% (p = 0.0068) and sacral inclination by 47% (p = 0.0055). At the latest follow-up 88.9% had achieved solid fusion. Post-operative 10-point Visual Analogue Score (VAS) for back pain had improved by 70% (p < 0.001) and that for leg pain by 76% (p < 0.001) compared with pre-operative score. Average postoperative Oswestry Disability Index for all patients was 8% (range 0-16%) and that for Low Back Outcome Scores was 56.6 (range 44-70). All components of Short Form 36 Health Survey were greater than 80%. Overall patients' expectations were met in 100%.
  
  
  CONCLUSIONS
  This is an effective and safe technique which addresses the lumbosacral kyphosis and cosmetic deformity without the neurological complications which accompany other reduction and fusion techniques for high-grade spondylolisthesis.
authors.affiliation: Centre for Spinal Studies and Surgery, Nottingham University Hospitals NHS Trust, Queens Medical Centre Campus, Derby Road, Nottingham, NG7 2UH, UK. cvkortho@gmail.com
authors.forename: Christos
authors.initials: C
authors.lastname: Karampalis
authors.forename: Michael
authors.initials: M
authors.lastname: Grevitt
authors.forename: Masood
authors.initials: M
authors.lastname: Shafafy
authors.forename: John
authors.initials: J
authors.lastname: Webb
mesh_terms: D000293:Adolescent; D001416:Back Pain / Q000453:epidemiology; D002648:Child; D004185:Disability Evaluation; D016267:External Fixators; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009985:Orthopedics / Q000379:methods*; D010147:Pain Measurement; D015995:Prevalence; D011859:Radiography; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000295:instrumentation / Q000379:methods*; D013131:Spine / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D013168:Spondylolisthesis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult