Long segment fusion for adult degenerative spinal deformity: outcomes and distal segment complications

English Keywords:Adult spinal deformity  Degenerative scoliosis  Coronal balance  Sagittal balance  Pelvic fixation

English Abstract:

  【Abstract】 Objectives: To investigate the outcomes of long instrumentation in adult degenerative spinal deformity, and to explore the rate of distal segment complications. Methods: Adult spinal deformity patients who underwent posterior surgery in our institution between January 2010 and January 2015 were retrospectively reviewed. Inclusion criteria were age more than fifty, either coronal Cobb angle >20° or sagittal balance(SVA) >5cm, more than 4 lumbar segments fixation, at least 12 months follow-up. Demographic data, Oswestry disable index(ODI), SF-12 PCS scores, radiographic parameters and distal segment complications were analyzed. Results: Seventy-four patients were evaluated in this study, 43 cases stopped at L5, 22 cases at sacrum and 9 cases at ilium. The average follow-up time was 28.8 months(range, 12-64 months). Radiographic parameters including Cobb angle, CSVL, SVA, PI-LL, PT improved significantly at last follow-up in each group; ODI and SF-PCS scores changed significantly as well. Distal segment complication rate was 29.7%(22/74) totally. There was significant difference in distal segmental complication rate between patients who saved L5/S1 and fused L5/S1(39.6% vs. 16.1%). Saving L5/S1 disc was an independent risk factor of distal segment complication(P=0.03). Conclusions: Posterior long segment instrumentation and fusion for adult degenerative spinal deformity can improve the patient′s health related quality of life score and obtain satisfying clinic outcome. Saving L5/S1 disc may lead to high risk of distal segmental complication.