Lightning Podiums: Spinal Potpourri - 803B

Presented by: P. Passias


P. Passias(1), G. Poorman(1), J. Lurie(2), W. Zhao(3), T. Morgan(2), S. Horn(1), C. Bortz(1), F. Segreto(1), L. Steinmetz(1), N. Frangella(1), S. Bess(4), V. LaFage(5), M. Gerling(1), T. Errico(1)

(1) New York University Langone Orthopedic Hospital, Division of Spinal Surgery, New York, NY, United States
(2) Geisel School of Medicine at Dartmouth, Hanover, NH, United States
(3) Geisel School of Medicine at Dartmouth, Department of Biomedical Data Sciences, Hanover, NH, United States
(4) Rocky Mountain Hospital for Children, Denver, CO, United States
(5) New York University Hospital for Special Surgery, New York, NY, United States


Introduction: Factors relevant in deciding surgical treatment for degenerative spondylolisthesis (DS) include disease state severity and patient quality of life expectations. Some may not be easily appraised by the surgeon. In a prospective trial with nonoperative and operative patients, there are crossovers from the nonoperative group who receive surgery. Identifying and understanding patient characteristics that may influence crossover from nonoperative to operative treatment arms will aid understanding of what motivates patients towards pursuing surgery.

Methods: DS patients randomized to nonoperative care in a prospective, multicenter study were evaluated over 8 years of enrollment. Two cohorts were defined: (1) crossover (CROSS); those who at any point received surgery, and non-crossover (non-CROSS); those who remained nonoperative. A Cox proportional hazards model, modeling time to crossover, was used to explore demographic data, clinical diagnoses, and patient expectations and attitudes after adjusting other variables. A sub-analysis was performed on crossovers within 6 months of enrollment and crossovers after 6 months of enrollment.

Results: 145 randomized nonoperative patients were included, 80 of which crossed over to surgery. In analyzing baseline differences, CROSS patients were younger however there was no significant difference in race, sex, or comorbidities. Without considering treatment preference, Cox proportional hazards modeling described younger age, male sex, and white-race as predictors of crossover. Upon inclusion of treatment preference as a factor, treatment preference and ´problem getting worse´ were the only predictors for crossover. Clinically, stenosis, neurological deficits, and listhesis levels did not show a significant relationship with crossing over. At long-term followup, CROSS showed significantly greater long-term HRQL improvement. The difference was maintained throughout follow-up.

Conclusion: Patient reported outcome scores, neurological symptoms, and diagnoses including listhesis and stenosis severity did not predict patients randomized to nonoperative care crossing over to surgery. Self-evaluation of symptoms and attitudes towards surgery were the only independent predictors of crossover from nonoperative to operative care. Certain demographics crossed over at higher rates, but not independently from attitudes towards surgery.