Introduction: Average clinical outcomes are improved with surgery for selected ASD patients, but these outcomes span a broad range. Our objective was to compare ASD patients with best vs worst clinical outcomes to identify distinguishing factors.
Methods: Multicenter, prospective study of consecutive ASD patients treated operatively. Inclusion criteria included: age>18yr, ASD and min 2yr follow-up. Best vs worst outcomes patients were compared separately based on SRS-22 and ODI. Only those with BL SRS-22<3.5 or ODI>30 were included to minimize floor effect. Best and worst outcomes were defined for SRS-22 (>4.5 and <2.5) and ODI (<15 and >50).
Results: Of 227 patients, 187 had SRS-22<3.5 (25 best and 27 worst outcomes) and 162 had ODI>30 (43 best and 51 worst outcomes). Based on SRS-22, compared with best outcomes patients, those with worst outcomes had greater BL SRS-22 (p<0.0001), higher prevalence of BL depression (p<0.001), greater comorbidities (p=0.012), greater prevalence of prior surgery (p=0.007), higher complication rate (p=0.012) and worse BL deformity (SVA [p=0.045], PI-LL mismatch [p=0.034]). The best-fit multivariate model for SRS-22 included BL SRS-22 (p=0.033), BL depression (p=0.012) and complications (p=0.030). Based on ODI, compared with best outcomes patients, those with worst outcomes had greater BL ODI (p<0.001), greater BL BMI (p=0.002), higher prevalence of BL depression (p<0.028), greater BL SVA (p=0.016), higher complication rate (p=0.02) and greater 2yr SVA (p<0.001) and PI-LL mismatch (p=0.042). The best-fit multivariate model for ODI included BL ODI (p<0.001), 2yr SVA (p=0.014) and BL BMI (p=0.037). Age did not distinguish best vs worst outcomes for SRS-22 or ODI (p>0.1).
Conclusions: Factors distinguishing best vs worst outcomes for ASD surgery included several patient factors (BL depression, BMI, comorbidities and disability), as well as residual deformity (2yr SVA) and complications. These findings suggest factors that may warrant further attention in order to achieve optimal surgical outcomes for ASD.
Patient Care: This study will improve patient care by identifying factors that may warrant further attention in order to achieve optimal surgical outcomes for ASD.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) identify the factors distinguishing between the best and worst outcomes