231. Adult spinal deformity patients who undergo staged surgery within three months have equivalent timeline to functional recovery as those with non-staged surgery

Abstract

BACKGROUND CONTEXT A potential limitation of staging surgery in adult spinal deformity (ASD) patients is delayed functional recovery; however, this finding has not been well demonstrated. PURPOSE Our purpose was to demonstrate that ASD patients who undergo staged surgery have equivalent timeline to functional recovery compared to patients who have non-staged surgery. STUDY DESIGN/SETTING Retrospective review of a single-center database. PATIENT SAMPLE A total of 87 ASD patients (>5 levels fused) and fusion to the pelvis. OUTCOME MEASURES Our primary outcome was reaching minimal clinically important difference (MCID) in the Scoliosis Research Society (SRS-22r) Activity domain. METHODS Minimal clinically important difference (MCID) was defined as 0.4-point improvement in SRS-22r Activity. Patients were excluded with staged procedure greater than 3 months after the index procedure, or who had less than 2-year follow-up and did not meet MCID. Using a cox proportional hazard model, we controlled for primary vs revision surgery, number of levels fused, age, gender and baseline functional scores. Our study was powered to detect a relative hazard ratio (HR) of 0.53, β = 0.20. RESULTS Mean age of patients was 61 ± 11 years, 78% females, SVA of 10.7 ± 9.5cm. Mean levels fused were 8.8 (range 6-18). 38 (46%) of patients had a second-stage surgery, while 44 (54%) had non-staged surgery. Mean preoperative SRS-22r Activity was 2.8 ± 0.6. Staged and non-staged groups had similar gender, age, baseline SRS-22r Activity, (p>0.05). Patients with a staged surgery did not have decreased likelihood of reaching SRS-22r Activity MCID at compared to patients without a staged surgery (HR 0.74, 95% CI: 0.41 – 1.36). Median time to reaching SRS-22r Activity MCID was 191 days in patients with a staged procedure and 181 days in patients with unstaged surgery, p=0.75. CONCLUSIONS ASD patients undergoing staged surgery within 3 months achieve clinically important functional improvement with the same frequency and time interval as patients without staged surgery. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.