Introduction: ICU and hospital length of stay (LOS) after adult spinal deformity (ASD) surgery is costly. We aim to compare MIS vs. open surgery for the treatment of mild to moderate ASD (pre-op SVA < 6 cm) with respect to post-op ICU and hospital LOS.
Methods: A retrospective review of 2 multi-center ASD databases with the same inclusion criteria was conducted (MIS-retrospective; OPEN-prospective) with minimum 2 year follow up. Patients with minimum 4 levels were included for analysis. Circumferential MIS (CMIS) patients were propensity-matched by levels fused to the OPEN cohort.
Results: Matching resulted in 88 patients for analysis (44 CMIS, 44 OPEN). CMIS were older (61 v 53 yrs, p=0.005). Mean levels fused were 6.5 in MIS and 7.1 in OPEN (p=0.368). Preoperative lordosis was higher in OPEN than in CMIS (42.7º vs. 40.9º, p=0.016), and preop VAS back pain was greater in OPEN than in CMIS (7 vs. 6.2, p=0.033). Other factors such as pre- and postop PT, PI-LL, SVA, ODI, and VAS leg pain were no different between groups. EBL was 534cc in MIS and 1211cc in OPEN (p<0.001). Transfusion rate was less in MIS (27.3% vs. 70.5%, p<0.001). O.R. time for MIS vs. OPEN was 433 min vs. 379 min (p=0.15). Average ICU stay was 0.6 days for MIS patients and 1.2 days for OPEN patients (p=0.009). Overall hospital LOS was 7.9 days for MIS vs 9.6 for OPEN (p=0.804).
Conclusions: For patients undergoing surgical correction of mild to moderate spinal deformity CMIS surgery had a significantly lower EBL and shorter ICU stay. Overall LOS was shorter and clinically relevant despite not reaching statistical significance. This shorter intensity of stay may reduce overall cost.
Patient Care: To assess the impact of minimally invasive surgery on adult deformity.
Learning Objectives: Understanding outcomes of minimally invasive adult deformity surgery versus open surgery.