Introduction: MIS techniques have been increasingly applied to treat ASD. MIS, OPEN, and HYB techniques were compared in an ASD patient population through propensity matching.
Methods: 280 patients in 2 prospective databases (MIS n=85; OPEN n=195) were retrospectively reviewed, divided into 3 approaches (OPEN, MIS, and HYB) and propensity matched for age, ODI, SVA and major Cobb (p>0.05). Inclusion criteria: age>45, Cobb >20°, min 1yr follow-up. Groups: 1)MIS- standalone lateral transpsoas (LIF), LIF with MIS posterior pedicle screws (PPS), and MIS TLIF (n=31). 2)HYB- LIF with open PPS(n=31); 3)OPEN- Open PPS +/- interbody (n= 31).
Results: At 1yr there was no difference in major Cobb (MC), PI-LL, PT or SVA. OPEN had more LL (52.5) at 1yr than MIS(40.5; p<0.001) and HYB (44.4; p=0.023). There was no difference between group at preop or 1yr in Schwab-SRS classification. All groups reached significant decrease in ODI at 1yr. Within each group there was significant improvement in MC, LL, and PI-LL. MIS had significantly less EBL and transfusion (563cc; 32.3%) than HYB or OPEN (1802cc, 58.1% and 1974cc, 83.9%; p<0.003). OR time was longer with HYB (735 min) than MIS and OPEN (461 and 407 min; p<0.001). OPEN was associated with more levels fused (9.3) than MIS (4.8; p<0.001) and HYB (7; p=0.03). Open surgery was extended to the pelvis 80.6% vs. 22.6% and 67.7% for MIS and HYB (p<0.001). Major complications occurred in 12% of MIS, 33.3% HYB, and 44.8% OPEN (p=0.032).
Conclusions: This is the first study to evaluate different surgical techniques to treat patients with statistically similar disability and spine deformity. All groups resulted in significant improvement in ODI. MIS was associated with less EBL, transfusion, fusion levels, shorter OR time and a favorable complication profile compared to HYB and OPEN. Our data supports the role of MIS for ASD.
Patient Care: Improve our understanding of surgical treatment strategies for adults with spinal deformity.
Learning Objectives: By the conclusion of this session, participants should be able to: (1) Understand that minimally invasive options are available for the surgical treatment of adult spinal deformity; (2) Appreciate that minimally invasive approaches may offer some advantages over the traditional open approaches for the correction of adult deformity, including less blood loss, reduced need for blood transfusion, need to fuse fewer spinal levels, and shorter operative times.