51. Is percutaneous pedicle screw (PPS) fixation associated with minimized risk of perioperative proximal junctional kyphosis (PJK) in adult spinal deformity?

Abstract

BACKGROUND CONTEXT Numerous strategies are used to minimize PJK in (ASD). The use of PPS is one such strategy. Studying this topic is difficult as there is a lack of homogeneity in the patient population being studied. PURPOSE Investigate if PPS minimizes the risk of perioperative PJK compared to traditional open techniques. STUDY DESIGN/SETTING Retrospective review of prospective multicenter adult spinal deformity database PATIENT SAMPLE Inclusion criteria are age >18, and one of the following: PT>25, PI-LL>10, or SVA>5 cm. OUTCOME MEASURES NRS leg, ODI, SF-12, EQ5D, SRS-22. METHODS A prospective database was retrospectively reviewed. Inclusion criteria are age >18, and one of the following: PT>25, PI-LL>10, or SVA>5 cm. Patients were grouped as MIS (all PPS no open component) or OPEN. Propensity matching was used to create 2 equal groups controlling for: age, BMI, Preop (PI-LL, PI, TPA), and post op (PI-LL correction and posterior levels fused). PJK was evaluated in 2 groups: Mild (PJK10) 10° change from preop and severe (PJK20) a 20° change, as previously reported. RESULTS A total of 1,023 patients met criteria: 114 MIS and 909 OPEN. MIS were older with higher BMI. No significant difference was found between groups in preop alignment or SRS Schwab classification. OPEN had more levels fused (11.3 vs 5.5), change in PI-LL (14.9 vs 9.3) and LL (16.2 vs 9.7; all p 0.59). PJK20 was 2.6% in OPEN vs 3.9% in MIS at 1YR (p=1). The PJK angle was not different (4.3 v 4.2). MIS had less EBL (510 v 1574 cc; p=0.000) longer OR time (448 v 373 min; p=0.022) and more interbodies (3.4 vs 2.1; p=0.000). There was no difference in rate of revision surgery (14.3% OPEN vs 10.4%). Major complications occurred more frequently in OPEN (23.4% vs 9.1%). CONCLUSIONS While the use of percutaneous fixation intuitively seems protective for PJK, our study found that when controlling for radiographic deformity, deformity correction, demographics and the magnitude of surgical intervention that percutaneous fixation is equivalent to open techniques in rate of perioperative PJK. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.