Effect of Vertebroplasty at the Upper Instrumented Vertebra and Upper Instrumented Vertebra +1 for Prevention of Proximal Junctional Failure in Adult Spinal Deformity Surgery: A Comparative Matched-Cohort Study

Abstract

This study aimed to compare radiographic outcomes of adult spinal deformity (ASD) surgery with or without 2-level prophylactic vertebroplasty (PVP) at the uppermost instrumented vertebra (UIV) and the vertebra 1 level proximal to the UIV. This retrospective 1:2 matched-cohort comparative study enrolled 2 groups of patients undergoing ASD surgery, including 28 patients with PVP (PVP group) and 56 patients without PVP (non-PVP group), in 3 institutes between 2012 and 2015. The primary outcome measure was the incidence of proximal junctional kyphosis (PJK), proximal junctional failure (PJF), and proximal junctional fracture (PJFX). The secondary outcome measure were radiologic outcomes between PVP segments and non-PVP segments. Between the PVP group and non-PVP group, no significant differences were found in the incidence of PJK (13 [46.4%] vs. 26 [46.4%]; P= 1.000), PJF (11 [39.3%] vs. 18 [32.1%]; P= 0.516), and PJFX (11 [39.3%] vs. 18 [32.1%]; P= 0.516). The number of the PJFX segments was 16 and 33 in PVP segments and non-PVP segments, respectively. Until revision surgery or final follow-up, the PJFX had progressed in 24 non-PVP segments (82.7%), but not in PVP segments. The PJFX progression in all PVP segments stopped near the PVP mass at the final follow-up. Reoperation as a result of PJFX was performed in 1 patient (3.6%) and 8 patients (14.3%) in the PVP and non-PVP groups, respectively. PVP at UIV and vertebra 1 level proximal to the UIV cannot prevent PJK, PJF, and PJFX; however, it plays a positive role by delaying their progression. Furthermore, PVP tends to lower the reoperation rate after PJFX in ASD surgery.