The Benefit of Addressing Malalignment in Revision Surgery for Proximal Junctional Kyphosis Following ASD Surgery

Abstract

Study Design. Retrospective cohort study. Objective. Understand the benefit of addressing malalignment in revision surgery for proximal junctional kyphosis (PJK). Summary of Background Data. PJK is a common cause of revision surgery for adult spinal deformity patients. During a revision, surgeons may elect to perform a proximal extension of the fusion, or also correct the source of the lumbopelvic mismatch. Materials and Methods. Recurrent PJK following revision surgery was the primary outcome. Revision surgical strategy was the primary predictor (proximal extension of fusion alone compared with combined sagittal correction and proximal extension). Multivariable logistic regression determined rates of recurrent PJK between the two surgical groups with lumbopelvic surgical correction assessed through improving ideal alignment in one or more alignment criteria [Global Alignment and Proportionality (GAP), Roussouly-type, and Sagittal Age-Adjusted Score (SAAS)]. Results. A total of 151 patients underwent revision surgery for PJK. PJK occurred at a rate of 43.0%, and PJF at 12.6%. Patients proportioned in GAP postrevision had lower rates of recurrent PJK [23% vs. 42%; odds ratio (OR): 0.3, 95% confidence interval (CI): 0.1–0.8, P=0.024]. Following adjusted analysis, patients who were ideally aligned in one of three criteria (Matching in SAAS and/or Roussouly matched and/or achieved GAP proportionality) had lower rates of recurrent PJK (36% vs. 53%; OR: 0.4, 95% CI: 0.1–0.9, P=0.035) and recurrent PJF (OR: 0.1, 95% CI: 0.02–0.7, P=0.015). Patients ideally aligned in two of three criteria avoid any development of PJF (0% vs. 16%, P<0.001). Conclusions. Following revision surgery for PJK, patients with persistent poor sagittal alignment showed increased rates of recurrent PJK compared with patients who had abnormal lumbopelvic alignment corrected during the revision. These findings suggest addressing the root cause of surgical failure in addition to proximal extension of the fusion may be beneficial.

Clinical and Economic Impact of Proximal Junctional Kyphosis on Pediatric and Adult Spinal Deformity Patients

“…Passias et al showed failure to optimize sagittal alignment at the time of revision surgery for PJK led to worse clinical outcomes compared with patients who had their abnormal lumbopelvic mismatch corrected in combination with proximal extension of the fusion construct and showed increased rates of PJK and PJF in the malaligned group. 63 It is also unlikely that biomechanical prophylactic strategies designed to prevent PJK and PJF will be able to offset significant errors in alignment, rendering health care dollars utilized in their deployment futile.…”

Gravity Line–Hip Axis Offset as a Guide for Global Alignment to Prevent Recurrent Proximal Junctional Kyphosis/Failure

“…For recurrent PJK/F, surgical options become limited because of the little room for proximal extension and alignment correction, with clinical and financial burden. 7,8 Therefore, preventing the recurrence of this complication during the initial revision is vital.…”