Propensity score matched analysis of a multi-center prospective adult spinal deformity
Evaluate if surgical implant prophylaxis
combined with avoidance of sagittal overcorrection more effectively prevents proximal junctional failure
(PJF) than use of surgical implants alone.
Summary of Background Data.
PJF is a severe form of proximal junctional kyphosis
(PJK). Efforts to prevent PJF have focused on use of surgical implants. Less information exists on avoidance of overcorrection of age-adjusted sagittal alignment
to prevent PJF.
Surgically treated ASD patients (age ≥18 yrs; ≥5 levels fused, ≥1 year follow-up) enrolled into a prospective multi-center ASD database were propensity score matched (PSM) to control for risk factors for PJF. Patients evaluated for use of surgical implants to prevent PJF (IMPLANT) versus
no implant prophylaxis
(NONE), and categorized by the type of implant used (CEMENT, HOOK, TETHER). Postoperative sagittal alignment was evaluated for overcorrection of age-adjusted sagittal alignment
within sagittal parameters (ALIGN). Incidence of PJF was evaluated at minimum 1 year postop.
Six hundred twenty five of 834 eligible for study inclusion were evaluated. Following PSM to control for confounding variables, analysis demonstrated the incidence of PJF was lower for IMPLANT (n = 235; 10.6%) versus
NONE (n = 390: 20.3%; P
< 0.05). Use of transverse process hooks at the upper instrumented vertebra (HOOK; n = 115) had the lowest rate of PJF (7.0%) versus
NONE (20.3%; P
< 0.05). ALIGN (n = 246) had lower incidence of PJF than OVER (n = 379; 12.0% vs.
19.2%, respectively; P
< 0.05). The combination of ALIGN-IMPLANT further reduced PJF rates (n = 81; 9.9%), while OVER-NONE had the highest rate of PJF (n = 225; 24.2%; P
Propensity score matched analysis of 625 ASD patients demonstrated use of surgical implants alone to prevent PJF was less effective than combining implants with avoidance of sagittal overcorrection. Patients that received no PJF implant prophylaxis
and had sagittal overcorrection had the highest incidence of PJF.
Level of Evidence: 3