Preliminary results of the effect of prophylactic vertebroplasty on the incidence of proximal junctional complications after posterior spinal fusion to the low thoracic spine

Study Design: Prospective cohort study. Objective: To evaluate, in adults undergoing posterior spinal fusions, 1) the effect of prophylactic vertebroplasty on the incidence of proximal junctional kyphosis (PJK) and proximal junctional failure (PJF), and 2) the difference in outcomes between those who did and did not develop PJK or PJF. Summary of Background Data: Proximal junctional kyphosis occurs in 20% to 39% of adults after posterior spinal fusions; a subset develops PJF. Methods: From 2005 through 2008, we treated 41 consecutive patients (40 years old or more) with spinal deformity with 2-level prophylactic vertebroplasty (at the upper instrumented vertebrae and the supra-adjacent vertebrae) during posterior spinal fusion. The 38 patients with 24 months' follow-up formed our study group. We measured patient outcomes with the Scoliosis Research Society-24 questionnaire, the Oswestry Disability Index, and the 12-item Short Form Survey. All patients completed each assessment preoperatively, and 89% or more did so postoperatively. We compared postoperative and final follow-up radiographs to identify the PJK incidence (ie, a PJK angle change of 10° or more), and analyzed the PJK, PJF, and non-PJK/PJF groups for outcome scores with Student t test and chisquare test (significance, p < .05). Results: Three patients (8%) developed PJK and 2 (5%) developed PJF, markedly lower incidences than those previously reported. At final follow-up, patients with PJK or PJF reported statistically significant lower pain and satisfaction Scoliosis Research Society-24 scores than did patients in the non-PJK/PJF group, but there were no significant differences in Scoliosis Research Society-24 mental health or function scores between groups. All patients had significant improved Oswestry Disability Index and 12-item Short Form Survey scores. Conclusions: Prophylactic vertebroplasty in long posterior spinal fusions for adult spinal deformity resulted in a low incidence of PJF and PJK, with only small differences in outcome scores between those who did and did not develop PJK and PJF.