Predictors of Kyphoplasty Failures Requiring Surgical Stabilization in Patients With Cancer With Pathological Vertebral Body Fractures.
Academic Article
Overview
abstract
BACKGROUND AND OBJECTIVES: Pathological vertebral compression fractures (VCFs) cause significant morbidity in the population with cancer. Although both stabilization of fractures with kyphoplasty and pedicle screw fixation can alleviate pain and prevent neurological compromise in select patients, there are no criteria demarcating which patients can be treated with kyphoplasty alone vs pedicle screw fixation, particularly for those with intermediate spinal instability. The objective of this study was to identify predictors of kyphoplasty failure requiring subsequent surgical stabilization in patients with metastatic thoracolumbar VCFs. METHODS: Patients who underwent single or 2 level kyphoplasty for pathological VCFs between 2015 and 2020 were included in a retrospective analysis at a tertiary cancer center. The primary outcome measure was kyphoplasty failure, defined as return to the operating room for pedicle screw fixation. Hazard ratios (HR) were estimated in the competing risks setting. Thresholds for variables were identified where possible. RESULTS: Forty-two of 445 patients (9.8%) failed kyphoplasty, with an average time to failure of 318 days and a 5-year cumulative incidence of 10.3% (95% CI: 7.5%-13.6%). We found focal kyphotic angle (HR 1.09, 95% CI: 1.05-1.12, P < .0001), Spinal instability neoplastic score (HR 1.16, 95% CI: 1.05-1.28, P = .03), spinal canal compromise (HR 1.05, 95% CI: 1.03-1.07, P < .0001), and posterior element involvement (HR 1.93, 95% CI: 1.03-5.63, P = .04) to be significantly associated with increased risk of kyphoplasty failure even after mutual adjustment in the multivariable setting. There were no significant associations between kyphoplasty failure and sex, age at kyphoplasty, anatomic location, or quality of bone lesion. CONCLUSION: Kyphoplasty failure in metastatic VCFs is associated with specific radiographic markers of spinal instability. Patients with spinal instability neoplastic score ≥11, posterior-element involvement, canal compromise, and significant kyphosis may benefit from up-front surgical stabilization with pedicle screws, particularly for patients with anticipated long-term survival.
