Incidence of Cement Leakage and Potential Risk Factors in Surgery for Spinal Metastasis: A Systematic Review and Meta-Analysis.

Objectives: The current meta-analysis was performed to gather available evidence regarding the incidence and risk factors of cement leakage (CL) in patients undergoing surgical procedures for spinal metastasis.

Methods: Two authors independently searched the PubMed, Embase, and CENTRAL databases. Clinical studies reporting the incidence or risk factors of CL were included for analysis. The primary outcome analyzed was the incidence of various types of CL. Random-effects or fixed-effects single-proportion meta-analyses were conducted to pool the available evidence, based on the heterogeneity test. Subgroup analyses were conducted based on surgical procedures (percutaneous vertebroplasty, percutaneous kyphoplasty, and others). Risk factors of CL were synthesized narratively to identify the most commonly accepted factors.

Results: A total of 26 studies, involving 2551 patients, were included. The number of operated spine segments was reported in 23 studies, accounting for 4101 vertebrae. The pooled incidences of general, intradiscal, paravertebral, spinal canal, and intravascular CLs were 0.18 (95% confidence interval [CI], 0.11-0.28), 0.14 (95% CI, 0.08-0.21), 0.13 (95% CI, 0.06-0.21), 0.11 (95% CI, 0.05-0.19), and 0.12 (95% CI, 0.08-0.17), respectively. Subgroup analyses revealed significantly different incidences of general CL (0.37 vs. 0.06 vs. 0.09, P < 0.01), intradiscal CL (0.22 vs. 0.06 vs. 0.12, P < 0.01), paravertebral CL (0.25 vs. 0.03 vs. 0.06, P < 0.01), and vascular CL (0.14 vs. 0.03 vs. 0.15, P < 0.01) among the three groups. Posterior wall disruption, pathologic fracture, and the number of treated vertebral levels were the most commonly identified independent risk factors for general CL. Posterior wall disruption was determined as a common significant risk factor for spinal canal CL.

Conclusions: This review provides insights into the incidence and risk factors associated with CL in surgical procedures for spinal metastasis. Understanding these risk factors can contribute to the development of tailored strategies aimed at minimizing CL occurrence and optimizing surgical outcomes for patients undergoing spinal metastatic surgery.