Risk factors for predicting cement leakage in percutaneous vertebroplasty for spinal metastases

The study aimed to identify the risk factors of cement leakage following percutaneous vertebroplasty for spinal metastases. 230 consecutive patients with 530 vertebrae were retrospectively reviewed. Characteristics including age, primary cancer, location, pathological fracture, the integrity of the posterior wall, and the volume of bone cement were considered as potential risk factors. Cement leakage was evaluated by postoperative imaging examination and classified into three subtypes with different potential sequelae: spinal canal leakage, intravascular leakage around vertebrae, intradiscal and paravertebral leakage. Univariate and multivariate analyses were used to assess the risk factors. Leakage was detected in 185 vertebrae (34.9%), 18.3% for intradiscal and paravertebral, 13.2% for intravascular around vertebrae, and 7.0% for spinal canal. Multivariate analysis showed that incomplete posterior wall (P = 0.001) and breast cancer (P = 0.015) were strong predictive factors for spinal canal leakage, incomplete posterior wall (P = 0.024) was for intravascular leakage around vertebrae, thoracic (P = 0.010) and pathological fracture (P = 0.000) were for intradiscal and paravertebral leakage. Our findings suggest that cement leakage is common following percutaneous vertebroplasty for spinal metastases. The incomplete posterior wall is an unfavourable factor for intravascular leakage around vertebrae. Vertebrae with incomplete posterior wall and breast cancer metastases are more likely to develop spinal canal leakage.