Risk factor analysis of pulmonary cement embolism during percutaneous vertebroplasty or kyphoplasty for osteoporotic vertebral compression fractures.

Objective: The purpose of this research is to evaluate the risk factors and incidence of pulmonary cement embolism (PCE) during percutaneous vertebroplasty (PVP) or kyphoplasty (PKP) for osteoporotic vertebral compression fractures (OVCFs) based on postoperative computed tomography (CT).

Methods: A total of 2344 patients who underwent PVP or PKP due to OVCFs in our spine center were analyzed retrospectively. According to the detection of postoperative pulmonary CT, the patients were divided into two groups: pulmonary cement embolism group (PCE group) and non-pulmonary cement embolism group (NPCE group). Demographic data in both groups were compared using the χ test for qualitative data and the unpaired t test for quantitative data. Multiple logistic regression analysis was carried out to identify risk factors that were significantly related to the PCE resulting from cement leakage.

Results: PCE was found in 34 patients (1.9% 34/1782) with pulmonary CT examination after operation. There was no statistically significant difference in the parameters such as age, gender, body mass index (BMI), and cement volume in the two groups. Patients with three or more involved vertebrae had a significantly increased risk to suffer from PCE than those with one involved vertebra (p=0.046 OR 2.412 [95% CI 1.017-5.722]). Patients who suffered thoracic fracture had a significantly increased risk to suffer from PCE than those who suffered thoracolumbar fracture (p=0.001 OR 0.241 [95% CI 0.105-0.550]). And significantly increased PCE risk also was observed in thoracic fracture compared with lumbar fracture patients (p=0.028 OR 0.094 [95% CI 0.114-0.779]). The risk of PCE within 2 weeks after fracture was significantly higher than that after 2 weeks of fracture (p=0.000 OR 0.178 [95% CI 0.074-0.429]). Patients who underwent PVP surgery had a significantly increased PCE risk than those who underwent PKP surgery (p=0.001 OR 0.187 [95% CI 0.069-0.509]).

Conclusion: The real incidence of PCE is underestimated due to the lack of routine postoperative pulmonary imaging examination. The number of involved vertebrae, fracture location, operation timing, and operation methods are independent risk factors for PCE.