PMMA cementoplasty in symptomatic metastatic lesions of the S1 vertebral body

We describe a lateral transiliac direct puncture approach to the S1 vertebr al body for polymethylmethacrylate (PMMA) cementoplasty of painful metastat ic lesions. This approach was performed using a 15-cm-long trocar needle wi th 3-mm outer diameter, introduced under general anesthesia and fluoroscopi c control. A lateral projection was used to center the needle just in front of the spinal canal and subjacent to the superior plate of the S1 vertebra l body. Needle progression was controlled using anteroposterior and lateral fluoroscopic projections alternately with a needle course parallel to an a xial plane, avoiding conflict with the S1 foramen. After needle tip placeme nt in the center of the S1 vertebral body, diluted PMMA with a setting time of 8 min was delivered. Ipsilateral lesions of the lateral sacral compartm ent were filled with the same needle by stepwise withdrawal and continuous PMMA injection.