PMMA cementoplasty in symptomatic metastatic lesions of the S1 vertebral body

We describe a lateral transiliac direct puncture approach to the S1 vertebral body for polymethylmethacrylate (PMMA) cementoplasty of painful metastatic lesions. This approach was performed using a 15-cm-long trocar needle with 3-mm outer diameter, introduced under general anesthesia and fluoroscopic 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 vertebral body. Needle progression was controlled using anteroposterior and lateral fluoroscopic projections alternately with a needle course parallel to an axial plane, avoiding conflict with the S1 foramen. After needle tip placement 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 compartment were filled with the same needle by stepwise withdrawal and continuous PMMA injection.