Asymptomatic Azygos Vein Cement Embolism: A Potential Risk of Cement Injection via Cannulated Screw: A case report

Abstract

Objective: Vertebroplasty is a method that stabilizes the fracture and relieves pain by injecting cement into the vertebral body that has lost its height for some reason. Cement injection can also be done through kyphoplasty and cannulated screw. During the injection, protrusion of the cementum from the corpus is a complication that must be avoided in this procedure. Cement extending out of the corpus may cause pulmonary cement embolism (PCE) via the azygos vein.

Case: A 76-year-old female patient was admitted to our clinic with the complaint of low back pain that had been going on for one year. The patient, who did not have motor or sensory deficits in the examination, described neurogenic claudication at 200 meters as well as sensitivity in the lumbar region. An osteoporotic collapse fracture in the L1 vertebra was detected in the patient's imaging.  Transpedicular fixation, decompression, and cement-augmented pedicle screw were applied to the patient. After the operation, vena azygos cement embolism was detected in the thoracolumbar computed tomography (CT) scan conducted for follow-up. Although detailed tests were performed for pulmonary embolism (PCE), no findings were detected in the asymptomatic patient. During the follow-up examination after discharge, the patient did not report any respiratory complaints, pain in the lumbar region, or neurogenic claudication complaints.

Conclusion: PCE may develop after cement leakage into the azygos vein during cement injection. Although most PCEs remain asymptomatic, sometimes serious or even fatal sequelae have been reported. Cement overflows not reflected in fluoroscopy during the procedure can be detected by post-procedure imaging, and patients can be protected from serious complications.