An Intravertebral Pseudoaneurysm Formed after Infective Spondylitis

The surgical treatment of spondylitis involves potential risks, especially when dealing with infected tissues that may be fragile and susceptible to injury from surgical trauma and inflammation. In cases where spondylitis is not controlled even after the initial surgery, unexpected situations can arise if an unusual change in infected tissues around the spine is misinterpreted. The present case involves a 62-year-old who underwent laminectomy, debridement, and stabilization from T12 to L2 due to medically intractable spondylitis caused by methicillin-resistant Staphylococcus aureus. No major bleeding or vascular injury occurred during surgery. However, despite some improvement in pain and weakness, inflammation markers remained elevated and back pain recurred. A computed tomography (CT) scan taken 15 days after surgery showed a round-enhancing lesion inside the L1 vertebra. Although the primary imaging diagnosis suggested a loculated abscess, a round-enhancing lesion raised suspicion of an unusual pseudoaneurysm. A CT angiography confirmed a pseudoaneurysm from the L1 segmental artery, successfully treated with endovascular embolization. After embolization, the patient’s back pain improved, and inflammation markers further decreased with oral antibiotics. This case highlights the possibility of a pseudoaneurysm occurring in cases of spondylitis, emphasizing the importance of considering this entity in the differential diagnosis to ensure proper treatment.