Case report 241. Post-traumatic pseudoaneurysm of the axillary artery producing pseudotumor of the humerus

Differential Diagnosis of Thoracoacromial Artery Pseudoaneurysm from Shoulder Inflammatory Pseudotumor: A Case Report

Diagnosing shoulder tumors is a challenge because the joint is very complex, and a static examination can misdiagnose some tumors. However, we found that a pseudoaneurysm provides a differential diagnosis of a tumor, and to that end, we present a case that mimics shoulder infection. The patient was an 80-year-old female who had a history of coronary artery disease and end-stage renal disease under regular hemodialysis and complained of right shoulder swelling and progression. A magnetic resonance imaging (MRI) scan revealed an abscess, inflammatory pseudotumor (IPT), and osteomyelitis of the humerus. Computed tomography (CT)-guided pigtail drainage was performed twice without significant improvement. An angiogram revealed a right shoulder pseudoaneurysm fed by the acromial branch of the thoracoacromial artery. After endovascular coiling, the patient was discharged and outpatient follow-up was arranged. If aspiration of the abscess leads to only mild improvement in shoulder swelling, further evaluation should be arranged. An angiogram examination is a good method for diagnosing and designing operations, and endovascular treatment is good for preventing injury to the muscle, tendon, nerve, or blood vessels.

Arterial pseudoaneurysms of the shoulder mimicking other entities: utilization of pulsation artifact on musculoskeletal MR for accurate diagnosis in 2 cases

We present two cases of pseudoaneurysm (PSA) about the shoulder mimicking more common clinical entities-soft tissue neoplasm and septic arthritis-for which biopsy of the mass and joint aspiration were requested respectively. We review the imaging findings of PSA with emphasis on findings in musculoskeletal protocol MRI, including the identification of pulsation artifact in both cases, which was critical to establishing the correct diagnosis. In the proper clinical setting, with imaging findings demonstrating a complex mass or fluid collection, MR images should be scrutinized for the presence of pulsation artifact, which can help diagnose a high-flow vascular lesion and avoid a potentially harmful invasive procedure such as biopsy.

Pseudoaneurysms Occurring as a Result of Fractures Giving Rise to the Appearance of Pseudotumors: A Short Series

Pseudoaneurysms are focal enlargements of the vascular lumen due to partial or complete disruption of the arterial wall. These are an uncommon complication of fractures. The presence of a pseudoaneurysm adjacent to a fracture fragment can cause a pressure effect. This pressure not only impairs fracture healing but sometimes can erode the adjacent bone, producing the appearance of a pseudotumor. We present two such cases and discuss the management of these patients.

Pseudoaneurysm after interscalene block for a rotator cuff repair

We present a case of a 68-year-old female patient who had an interscalene nerve block (ISB) complicated by compression of her brachial plexus by a pseudoaneurysm. The complication occurred after the patient received an ISB as anesthesia for an outpatient shoulder procedure. Review of this complication should alert surgeons to consider this diagnosis as a possibility in patients with postoperative pain and/or neurologic compromise after receiving an ISB.