Pseudoaneurysm after arthroscopic subacromial decompression and distal clavicle excision.

Arthroscopic shoulder surgery is considered a safe and effective method of treating a variety of shoulder pathologies and is associated with a low complication rate. The type and rate of complications can vary, depending on the procedure, positioning, surgical time, and anesthesia. Fortunately, neurovascular injuries occur infrequently. Numerous studies have described the proximity of neurovascular structures to portals placed in shoulder arthroscopy, in both the beach chair and the lateral decubitus positions. Accurate portal placement is important to avoid damage to adjacent neurovascular structures. Inaccurate placement of portals can lead to inadvertent damage to these structures and create more difficulty with visualization and angle of instrumentation, possibly compromising the success of the procedure. This article describes a 50-year-old man who underwent arthroscopic subacromial decompression and distal clavicle excision for persistent subacromial impingement and acromioclavicular arthritis. During postoperative follow-up, the patient had a small, bulging area located near the anterior portal site. Examination showed a well-healed anterior portal site with a small (approximately 2×2 cm), nontender, immobile mass located within the deep soft tissues just below the anterior portal incision. Ultrasound evaluation showed a pseudoaneurysm of a branch off the axillary artery. The patient underwent successful embolization of the pseudoaneurysm, with complete resolution of symptoms.