Delayed chylous fluid leakage at the surgical site following thoracic corpectomy via a lateral extracavitary approach: illustrative case

BACKGROUND Chylous fluid leakage following spinal surgery is a rare and potentially difficult-to-manage complication that can lead to wound complications, pain, or nutritional deficiencies. Although the thoracic duct is localized near the thoracic spine, reports of thoracic duct injuries secondary to posterior thoracic spine surgery are rare. OBSERVATIONS The authors present the case of a 57-year-old male with a known history of metastatic renal cell carcinoma to the thoracic spine who had undergone a thoracolumbar fusion with thoracic corpectomy and presented with concern for a chyle leak almost a year after his surgery. The patient had a complicated oncological history and underwent decompression and fusion to treat his significant thoracic metastatic disease. A year later, he presented with back pain and a significant fluid collection at the surgical site, which was drained and found to be consistent with chyle. The patient was treated conservatively, and imaging of the thoracic duct a few months later demonstrated no direct injury, likely indicating either transient injury or potential obstruction of the thoracic duct from metastatic disease. LESSONS This case demonstrates a rare, potential complication when treating extensive thoracic metastatic disease as well as the workup and potential treatments when facing thoracic duct injury. https://thejns.org/doi/10.3171/CASE24280