Hyperbaric oxygen corrects sacral plexopathy due to osteoradionecrosis appearing 15 years after pelvic irradiation.

In 1982, a 55-year-old woman was treated by total cystectomy and adjuvant radiotherapy/chemotherapy for a leiomyosarcoma of the bladder. Fifteen years later she presented with symptoms and signs of sacral plexopathy. Investigations revealed osteoradionecrosis of the sacrum. Hyperbaric oxygen therapy (HBO2) was instituted and progressive resolution of the neurological complaints followed. HBO2 should be considered when managing late-onset sequelae in previously irradiated patients.