For four months, a 44-year-old woman watched a lump in her right groin get bigger. It ached when she exercised or stood for long periods, popped into view when she got up and slipped back when she lay flat. That is textbook behavior for an inguinal hernia, but the lump turned out to be something else.
Surgeons at Redcliffe Hospital in Queensland, Australia, traced the swelling to the canal of Nuck, a tiny passage in female anatomy that is supposed to seal shut in the first year of life. Hers had stayed open and filled with fluid, forming what doctors call a hydrocele of the canal of Nuck. The team described the case in the Journal of Surgical Case Reports in January 2026, calling it "a rare but important differential for a woman with a groin lump."
