Social media solves a medical riddle

This foreign body was removed from a non-healing abdominal wall incision in an elderly lady with many comorbidities and previous operations. It was a rigid plastic tube which was 7 cm long and 2-3 mm in diameter. There were four transverse grooves at either end.

Physicians caring for her were unable to identify it. One of them emailed me the photos and asked for help. I didn't know what was, but I knew where to look for the answer.

I tried a Google image search, but the brownish discoloration of the object was interpreted as wood by the algorithm. None of the many images on Google resembled the foreign body.