A rare case report of acquired rubber band syndrome due to an unnoticed rubber band on a baby's ankle.

We report a case of a 7-month-old girl who presented with 2 months history of redness and swelling syndromes around the left ankle. The local hospital diagnosis of left ankle soft tissue infection and gave antibiotic treatment. However, her symptoms were failed respond to the antibiotic treatment and suggested to transfer to our hospital. We gave this girl a detailed physical examination, when opening the ankle crease a hidden rubber band was found and the surrounding soft tissues were lacerated. As a result, the child was taken to surgery to remove the band and repair the lacerated structures and her postoperative recovery was well. A rubber band worn for decorative purpose or accidently by the child is sometimes missed by the parents and remains long unnoticed. For the clinical features of a linear constricting scar around the wrist or ankle in the presence of a swollen syndrome, it should always alert the clinician to the possibility of a forgotten band around the joints. This appears to be the first case of acquired rubber band syndrome reported occurred on children's ankle.