For a year and a half, a 10-year-old boy in Mumbai had a swelling on the inside of his right ankle that would not go away. It measured roughly 8 by 4 centimeters, sat just below the medial malleolus, and hurt more when he was active. The skin over it was normal. No scar, no draining opening, no sign of infection. He and his parents remembered minor falls during play but no specific puncture wound.
X-rays were normal. MRI found inflammation but not its cause. It took an ultrasound to reveal what had been sitting in his ankle the whole time: a fragment of wood 1.7 centimeters long and 3 millimeters wide.
