Muscular injury in a child diagnosed by 99mTc-MDP bone scan.

An 11-year-old boy had bone scanning to rule out an osseous lesion of the right arm. He presented progressive pain and hard swelling of the right arm. His past medical history and general physical examination were unremarkable. He trained for karate. The scan demonstrated considerable muscular uptake in both arms. CPK and CPK MB levels were both abnormally high, suggesting muscle injury. After a 10-day rest period the bone scan returned to normal.