A "harness" distribution pattern on pediatric Ga-67 scintigraphy

An 18-month-old girl was evaluated at our institution for a limp and discomfort on movement of her right lower limb. Because joint or bone infection was suspected, Tc-99m MDP scintigraphy was performed. A mild relative decrease in soft-tissue uptake in the right lower limb was noted, in keeping with disuse. Correlative Ga-67 imaging performed 6 days later showed unexpected abnormal avid uptake in a harness type of distribution over the upper anterior and lateral thorax. No respiratory symptoms were evident, and no pulmonary, pleural, or soft-tissue abnormality was detected clinically or radiologically. The patient's clinical syndrome resolved with treatment of her symptoms. In this case, the abnormal tracer distribution was thought to correspond with the anatomic distribution of the serratus anterior muscle and represents an interesting and extreme variation in the pattern of nonpathologic muscular tracer activity that is sometimes noted in children.