This 3½-year-old girl was referred with a provisional diagnosis of osteomyelitis of the right tibia. She had painless swelling over the upper, medial aspect of the right tibia lasting several months. On physical examination, the swelling was soft, nontender, and extended over 4 cm. Six months earlier, the skin in this area had been penetrated by a palm frond, which had been removed. There was no identifiable skin lesion at the injury site.
Frontal and lateral roentgenograms of the lower leg were obtained (Fig 1) and ultrasonography (Fig 2) of the same region was later performed.
Denouement and Discussion
Thorn-Induced Pseudotumor of the Tibia
Roentgenography showed a periosteal soft-tissue mass with secondary reactive periosteal thickening. The history of palm frond injury was strongly suggestive of soft tissue and periosteal response (pseudotumor) to an organic foreign body. This supposition was confirmed with ultrasound and operation. At surgery,
Kozlowski K, Glasson M, Wood BP. Radiological Case of the Month. Am J Dis Child. 1991;145(10):1159–1160. doi:10.1001/archpedi.1991.02160100091029