SUPRAMALLEOLAR FATIGUE FRACTURES OF THE TIBIA

Objective. The objective of this paper is to describe fatigue fracture s in the supramalleolar area of the tibia. The spectrum of imaging fin dings in 14 cases is presented, with emphasis on plain film radiograph ic findings. Design and patients. Fourteen patients with fatigue fract ures in the supramalleolar area of the distal tibia were seen in a 6-y ear period. The 13 men and 1 woman had an age range from 14 to 64 year s (mean 30 years). These patients had no underlying conditions that wo uld predispose them to fractures. Sequential plain film radiographs an d other special imaging studies (technetium-99m scans and computed tom ography) were retrospectively reviewed. Results and conclusions. Initi al plain film radiographs showed a horizontal linear band of increased density in only 2 cases, a subtle cortical bulge in 5 cases, a focal ''graying'' of the cortex in 2 cases, a single layer peri osteal react ion in 1 case, and no abnormality in the final 4 cases. Technetium-99m scans were done in 11 cases and showed focal areas of increased uptak e in all 11. These areas of increased uptake were vertically orientate d in 10. One patient had computed tomography showing cortical thickeni ng around a linear lucency. The spectrum of imaging findings is simila r to that seen in fatigue fractures in more common locations. Supramal leolar fatigue fractures should be suspected in patients who have pain in the distal tibia even when initial plain film radiographs are norm al. When initial radiographs are normal, technetium-99m scans can conf irm the diagnosis.