CALCIFIC MYONECROSIS - A LATE SEQUELA TO COMPARTMENT SYNDROME OF THE LEG

The clinicopathologic features of calcific myonecrosis are presented f rom results of an examination of 3 cases of this rare syndrome and rev iew of the literature, Calcific myonecrosis is a painful, expansile, c alcified mass that develops in muscle several decades after lower extr emity trauma that typically has been associated with vascular injury, Plain radiographs show a well-defined and heavily calcified mass repla cing the leg musculature. The calcifications are present in a thin, li near pattern and are organized around the periphery of the lesion, Smo oth erosion of the adjacent bone may be present, whereas magnetic reso nance imaging shows a heterogeneous signal with enhancement limited to the periphery of the mass, Pathologic features consist of a centrally cystic mass arising in muscle filled with friable, tan to dark red, s oft debris, The cyst walls are firm and fibrous and contain many needl e-like, elongated, calcified shards of necrotic tissue composed of hyp ocellular fibrous tissue with focal aggregates of hemosiderin-laden ma crophages. The cyst contents are composed of necrotic skeletal muscle and acellular amorphous debris containing many cholesterol crystals, f ibrin, and recent hemorrhage, including focal aggregates of organizing thrombus, The pathologic findings suggest that calcific myonecrosis m ight expand with time by virtue of recurrent intralesional hemorrhage into a chronic calcified mass that eventually becomes symptomatic, Sur gical intervention is associated with a high rate of complication, par ticularly in cases in which intralesional procedures have been done.