Calcific myonecrosis mimicking soft tissue sarcoma: A case report

Abstract

Calcific myonecrosis is a rare soft tissue condition. The first case was reported in 1960, however, the precise pathophysiology of calcific myonecrosis remains unclear. The disease was thought to arise from compartment syndrome within a confined space resulting in necrosis and fibrosis, subsequent repeated intralesional hemorrhage, mass enlargement and calcification. Several previous reports have described calcific myonecrosis, which include the formation of calcific myonecrosis after a prolonged period of post trauma. Notably, calcific myonecrosis has typically been described in the lower legs and characteristic imaging findings have been indicated. Furthermore, surgical intervention carries a high risk of complications. In the present case report 2 cases of calcific myonecrosis that occurred after a prolonged period of time following a traumatic event that impacted the lower leg were reported. CT images revealed disruption of calcified fascia and disease expansion into the outside of the fascia. Previous reports have implied that there is late focal enlargement of calcific myonecrosis following earlier enlargement, which may be caused by herniation through muscle fascia. However, no previous publications have focused on images for evidence of late local enlargement. To the best of our knowledge, this is the first report focusing on fascial herniation of calcific myonecrosis using images. Analysis of this feature using images may aid clinicians to differentiate calcific myonecrosis from malignancies.

Calcific Myonecrosis of the Leg: A Rare Entity

“…There was a slight male predominance (33 male and 7 female patients), as in the present case. The most common area of calcific myonecrosis was the anterior compartment of the leg followed by the lateral and deep posterior compartments; a total of 37 cases were reported in the leg [1,2,4,5,6,8,9,10,11,12,13,14,15,16,17,18,19,20,21,23,24,25,26,27], two cases in the forearm [3,22], and one case in the foot [7].…”

“…A closed fracture or trauma often associated to compartment syndrome are the most common causes of calcific myonecrosis [1,2,3,5,6,7,8,9,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,26,27]; in two papers describing 14 cases, data on previous trauma were not available [4,18]. Trauma may consist of a fracture (26 cases), strain or ligamentous injury (10 cases), snake bite (2 cases) [16,23], and gunshot lesion (2 cases) [25,27].…”

“…Trauma may consist of a fracture (26 cases), strain or ligamentous injury (10 cases), snake bite (2 cases) [16,23], and gunshot lesion (2 cases) [25,27]. A peroneal nerve injury was reported in nine cases [5,6,14,17,24,25], and a sciatic nerve injury in two cases [10,18]. Clinical presentation usually includes a painful soft tissue mass; occasionally, as in the present patient, the mass can be painless, or present with signs of infection [7,17].…”

“…First described more than 40 years ago by Gallie and Thomson [1], it is characterized by the replacement of muscle in one or more compartments with a fusiform mass or masses showing peripheral calcification and central liquefaction. It has been reported to develop primarily in the leg and has been attributed to trauma, such as a fracture accompanying ischemic symptoms and/or peripheral nerve injury [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27]. Although not well understood, it is postulated that these lesions most likely result from post-traumatic ischemia and cystic degeneration of the muscle [19].…”

Total knee arthroplasty in a patient with ipsilateral calcific myonecrosis

“…Calcific myonecrosis (CM) is a rare, post-traumatic soft tissue condition characterized by the formation of a slow-growing, dystrophic calcified mass. Such lesions, often occurring within the anterior compartment of the lower limb, are believed to arise from tissue ischemia and sensory deficits resulting from compartment syndrome; the compartment syndrome typically occurs many years prior to the development of the mass [1] , [2] . This very uncommon condition is relevant to orthopedists because it may mimic a malignant condition [2] and also because surgical intervention for CM is accompanied by a high risk of complications [3] .…”