Calcific myonecrosis: a unique presentation in the upper extremity

Abstract

Calcific myonecrosis is a rare and latent condition characterized by a dystrophic calcified lesion that can present 10-64 years following initial trauma. Of the 25 cases documented in English world literature, all have occurred in the lower extremity exclusively. We report a case of a 60-year-old man with a painless enlarging left forearm mass that was subsequently diagnosed as calcific myonecrosis. Awareness of this lesion arising outside of the lower extremity is important to avoid unnecessary surgical intervention and patient reassurance.

Calcific Myonecrosis of the Upper Extremity: Case Report

“…Occasionally, the mass will be asymptomatic. 3,[5][6][7] The initial injury is usually a crush, fracture, or blunt trauma that caused vascular compromise or an untreated compartment syndrome 10 to 64 years before the presentation of the mass (average, 51 y after injury). 2,4 There is one report of calcific myonecrosis in a patient with a history of juvenile dermatomyositis and no history of trauma.…”

“…Pathology reports from biopsied specimens reveal a densely fibrotic, calcified mass with the outer portion composed of hypocellular fibrous tissue and focal hemosiderin-laden macrophages. 3,9,32 The interior reveals necrotic tissue with amorphous debris composed of cholesterol crystals, fibrin, and organizing thrombus 9 appearing grossly as a thick reddish-brown liquid or paste. 2,3,5,6,32 Calcific myonecrosis can be confidently diagnosed on radiographic and MRI studies due to its unique imaging characteristics.…”

“…1 More than 50 cases of calcific myonecrosis have been reported, and all but one have occurred in the lower extremity. Larson and colleagues, 3 in 2004, reported a case of calcific myonecrosis in the forearm. We report an additional case of calcific myonecrosis in the upper extremity.…”

Orthopaedic Case of the Month: Painful Lower-leg Mass in a 76-year-old Man

“…The mean age of patients at presentation is 53 years (range, 34-87 years), and the mean interval between injury and diagnosis is 37 years (range, 5-64 years) [1-3, 5-21, 23, 24, 26-28, 30-33]. The lower limbs are involved in most cases although there is a report of upper extremity involvement [15]. The anterolateral compartment of the lower leg is the area most commonly affected [1].…”

MRI of Muscle Injuries

“…Most reported cases have occurred in the anterior and lateral compartments of the lower leg, with only single cases reported in the foot and forearm (Holobinko et al 2003;Larson et al 2004). This entity most commonly occurs due to compartment syndrome post fracture of the tibia or femur and more rarely after neurovascular injury (Early et al 1994;Milisano and Hunter 1992;Renwick et al 1994;Viau et al 1993).…”