Long term complication of compartment syndrome in anterior compartment of lower limb “Calcific myonecrosis”

– Rare post-traumatic entity characterized by latent formation of a dystrophic calcified mass occurring almost exclusively in anterior compartment of lower leg.

Initial compartment syndrome resulting in necrosis and fibrosis
Over time, repeated intralesional hemorrhage causes the mass to enlarge and calcify

Slowly enlarging, usually painful soft-tissue mass in the anterior compartment of the lower limb.

Radiograph, CT
– Fusiform mass with peripherally oriented plaque-like amorphous calcifications within the entire muscle or compartment
– Smooth bony erosion, reactive periosteitis
MRI
– T1WI : iso-/high SI (subacute hemorrhage, proteinaceous content)
– T2WI : high SI (cystic change), low SI (calcium salts, paramagnetic breakdown products of hemorrhage)
– Low SI outer rim (calcification and fibrosis)
– No enhancement