calcific myonecrosis

Calcific myonecrosis refers to a rare post-traumatic phenomenon. It characterized by the latent formation of a dystrophic calcified mass occurring almost exclusively in the lower limb (it has been occasionally reported at other sites).

Radiographic features

Plain film

Plain radiographs typically show a fusiform mass with peripherally oriented plaque-like amorphous calcifications. These are usually linear in orientation and sheetlike and may be present within the entire muscle or compartment, with mixed areas of radiolucency. Smooth bony erosions may be present with minimal periosteal reaction.

CT

Allows better anatomical visualization of calcifications.

May show a fusiform mass like region which often has a cystic lobulated component that sometimes erodes into bone, presumably because of a chronic pressure effect.

Fluid calcium levels may be seen representing communication between the necrotic muscle and the tendon sheath.

Associated reactive periostitis of the underlying bone may be present.

MRI

MRI shows a well-circumscribed mass. Describe signal characteristics include :

  • T1: homogeneous intermediate signal throughout the central fluid region 
  • T2: heterogeneous signal but the liquid center has a high signal
  • C+ (Gd): does not show enhancement after gadolinium administration
  • STIR: a subtle feathery periosteal bone reaction may be better appreciated on this sequence
  • gradient echo: a susceptibility artifact represented by blooming can be appreciated on the gradient echo images due to the calcium content

History and etymology

The condition was initially described by Gallie and Thompson in 1960.

See also

Siehe auch: