Pseudomalignant myositis ossificans in children. Description of a case and review of the literature.

: The authors report a rare case of pseudomalignant myositis ossificans occurring during childhood. A female aged 10 years with no previous history of trauma came to their observation with findings of pain and progressive swelling in the gluteal region. The severity of the clinical findings and the absence of characteristic ossification in the x-rays obtained at the onset of the disease suggested that neoplastic pathology be excluded. Diagnosis (bone scan, CT scan, MRI, angiography, biopsy) and the progression of the disease, until its complete clinical resolution, are discussed in light of a review of the literature (44 cases of pseudomalignant myositis ossificans during pediatric age). All of the elements that may be of help in diagnosis and capable of avoiding surgical procedures that are either untimely or improper are emphasized.