Methotrexate osteopathy.

Methotrexate osteopathy is an uncommon complication of long-term oral maintenance therapy for childhood neoplasms, most commonly acute lymphocytic leukemia. It is characterized by severe lower extremity pain and by osteoporosis particularly involving the lower extremities and thick dense provisional zones of calcification and growth arrest lines resembling scurvy. Fractures may occur. The appearance must be distinguished from recurrent or metastatic disease.