To determine whether two adults with stress fractures receiving low weekly doses of methotrexate had methotrexate osteopathy.
Two adult patients developed features consistent with methotrexate osteopathy while receiving low weekly doses of methotrexate.
Iliac crest biopsy samples were taken and bone histomorphometry carried out.
Symptoms resolved when the methotrexate was discontinued. Bone histology showed changes consistent with osteoblast inhibition by methotrexate.
When given in low doses for prolonged periods, methotrexate may have adverse effects on bone, particularly in post-menopausal women.