Osteopathic Potential of Methotrexate: Medial Tibial Stress Syndrome.

Abstract

©2016 Turkish League Against Rheumatism. All rights reserved. Methotrexate (MTX) is a folic acid antagonist commonly used for the treatment of malignancies, autoimmune diseases, and chronic inflammatory conditions like rheumatoid arthritis and psoriatic arthritis.1,2 Methotrexate osteopathy is one of the side effects of the drug when used in high doses and is characterized by bone pain, osteopenia, and insufficiency fractures.1 This spectrum of MTX osteopathy was previously studied in patients on low-to intermediate doses and the results varied.1,3-5 Shin splints or medial tibial stress syndrome (MTSS) is caused in response to the chronic repetitive stress on the posteromedial border of the tibia and seen mostly in athletes and military personnel.6 To our knowledge, there are only a few reports in literature describing MTSS in patients with rheumatoid arthritis and psoriatic arthritis under MTX treatment.3,6,7 In this article, we report a 59-year-old female patient with a three-year history of rheumatoid arthritis who presented with severe pain and swelling of the tibia. She described the pain on the anterior and medial aspect of the lower leg not relieved by rest. She had no predisposing history of physical activity. She was under MTX (10 mg/week) and low dose prednisolone therapy. On laboratory analysis, C-reactive protein value was 0.20 mg/dL, sedimentation rate was 29 mm/hour, and dual energy X-ray absorptiometry showed osteopenia. Extremity X-ray was normal. Magnetic resonance imaging (MRI) revealed periosteal edema as hyperintensity on fat-saturated T2-weighted images, adjacent to the outer surface of the medial cortex of mid-to-distal tibial diaphysis (Figure 1). Regression of the patient’s complaints in one month after lowering the dosage of MTX endorsed the radiological diagnosis.