MR imaging of the forefoot: Morton neuroma and differential diagnoses.

Magnetic resonance (MR) imaging of Morton neuromas is highly accurate. Morton neuromas are more conspicuous when the patient is prone positioned and the foot is plantar flexed than in the supine position with the toes pointing upward. MR imaging of Morton neuromas has a large influence on the diagnostic thinking and treatment plan of orthopedic foot surgeons. The most common differential diagnoses include intermetatarsal bursitis, stress fractures, and stress reactions. Some diagnoses (nodules associated with rheumatoid arthritis, synovial cyst, soft tissue chondroma, and plantar fibromatosis) are rare and can be diagnosed with histologic correlation only.