Morton Disease

Abstract

Morton disease is an entrapment neuropathy of the common plantar digital nerves between the metatarsal head and neck. Entrapment is exacerbated by the wearing of narrow-width shoes or warped soles. It is common in Europe and the United States where shoes are worn throughout the day; it is less common in Japan where street shoes are not worn inside. Pain or numbness involving the focal area of the plantar aspect of the foot and both toes next to the entrapment site are readily recognized symptoms leading to a diagnosis of Morton disease. They are elicited upon loading at the entrapment site by walking, standing, or exercising. A Tinel-like sign in the affected area is also diagnostically informative. The most reliable diagnostic method is symptom improvement upon blocking the nerve at the entrapment site. Radiological study may reveal the presence of occupying lesions or Morton neuroma. Conservative therapy, toe-joint stretching, physiotherapy, wider shoes, metatarsal pads, and nerve blocks may reduce symptom severity. The results of neurolysis or neurectomy tend to be satisfactory although it may be difficult to obtain complete pain relief. Because re-operation may not be successful, the value of surgical retreatment must be carefully considered.