Morton’s interdigital neuroma: instructional review

[摘要] The term ‘Morton’s neuroma’ is in itself controversial. Histological examinations have shown that the histopathological features of resected ‘neuromata’ are not any different than those of biopsies from second/third intermetatarsal space nerves in feet with no pain. Only the dimension/width of the neuroma is different in that they are larger than that of a normal nerve.1 So does a ‘neuroma’ of the interdigital space really exist? It is important to mention that Morton himself described in 1876 a painful syndrome of the fourth metatarsophalangeal joint, rather than a nerve problem,2 whereas others before him had described a ‘painful clinical syndrome of the forefoot’.3 Thus, the widely used terminology of ‘Morton’s neuroma’ may represent an over-simplification of the clinical condition and may be misleading for doctors and patients. It is important for doctors who deal with this condition to realize that the problem is not a benign tumour of the nerve (as the terminology would imply), but a neuropathic pain in the forefoot that is associated with the interdigital nerve (most commonly the one between the third and fourth metatarsal heads), and to educate their patients accordingly. Furthermore, we have to appreciate the functional and biomechanical issues that may underlie the problem and the potential associated deformities and anatomical variations that produce plantar forefoot pain (metatarsalgia). As we will describe in the following paragraphs, ‘Morton’s neuroma’ is a painful forefoot syndrome, usually related to the third interdigital nerve, that is associated with overloading and altered pressure distribution in the foot because of deformity and/ or calf muscle tightness.

[学科分类] 神经科学

[关键词] interdigital nerve;metatarsalgia;Morton’s neuroma