The anterior part of the foot is formed by 5 bones called metatarsals, which in their final end articulate with each of the fingers, these metatarsals are tied together by intermetatarsal ligaments that bind them tightly to each other preventing them from separating from each other when we support the weight. Between the metatarsals travel the nerves that will give sensitivity to the fingers. When for some reason the nerve is trapped by the intermetatarsal ligament, the nerve fails to function properly, and a tumor of the nerve can be produced due to the constant irritation to which it is subjected.
There are multiple circumstances that can favor the entrapment of the nerve by the ligament such as: use of narrow-toed or high-heeled shoes that would crush one metatarsal with another, facilitating compression of the nerve that travels between them. The existence of a bursitis or a cyst between two metatarsals, which, when occupying the space through which the nerve travels, crushes it against the ligament. This disease occurs more frequently in middle-aged women.
The nerves that are affected most frequently are those that go between the 2nd and 3rd metatarsal and between the 3rd and 4th. They produce intense pain in the area of compression, the pain extends to the fingers corresponding to the compressed nerve (usually 2nd, 3rd and 4th). It can also be accompanied by a lack of sensitivity (hypesthesia) and tingling (paresthesia) in the affected fingers. The pain gets worse when you press on the area and it improves when you take off your shoes and massage your foot.
The conservative treatment is aimed at reducing the pressure that occurs between the metatarsals, this is achieved by using proper footwear, avoiding obesity and using discharge templates. Pain will also be treated with anti-inflammatories and analgesics, in some cases infiltrations with corticosteroids may be performed. Surgery is reserved for cases that do not respond well to conventional treatment, and this is intended to free the nerve from any structure that is compressing it (bursitis or synovial cyst), and in cases in which the constant irritation of the nerve a Given the appearance of a tumor that surrounds the nerve, with surgery it is attempted to carefully remove this tumor.