A morton's neuroma (or an "inter-digital" neuroma) is found between the toes of the foot, most commonly the third and fourth toes. It can also occur between the metatarsal bones (the long bones in the forefoot). It is basically an entrapped nerve, which becomes inflamed due to constant irritation from the surrounding bony structures.
The source of this pain is an enlargment of the sheath of an intermetatarsal nerve in the foot. This usually occurs in the third intermetatarsal space, the space between the third and fourth toes and metatarsals. It occurs here, at the site third intermetatarsal nerve, since this intermetatarsal nerve is the thickest being comprised of the joining of two different nerves. It also may occur in the other intermetatarsal areas, with the second interspace being the next most common location.
The primary symptoms include sharp, shooting pain, numbness or paresthesia in the forefoot and extending distally into the toes, typically in the region of the third and fourth toes. Symptoms are aggravated with narrow toe box shoes or those with high heels. There is usually a reduction of symptoms when walking barefoot or wearing shoes with an appropriately wide toe box. Symptoms are also aggravated with shoes that are tied too tight.
The diagnosis of interdigital neuroma is usually made by physical examination and review of the patient's medical history.MRI ad High Definition Ultrasound examination may be useful to confirm the diagnoses however they may still not be 100% reliable. The commonest reason for this is de to natural substances present in between the metatarsal heads and between the fat pad and the intermetatarsal ligament. These natural substances i.e. bursa, fat, capsular thickening and even bony growths, can all be a factor in the impingement process and may need to be surgically cleared.
Non Surgical Treatment
Ice therapy and anti-inflammatory medications or supplements. If conservative care measures fail to resolve your problem, some foot care providers may recommend a cortisone injection around your involved nerve to help reduce your swelling and inflammation. Concentrated alcohol injections around your affected nerve have also shown good results and should be considered before undergoing neurectomy, a surgical procedure to remove the enlarged, traumatized portion of your involved nerve.
If your pain continues despite several months of conservative treatment, your doctor may recommend surgery to remove the neuroma or to widen the space through which the affected nerve travels. These types of surgery often are done under local anesthesia. If your doctor removes a portion of the affected nerve along with the neuroma, you may develop permanent numbness between the toes.