Some sources claim that entrapment of the plantar nerve because of compression between the metatarsal heads, as originally proposed by Morton, is highly unlikely, because the plantar nerve is on the plantar side of the transverse metatarsal ligament and thus does not come in contact with the metatarsal heads. It is more likely that the transverse metatarsal ligament is the cause of the entrapment. Despite the name, the condition was first correctly described by a chiropodist named Durlacher, and although it is labeled a "neuroma", many sources do not consider it a true tumor, but rather a perineural fibroma (fibrous tissue formation around nerve tissue).
The cause of this problem is often due to impingement of the plantar nerve fibres between the metatarsal heads and the intermetatarsal ligament. It is entirely a biomechanical phenomenon. Differential diagnoses include stress fracture, capsulitis, bursitis or ligament injury at the metatarsal-phalangeal joint, a tendon sheath ganglion, foreign-body reaction and nerve-sheath tumour.
Symptoms include tingling in the space between the third and fourth toes, toe cramping, a sharp, shooting, or burning pain in the ball of the foot and sometimes toes, pain that increases when wearing shoes or pressing on the area, pain that gets worse over time. In rare cases, nerve pain occurs in the space between the second and third toes. This is not a common form of Morton neuroma, but treatment is similar.
A GP (general practitioner, primary care physician) or a podiatrist (foot specialist doctor) will ask the patient to describe the pain as well as its intensity, when symptoms started, what types of shoes are worn, as well as some questions about their job, lifestyle and hobbies. The doctor will then examine the foot and try to locate the affected nerve. This may involve attempting to reproduce symptoms by manipulating the foot. In order to get a detailed image of the inside of the food, one of the following scans may be ordered. X-ray, this is a type of high-energy radiation. In low doses they are used to diagnose diseases and condition by making pictures of the inside of the body. In higher doses they are used to treat cancer. This procedure is non-invasive and painless. Ultrasound scan, high frequency sound waves are pointed at a specific part of the body, which in this case is the foot. The ultrasound waves bounce of tissues; their echoes are then converted into a picture, called a sonogram. This allows the doctor to get an inside view of the foot. This procedure is non-invasive and painless. MRI (magnetic resonance imagining) a device that uses a magnetic field and radio waves to create detailed images of the body. Unlike CT scanning or general x-ray studies, no ionizing radiation is involved with an MRI. This procedure is non-invasive and painless. The doctor will have to rule out other conditions which may have similar symptoms, including capsulitis, bursitis, or Freiberg's disease.
Non Surgical Treatment
Pain is the main reason that you seek treatment for a neuroma. Analgesics may help. Inflammation it best eased via ice therapy and techniques or exercises that deload the inflammed structures. Anti-inflammatory medications may help. Your physiotherapist will use an array of treatment tools to reduce your pain and inflammation. These include: ice, electrotherapy, acupuncture, deloading taping techniques, soft tissue massage and orthotics to offload the irritated nerve. One of the biggest factors in relieving pain may be changing or modifying your footwear. This may mean adding felt, foam or gel products to your shoe to help offload the area, or looking at avoiding tight fitting heels or shoes.
Surgery. This is the last and most permanent course of action. This surgery is used as a last resort as it often comes with a series of side affects including the risk of making the pain worse. This surgery can be performed by Orthopedic surgeons as well as Podiatric surgeons.
Ensuring that shoes are well fitted, low-heeled and with a wide toe area may help to prevent Morton's neuroma.