Morton’s disease (ICD code: G57.6), also known as Morton’s neuroma, refers to a disorder affecting the nerves on the sole of the foot. These nerves are part of the nervous system and form a delicate network with branches that supply the smaller toes.
This condition does not affect the motor functions of the toes, but rather their sensitivity. It is important that the toes can sense and respond to stimuli such as pressure or moisture.
In Morton’s disease, or Morton’s neuralgia, this sensory perception is impaired.
Morton’s disease is accompanied by severe nerve pain and other sensory abnormalities. After the pain syndrome was first noted by some surgeons as early as the 19th century, it was named after the physician T. G. Morton.
Interplay of Many Bones: Anatomy of the Feet © bilderzwerg / Fotolia
The condition results from compression or irritation of the nerves between the toes. The affected area is the metatarsophalangeal joints or the heads of the metatarsal bones.
Morton’s disease most commonly occurs between the third and fourth metatarsal bones (in the third interdigital space). Occasionally, it also occurs between the second and third interdigital spaces.
Multiple Morton’s neuromas on the same foot are also possible, though rare. Persistent compression of these foot nerves exerts pressure.
The resulting pain leads to chronic misalignment of the foot or poor posture. At the nerve branches, knot-like thickenings and tissue remodeling occur: the neuroma.
Thickened nerves in Morton’s disease © ellepigrafica / Fotolia
Morton’s disease is characterized by sensory disturbances in the forefoot or midfoot region.
What begins as a diffuse, uncomfortable sensation eventually develops into severe pain that radiates from the midfoot to the toes.
Since the sole of the foot is also affected by the pain in the forefoot nerves, Morton’s disease is also known as (Morton’s) metatarsalgia.
Patients with Morton’s neuroma complain of symptoms, particularly after prolonged walking and frequent “rolling of the foot.” This is often accompanied by numbness in the toes.
Both the pain and the numbness often occur in episodes. After an initial period without symptoms, pain suddenly shoots through the foot. The nerve pain can also occur spontaneously while sitting or lying down, even during sleep.
Morton’s neuroma often develops as a result of above-average stress on the forefoot. In particular, regularly wearing high-heeled shoes contributes to Morton’s disease.
Other contributing factors include:
- Hallux valgus (bunion)
- Foot deformities: flatfoot, splayfoot, pes cavus, and pes planus
- Foot injuries
- Foot surgeries
The constant nerve irritation caused by these conditions leads to nerve inflammation as well as scarring or thickening of the nerves, which further exacerbates the condition.
If your feet already have misalignments or you’re experiencing pain, it’s a good idea to consult an orthopedic surgeon.
Pain-free feet—not a given with Morton’s neuroma. © Valua Vitaly / Fotolia
The nature of the symptoms and the patient’s description usually point clearly to a Morton’s neuroma. The doctor examines the foot thoroughly. There are standard tests that provide information about the condition.
The typical tenderness over the metatarsal heads and pain when compressing the forefoot (Gaenslen maneuver) confirm Morton’s disease.
Further confirmation is provided by the Hohmann maneuver, which triggers pain when the metatarsal heads are shifted.
The doctor examines the painful foot using precise maneuvers. © JPC-PROD / Fotolia
Final confirmation is provided by injecting a local anesthetic into the affected space between the metatarsal bones.
X-rays remain unremarkable. Imaging techniques such as ultrasound or magnetic resonance imaging (MRI) do show tissue growths, but are not necessary for the diagnosis.
There are two treatment options for Morton’s disease:
- Conservative treatment
- Surgery
Conservative treatment
The first line of treatment is outpatient conservative therapy. In this approach, doctors treat the inflammation of the nerves in the foot. Injections of cortisone preparations have proven effective here.
Because the nerves in the foot are highly sensitive and painful, doctors must first dilute these preparations with a local anesthetic. One or two injections, spaced six weeks apart, are almost always sufficient. Afterward, the pain usually subsides.
Conservative therapy with cortisone injections can lead to post-injection bleeding or infections. Following infections, bruising occasionally occurs, which subsides after one to three days.
Thinning or discoloration of the skin is rare. Some patients may experience hypersensitivity or an allergic reaction to the cortisone or anesthetic.
Surgical Treatment
If the nerve tissue shows scarring or thickening, or if cortisone injections are ineffective, surgery is the next step in treatment.
This requires an inpatient hospital stay. The surgeon treats the nerve inflammation and thickening surgically with the goal of neurolysis (nerve removal) and decompression (pressure relief).
In this procedure, the surgeon removes the Morton’s neuroma. As a result, the majority of patients experience relief from their symptoms or a satisfactory improvement in their condition.
As with any other surgery, there may be side effects associated with Morton’s neuroma surgery.
The following complications are possible:
- Postoperative bleeding
- Wound healing disorders and
- Infections
Pain at the nerve stump or scar-related discomfort are other possible undesirable consequences of the surgery.
In addition, there are the usual surgical risks, such as embolisms, thromboses, or complications caused by pre-existing conditions.
Before the surgery, you will receive an informational brochure about the planned procedure. During the preoperative consultation with your doctor, you will also have the opportunity to ask any remaining questions.
In the first few days after surgery, the doctor will change the dressing daily. Later, you can do this yourself.
As the healing process progresses, a bandage or adhesive bandage will suffice. If the incision is made on the sole of the foot, you will be provided with a non-weight-bearing shoe or a bandaged shoe for approximately three weeks. Once the wound has healed, your doctor will remove the sutures.
Immediately after surgery, pain may recur (phantom pain) despite the removal of the painful nerve tissue. This pain almost always subsides after a few weeks, once the treated tissue has regenerated. The scar may also be painful at first. Overall, most treatments for Morton’s disease are successful.
To promote the fastest possible reduction of swelling and wound healing, you should minimize standing and walking. Elevate your foot while sitting. Elevating your foot protects it and helps prevent blood clots by improving blood circulation. Cold compresses help reduce swelling and relieve post-operative pain.
As a preventive measure, you should choose flat shoes instead of high heels. Soft insoles—or, if necessary, orthopedic, custom-fitted insoles—increase the forefoot’s ability to bear weight while standing and walking.
Special foot exercises that strengthen the arch and tone the feet are a good preventive measure, as long as you are pain-free. If you are already experiencing symptoms, you should first consult a doctor or physical therapist.
What are the typical symptoms of Morton’s neuroma?
The main symptom of Morton’s neuroma is sudden, shooting, stabbing, or burning pain in the forefoot, which often radiates into the toes. Those affected frequently report a sensation of a foreign object in their shoe, as if there were a crease in their sock. In addition, numbness or tingling may occur in the area of the third and fourth toes. The pain typically worsens when walking in tight shoes and subsides when you take off your shoes and massage your foot.
How is a Morton’s neuroma diagnosed?
A suspicion of a Morton’s neuroma often arises simply from the patient’s description of the symptoms. During a clinical examination, the doctor compresses the forefoot laterally, which can trigger a characteristic pain or a clicking sensation in cases of Morton’s neuroma. To rule out other causes and determine the exact location and size of the Morton’s neuroma, imaging studies using MRI (magnetic resonance imaging) or ultrasound are recommended. An MRI also helps distinguish the neuroma from other space-occupying lesions.
What factors contribute to the development of a Morton’s neuroma?
A Morton’s neuroma usually develops as a result of chronic mechanical irritation of the nerve. A major risk factor is wearing high-heeled or overly tight shoes that compress the metatarsal bones. Foot deformities such as splayfoot or hallux valgus can also contribute to the development of a Morton’s neuroma, as they lower the arch of the foot and increase pressure on the nerve between the metatarsal heads.
What does conservative treatment for a Morton’s neuroma involve?
In many cases, conservative treatment is sufficient at first. The most important component is adjusting footwear and using a special insole that cushions the forefoot and supports the transverse arch. Physical therapy can help strengthen the foot muscles. For acute pain relief, anti-inflammatory medications or an injection of cortisone and a local anesthetic can be administered directly to the nerve to reduce swelling.
When is surgery for a Morton’s neuroma necessary?
Surgical treatment of a Morton’s neuroma is recommended when all conservative measures have failed to bring about improvement over several months and the patient is experiencing significant distress. The goal of the surgery is to eliminate the constant pressure on the nerve. This is achieved either through decompression—that is, creating more space—or through the complete removal of the Morton’s neuroma, which, however, leads to permanent numbness between the toes.
What is the postoperative care like?
After surgical treatment of Morton’s neuroma, it is important to rest the foot so as not to compromise wound healing. Patients with Morton’s neuroma are usually prescribed a forefoot-relief shoe, which they must wear for about two to four weeks after surgery. Once the stitches are removed, patients can gradually transition back to normal, roomy footwear. It usually takes six to eight weeks for full weight-bearing capacity to be restored during sports activities following treatment for a Morton’s neuroma.
Can a Morton’s neuroma go away on its own?
A true Morton’s neuroma is a structural thickening of the nerve tissue (fibrosis) that usually does not resolve completely on its own. However, consistent conservative treatment that relieves pressure on the nerve can cause the swelling around the neuroma to subside and the symptoms to disappear. True regression of a Morton’s neuroma—in the sense of the nodule disappearing—is rare without surgical removal, however.
Are there specialists for Morton’s neuroma?
Yes, diagnosis and treatment should be handled by specialists in orthopedics and trauma surgery who specialize in foot surgery. The clinical picture is discussed extensively in the international medical literature, such as in the *Journal of Bone and Joint Surgery* or in the field of foot and ankle surgery. A doctor specializing in Morton’s neuroma is best suited to assess whether conservative treatment is sufficient or whether surgery is the best option.
