Neuromas

Anatomy

Peripheral nerves are soft tissue structures that carry signals between the brain and spinal column to the rest of the body. Peripheral nerves carry signals to the foot and ankle and control functions including sweating, ability to sense pain, and muscle movement. Nerves travel from the spine and down the legs and terminate in the feet.

Condition

Neuroma is a term used to describe a thickening of nerve tissue. Neuromas can develop in any part of the body including the foot. The most common location for a neuroma in the foot is the distal 3rd intermetatarsal space. This is known as a Morton’s neuroma and it causes pain in the 3rd intermetatarsal space and to the 3rd and 4th toes. Neuromas result from compression or irritation of the nerve. Intermetatarsal neuromas result as the nerve is compressed between the metatarsal heads and the intermetatarsal ligament.

Symptoms

1. Pain at the location of the neuroma
2. Burning, tingling, or numbness that typically radiates to the involved toes
3. Having the sensation that something is in the bottom of the foot or something is bunched up in the sock
4. Thickening of the tissue or a clicking sensation when the tissue is palpated
5. Symptoms are typically worse with shoes as there is compression of the metatarsal bones therefore aggravating the neuroma

Diagnosis

Diagnosis is made by a comprehensive foot and ankle exam by Dr. Stewart. Ultrasound, MRI, and electromyogram (EMG) and nerve conduction studies are sometimes utilized when making the diagnosis.

Common causes

1. Poor fitting shoe gear, especially high-heels or shoes with a tapered toe box as they contribute to compression
2. Flatfoot deformity
3. Structural deformities or tendon and muscle imbalance
4. Overuse, which means there is too much physical activity. This commonly occurs in runners and/or walkers and in such sports as soccer, lacrosse, basketball, tennis, and football
5. Flexible feet
6. Obesity

Treatment

Conservative care is the 1st line of treatment when treating a neuroma. Dr. Stewart will exhaust all surgical treatment prior to recommending surgical intervention.

Conservative treatment for neuromas includes:

1. Steroid injections
2. Ice and elevation
3. Custom foot orthotics with off-loading pads
4. Nerve ablation procedures
5. Weight loss
6. Medications including anti-inflammatory medications (NSAIDs), Tylenol, oral steroids, and in some cases narcotic pain medication
7. Avoidance of flip-flops, flats, and barefoot walking
8. Modification of physical activity including avoidance of walking, jogging, running, and the elliptical for exercise. Recommended exercises include circuit training, swimming, and bicycling
9. Supportive shoe gear including a motion control running shoe such as Brooks, Asics, New Balance, or Saucony. Keen and Merrell style shoes are also recommended
10. Modification of physical activity to lower impact activities

In certain circumstances, conservative treatment is insufficient to treat a neuroma and surgical intervention is required. With surgery, the neuroma is excised. This results in permanent numbness along the distribution of the excised nerve. Surgery is generally successful, yet patients need to be aware that nerves can be very difficult to treat and there is always the possibility of developing what is known as a stump neuroma. A stump neuroma is a neuroma that forms at the level the nerve was transected and excised. Treatment of a stump neuroma is similar to treatment of the original neuroma.