There has been a sore, aching spot on the bottom of your foot for the past month. With every stride you feel as if you are stepping on a pebble, and your toes tingle. You may have an enlarged, thickened nerve commonly referred to as a neuroma. A neuroma may develop in many areas of the body, but it is more common in the intermetatarsal space between two of the long metatarsal bones of the foot. The frequent location is between the third and fourth metatarsals, known as a Morton’s neuroma. The compression on the nerve at this anatomic location may lead to swelling and permanent nerve damage if left untreated.
The classic symptom of a neuroma is localized pain between the toes, and the feeling that there is a stone or that the sock is bunch up in the shoe. Tingling, burning, and numbing sensations may be present to the affected toes, especially when wearing shoes. The symptoms may last for several days or weeks, but massaging the area of pain may provide temporary pain relief. A neuroma is often caused by continuous irritation to the nerve from wearing tight shoes, running or playing racket sports, a previous injury or trauma to the area, and certain foot deformities such as flatfeet or hammertoes. Diagnosis of a neuroma can be made mostly by clinical evaluation. The standard clinical diagnosis of neuroma is made by palpating the symptomatic interspace with one hand, and compressing the outer sides of the entire foot with the opposite hand to feel for a palpable click, Mulder’s sign. No every patient with a neuroma will produce a palpable click, however, pain radiating in the digits will also be produced with this particular maneuver. Radiographs will be taken to ensure there is no fracture. An ultrasound or MRI may also be performed to rule out other pathologies, or if surgery will be required.
There are many options for conservative treatment of a neuroma. Wearing proper shoe gear, with a wider toe box along with metatarsal padding or orthotics may relieve the compression on the metatarsals and the associated pain. Medications such as nonsteroidal anti-inflammatory drugs (NSAIDS) will help reduce the inflammation and pain. If these initial therapies fail a corticosteroid injection may be done. The corticosteroid is mixed with a local anesthetic to relieve pain and reduce inflammation. A newer therapy for neuroma treatment is an alcohol sclerosing injection. It may take 4-7 injections for maximum relief to be obtained.
When these methods of conservative treatment fail there are two surgical approaches: a dorsal or plantar incision. The dorsal incision requires cutting the deep transverse metatarsal ligament as well as maneuvering around other delicate structures in the foot, before finally cutting out the pathologic area of the nerve. The patient will be able to put weight on the foot relatively soon after surgery. The downfall of this procedure is that the neuroma may grow back or a stump neuroma may form, bringing back the original painful symptoms. The dorsal incision approach may also lead to instability in the foot, which may also have to be corrected in the future. The second approach involves a plantar incision. The plantar incision involves cutting less tissue, and better visualization of the neuroma allowing for adequate resection of the nerve. There is less of a chance of the neuroma coming back, on the other hand sutures placed on the bottom of the foot means a longer recovery time. The patient may have to be non-weight bearing for up to 3 weeks.
A neuroma is an easily treated condition of the foot. See your local podiatrist to find out how your symptoms may be relieved.