A plantar fibroma is a knot in the arch of the foot. It can cause pain when repeated pressure is applied by walking barefoot or wearing tight shoes. While plantar fibromas can appear in anyone, men who are middle-aged or older are said to be more susceptible. The main symptom of a plantar fibroma is a firm lump on the arch of the foot. If there is pain, it can be intensified by putting pressure on the nodule. The lump can stay one size or grow larger. You may have one or more fibromas in the feet and there tends to be a high incidence of recurring plantar fibromas.  Generally, a plantar fibroma can be treated without surgery. Treatment might include steroid injections to help shrink the lump, orthotics to help redistribute weight away from the nodule, plantar fascia stretching, or physical therapy to help use anti-inflammatory medication on the lump. If a lump grows larger or more painful, a podiatrist can be consulted to confirm the diagnosis. The doctor will palpate the lump and this may cause pain that can be felt all the way to the toes. An X-ray, MRI, or biopsy might be done if further evaluation is necessary. A lump in the arch of the foot might be something other than a plantar fibroma, such as cysts, nerve or fatty tumors, swollen tendons, or an infection in the foot. It is important to see a podiatrist for proper diagnosis and treatment of plantar fibromas.