26 Mar Plantar Fibroma & Fibromatosis
A plantar fibroma is a nodule that grows on the bottom of the foot. It is a benign condition that typically occurs in the 20s through 60s. It is usually slow growing and measures less than 1 cm. When there are numerous, invasive, rapid-growing and multi-planar fibromas, the condition is called plantar fibromatosis, which is also a benign condition. The exact cause of a plantar fibroma is not known. It is thought that trauma and phenytoin usage are potential causes. People with diabetes mellitus, hypothyroidism, epilepsy, and cirrhosis of the liver are also believed to have higher rates of plantar fibromas as well. Plantar fibromatosis is usually bilateral. Superficial plantar fibromatosis may grow gradually and recur when excised. Plantar fibromatosis is more common in the middle-aged to the elderly population. Juvenile aponeurotic fibroma is more prominent in younger males. Aggressive infantile fibromatosis and cerebriform mesodermic hamartomas typically occur within the first year of life.
Plantar fibromas may occur as either a single mass or in a cluster. They often occur within a ligament in the arch of the foot. As the mass grows, it causes symptoms of discomfort and pain for the person during walking. The diagnosis of a plantar fibroma is clinical, based on a focused clinical exam. A biopsy is not recommended because it can potentially enlarge the fibroma. Diagnostic imaging such as a plain film radiograph is needed to evaluate bony structures. Ultrasound can be performed and shows the local lesion as a hypoechoic mass but fails to show the true extent of the lesion. Magnetic resonance imaging (MRI) is useful for detecting plantar fibromatosis.
No treatment may be needed if the condition is painless. Otherwise, treatment of a plantar fibroma commonly involves padding in order to reduce the pain and pressure in the area. Foot orthotics, splints or night braces can be useful for this purpose. They can help stretch the plantar fascia ligament and reduce the size of the mass. Cortisone injections are not recommended in this condition and can be extremely painful. If these measures fail and the pain is persistent, surgical intervention to remove the plantar fibroma may be considered as a last resort. Surgical removal of the plantar fibroma also entails removal of most of the healthy plantar fascia ligament. This is because leaving the plantar fascia can lead to regrowth of the fibroma on it.
Once the surgery has been performed and the plantar fascia ligament removed, no weight bearing is allowed on the affected foot for a period of at least four weeks. Only when the foot has completely healed, gentle calf muscle strengthening exercises and gentle weight-bearing exercises are recommended. The patient will likely have to use crutches during that period until they can fully walk again.
Some possible complications of the surgery include infection, swelling, and numbness on the bottom of the foot. One common issue with this surgery scarring at the bottom of the foot that can be painful once it has healed. Recurrence of the plantar fibroma unless the entire plantar fascia is removed.