A Plantar Fibroma (pronounced plan-tar fy-broma) is a lump on the bottom of the foot. It is associated with a hereditary condition called Dupuytren’s Contracture (you’re on your own with the pronounciation of Dupuytren’s. After four years of medical school and two years of residency, I have yet to find two physicians who pronounce it the same way). This condition can affect the hands and the feet. A Plantar Fibroma can be seen in just one foot or both. The most common site is in the mid-arch area. It can vary in position from very proximally, just in front of the heel, to very distally, just behind the ball of the foot.
A Plantar Fibroma is usually painful, but in some instances it is not painful initially, just an annoyance. It is usually painful as it progresses. This is due to the fact that it is quite a firm mass that gradually increases in size over time.
Etiology (Cause) of Plantar Fibroma
Other than the fact that it is related to Dupuytren’s Contracture, a common affliction of the palms of the hands, there is not much known about the etiology of Plantar Fibroma. The most accepted causative factor is injury to the structure involved. The major structure involved is the Plantar Fascia (pronounced plan-tar fasha). If there is injury to the Plantar Fascia that causes even a small tear, patients with a tendency for fibroma formation will start to see a small lump form in the area of injury. As previously stated, the initial pain of the injury may be long gone when the Plantar Fibroma starts to form. A good example to equate to this is a person who forms a thickened, firm scar. You can have two patients with the exact same incision and six months later, the incision is invisible in one of those patients and it is a thickened, raised, firm almost angry red in the other. The second patient is referred to as a Keloid-former (you will find an entire section on this condition). They just tend to form more scar tissue.
In Plantar Fibroma, the scar tissue formation is occurring at the site of the Plantar Fascia tear. It continues until gradually over time, there is a firm mass over the entire site of injury in the Fascia. It then continues to grow. The position will vary depending on the exact site of the injury. The mass is somewhat self-limiting in size. The largest I have seen in 14 years of private practice is 5cm long by 3cm wide by 2cm deep (2 inches long by 1 ¼ inches wide by ¾ inch thick). When they reach this size, they start to cause pressure on all the soft tissue and bony structures around them.
Signs and Symptoms of Plantar Fibroma
The signs of Plantar Fibroma are simple. You see a lump on the bottom of the foot (in the arch) and it seems to be getting larger over time. As for symptoms, this is tougher for the patient to put their finger on, literally. Prior to the lump forming, there may be pain initially at the site of the lesion. The patient can press on the area and feel pain. There can sometimes be pain when walking or standing also. In patients who already have a tight Plantar Fascia or those suffering from Plantar Fasciitis, the Plantar Fibroma will progress more quickly. As the mass increases in size, it starts to put pressure on other soft tissue structures in the area. It can press on tendons, ligaments, muscles, blood vessels or nerves. It is usually the pressure on the nerves that causes the pain. When the nerve pressure continues for some time, inflammation of the nerve becomes more chronic. Prior to the inflammation of the nerves, the lesion is only painful on weightbearing (standing and walking). When the chronic inflammation of the nerves arises, the pain becomes evident even when the patient is sitting. The nerve will hurt on initial standing in the morning and walking early in the day. As the day progresses, the nerve will become less painful as it essentially shuts itself down. When the patient sits later in the day, the nerve “comes back to life.” There can be tingling, burning, sharp, shooting, stabbing, electric sensations localized to the area or radiating up into the toes or back into the heel and ankle.
Conservative treatment options for Planta Fibroma
- Changes in shoes to include more supportive sport/walking shoes that have a softer footbed.
- Oral anti-inflammatories including over-the-counter medications such as Advil, Motrin and Aleve may help acute flare-ups.
- Prescription-strength anti-inflammatories prescribed by a Physician.
- Anti-inflammatory injections (cortisone-type medications) into the mass and the surrounding areas to decrease the inflammation.
- Stretching exercises-this may worsen the problem as it stretches the area of tear.
- Massage including tennis ball or frozen water bottle massage of the arch-as with stretching, this may worsen the problem.
- Taping or strapping of the foot/arch/ankle to take the pull off the Plantar Fascia is a very good diagnostic tool.
- Longterm conservative treatment should include custom molded functional orthotics. When this device has an accommodation for the mass, this is the best conservative treatment for Plantar Fibroma.
Further treatment after the above conservative options have failed
Surgical intervention may become necessary when all conservative options have failed to bring adequate relief of symptoms. The most commonly accepted treatment is excision of the mass from the Plantar Fascia or Plantar Fasciectomy. The conventional incisional approach is a 1 ½- to 3-inch curved incision on the bottom of the arch just to the side of the mass. The entire mass is removed by cutting the ligament in front of and behind the mass. The procedure is performed in an outpatient surgical facility and usually requires several weeks of using crutches and not putting any weight at all on the foot. Typically, someone who stands and walks quite a bit at work will require at least 8 weeks off work. Someone who sits at work may return as early as a week after surgery, but still on crutches and not putting any weight on the foot.
The newest treatment for Plantar Fibroma is Cryoanalgesia(Cryosurgery or cryo). This is performed through a small 3mm incision just to the side of the mass. The cryoprobe is directed using a Digital Diagnostic Ultrasound to several sites within the lesion and the procedure is performed like a typical cryo procedure. There is no cutting of the ligament as in the Conventional Plantar Fasciectomy, which can usually lead to functional instability of the entire foot. This procedure is performed in the office under local anesthesia. It typically takes 20-30 minutes. The pain from the lesion is typically decreased dramatically within 2-3 days and the lump is visibly decreased in size within a few days to weeks. It gradually continues to decrease in size over the next few months as the pain stays gone for 3 months or more. By that time, the mass is essentially gone and so is the pain. Larger masses will tend to take longer to completely resolve. Sometimes, these larger masses do not completely resolve and the procedure must be repeated. To date, most patients who have had this procedure and not seen complete resolution of the lesion have related significant relief of the pain associated with the lesion, so overall they were happy with the post-operative results.
The most important note is that with Conventional Plantar Fasciectomy there is a very high recurrence rate. The mass can come back within several years, sometimes within 6 months. It then requires re-excision. Because of the fact that these patients are inherent scar-tissue formers, there will be significant scar tissue in the area afterwards. This can lead to scar tissue entrapment of the very nerve structures that were causing pain to begin with. The more times the mass is excised, the more scar tissue present. With the damage to the skin and soft tissues after multiple surgical excisions, poor healing can be seen as a likely outcome. In some cases, a non-healing wound may develop and require skin grafts or other plastic repair of the skin and underlying soft tissues.
When we use Cryoanalgesia (cryo) for the treatment of Plantar Fibroma, there is also a chance of recurrence. Of all the conditions treated with UltraCryo, this has been one of the biggest surprises. When we initially started doing this procedure, we were wary that the lesions may return as soon as a year or less after treatment since this was the case when conventional excision was performed. We have now performed in excess of 225 procedures with very minimal recurrence in the 7 years we have been performing the procedure on fibromas. Otherwise, it should be further noted that there is minimal scar tissue formation with cryo of the lesion. In addition, this procedure is repeatable as many times as we need to perform it without any discernible increase in scar tissue.
Inherent in the Cryosurgical approach to treatment of Plantar Fibroma is the softening of the lesion during the freezing process. The established strong collagen cross bonds of the mass are broken during the freeze-thaw process. Because of this process, the softer, more pliable lesion is seen immediately after the procedure. In addition, the inflamed nerves underlying the mass are treated simultaneously as we perform the procedure, so the pain is decreased almost immediately.
Post-operatively, patients relate similar results as with patients who have the Cryo procedure for Plantar Fasciitis. 80% of those patients related an 80% decrease in the original pain/discomfort level within days of the procedure. In those patients that had the problem in the other foot treated with Conventional Plantar Fasciectomy and were treated with Cryo in the second foot, they related a much faster healing course and much less lost time from work. They responded favorably to Cryo and would have the procedure done again if necessary.