Point-Counterpoint: Is Conservative Care The Best Approach For Plantar Fibromatosis?
A Closer Look At The Efficacy Of Collagenase
On the treatment horizon is the possible intralesional injection of collagenase. The January 2011 issue of Harvard Men’s Health Watch presented an article entitled “Unfolding bent fingers: new handiwork for bacteria.”8 In 2010, the Food and Drug Administration (FDA) approved the use of collagenase Clostridium histolyticum to treat Dupuytren’s contracture of the hand. Currently, the medication does not have FDA approval for use in the treatment of plantar fibromatosis. One of the enzymes produced by Clostridium histolyticum is collagenase and collagenase destroys the collagen that makes up the fibrous material of the superficial (fascial) fibromatoses, including palmar and plantar fibromatoses.
In a large 2009 prospective, randomized, double-blind, placebo-controlled trial, Hurst and colleagues studied 308 patients with Dupuytren’s palmar fibromatosis.9 Each patient received three injections of 0.58 mg collagenase Clostridium histolyticum or placebo at 30-day intervals into their contracted fibrotic cord. The primary endpoint was a reduction in contracture to within five degrees of normal. Sixty-four percent of the collagenase injection group achieved this endpoint in comparison to 6.8 percent of the placebo group. The most commonly reported adverse events were localized swelling, pain, bruising, pruritus and transient regional lymph node enlargement and tenderness. The authors also reported three other more serious complications: two tendon ruptures and one case of complex regional pain syndrome (CRPS).
Several additional studies have supported these results and have confirmed that collagenase Clostridium histolyticum injections are well tolerated and effective for the management of Dupuytren’s contracture.10,11 Studies are currently underway to assess the value of collagenase in the management of plantar fibromatosis. Depending upon the results and safety profiles attained, the intralesional injection of collagenase may become the non-surgical treatment of choice in the near future.
A recent abstract at the 2012 American College of Foot and Ankle Surgeons’ Annual Conference in San Antonio, Texas highlighted the potentially positive benefit of collagenase for the conservative management of plantar fibromatosis.12
Other conservative modalities that may offer some hope for the management of the plantar fibroma include cryosurgery and radiofrequency ablation. There is very limited evidence supporting their efficacy at this time but the strong desire to avoid the potential adverse sequelae of more invasive surgical procedures makes these approaches desirable and worthy of further investigation.
When The Literature Reveals About Surgery And High Recurrence Rates
In my opinion, we relegate surgery to those patients who fail conservative treatment or have lesions that severely impair their immediate function. Historically, researchers advocated simple excision through a plantar medial incision.13,14
However, authors have reported limited local excision with very high rates of recurrence with the fibromatosis often worsening.15 Following simple excision, van der Veer and colleagues reported a 100 percent recurrence rate, Aviles and associates reported a 57 percent rate of recurrence, Allen and colleagues reported a 54 percent rate of recurrence, and Aluiso and co-workers reported a 40 percent recurrence rate.13,16-18
The consensus reason for the high rate of recurrence is incomplete excision.3,5,19-22 This most likely is explained by the lack of encapsulation of the lesion and the fact that it extends into what appears to be grossly normal surrounding plantar fascia that is in actuality histologically abnormal.3,5,23 Despite this growing body of evidence, many foot and ankle surgeons continue to employ limited local excision. Although some of these will be successful, the high recurrence rate makes a more invasive approach more palatable when patients require surgery.