Plantar fibroma - Foot and Ankle

Summary
Description

Plantar fibromatosis is a non-encapsulated thickening and proliferation of the central and medial bands of the plantar fascia.

People and Age
Patient's present in their second third and fourth decade.
Symptoms and Presentation
Most patients are asymptomatic, but some have activity related pain. One third to half of the patients have bilateral nodules.
Brief description of the xray
The lesion appears as a poorly defined area of thickening of the planter fascia with low signal intensity on both T1 and T2 weighted sequences.
Brief desc of tx
Initial management should consist of shoe modifications and pain medication.
Benign or Malignant
Body region
Most Common Bones
Complete Information on this Tumor
Introduction and Definition

Plantar fibromatosis (also known as Ledderhose's disease) is a non-encapsulated thickening and proliferation of the central and medial bands of the plantar fascia. This lesion is histologically similar to Dupuytren's contracture. Some patients have an inherited tendency to both palmar and plantar fibromas.

Incidence and Demographics
Patient's present in their second third and fourth decade, but these lesions may also occur in children, even babies. In 2 large series approximately 30 to 35% of these lesions occurred in patients under 30. Men are twice as commonly affected as women. Patients with palmar fibromas (Dupuytren's) are more likely to have plantar fibromas. Epilepsy, alcohol abuse, and diabetes may also be contributing factors. Trauma and occupational injury have been identified as possible causative factors, but the evidence to support these links is of poor quality. No particular occupational group has been identified, and the most common location of the lesion is in a portion of the plantar aponeurosis that is least likely to be injured.
Symptoms and Presentation

Most patients are asymptomatic, but some have activity related pain. One third to half of the patients have bilateral nodules. Pain occurs with weightbearing activities. When the lesions are large enough to press on the plantar nerves, there may be numbness or dysesthesia in the distal portions of the foot. In one pediatric patient, a large lesion caused contracture of the toe flexor tendons and loss toe extension in the lesser toes.

X-Ray Appearance and Advanced Imaging Findings
Plain radiographs do not define this lesion well, but two high quality, orthogonal radiographs are recommended, to rule out the presence of intralesional calcifications, which are a characteristic of synovial sarcoma but not of plantar fibroma.
MRI Findings
The MRI characteristics of the lesion are characteristic and allow this lesion to be differentiated from other more worrisome problems. Location is significant, and can be clearly defined by MRI. The lesion is typically centered within the medial band of the plantar aponeurosis, and the expansion of the fibers of the aponeurosis flowing into and around the lesion can usually be clearly seen. These lesions may appear as a poorly defined area of thickening of the planter fascia with characteristic low signal intensity on both T1 and T2 weighted sequences. The signal intensities may vary. Small lesions may be highly collagenized, with low signal intensity on both T1 and T2 images. However, in the author's experience, the larger lesions have less fibrous tissue, and less collagen and more cellularity, and as a result they have nonspecific high signal intensity on T2 weighted images.
CT Findings
Not typically useful.
Laboratory Findings
None recommended
Differential Diagnosis
synovial sarcoma
Preferred Biopsy Technique for this Tumor
Open
Treatment Options for this Tumor
Initial management should consist of shoe modifications and pain medication. Surgical removal is reserved for large lesions that are causing significant disability that have failed a well-documented course of non-operative care. Because recurrence is frequent following inadequate surgical removal, practitioners who are not prepared to undertake an aggressive and comprehensive resection of the lesion should not attempt to the procedure. Aggressive resection with a wide margin, as shown in the accompanying photos, is necessary to avoid recurrence, but may associated with significant complications. Although the procedure of choice has been given a term "radical fasciectomy", radical resection margins are not achieved. The actual margin achieved is typically a marginal to wide margin, where wide margins are achieved at the fascial boundaries of the lesion, but marginal margins are achieved on the skin surface of the lesion in order so that the skin may be closed without grafting, and marginal margins are achieved at the deep surface of the lesion in order to preserve the medial and lateral neurovascular bundles.
Preferred Margin for this Tumor
best available - see treatment discussion -
Outcomes of Treatment and Prognosis
In one series, the overall recurrence rate was 60%. The recurrence rate following "total plantar fasciectomy was 25%. "Local" or conservative resection was associated with a recurrence rate of 100%. (van der Veer et al, Plast Reconstr Surg. 2008 Aug;122(2):486-91.)