summary Plantar Fibromatosis, also known as Ledderhose disease, is a benign tumor of the foot plantar fascia that is characterized by myofibroblast and collagen proliferation. The condition usually presents in elderly patients with subcutaneous thickening or nodules in the foot. Diagnosis is made with a combination of physical examination and MRI studies. Treatment is observation for minimally symptomatic lesions. Surgical excision is recommended for lesions that are large, painful, or activity-limiting. Epidemiology Incidence most common soft tissue neoplasm in the foot Demographics more common in males usually seen in middle-aged or elderly individuals can affect individuals of all ages Anatomic location bilateral in 25-50% Risk factors male gender Caucasian epilepsy repeated trauma diabetes long-term alcohol use chronic liver disease other fibrosing conditions (see below) Etiology Pathophysiology occurs in 3 phases proliferative phase characterized by increased fibroblast activity and cell proliferation involutional/active phase characterized by nodule formation residual/resting phase characterized by decreased fibroblast activity, collagen maturation, and scar/contracture formation Genetics unlike Dupuytren's disease, the genetic basis of plantar fibromatosis is unclear Associated conditions Dupuytren's disease occurs in 25% with Dupuytren's Peyronie's disease Anatomy Plantar fascia comprised of 3 bands: central, medial, lateral medial band most commonly affected originates from the medial and anterior aspects of the calcaneus divides into 5 digital slips at the MTP joints inserts on the base of the proximal phalanges Presentation Symptoms usually asymptomatic may become painful Physical exam inspection subcutaneous thickening or nodules usually on medial aspect of plantar foot digital contractures rare evaluate for the presence of other fibrosing conditions (Dupuytren's, Peyronie's) motion document ankle and hindfoot motion evaluate for the presense of Achilles tendon or gastrocnemius contractures Imaging Radiographs recommended views AP lateral findings usually normal MRI imaging study of choice findings nodular thickenings on the medial aspect of the plantar aponeurosis low signal intensity on T1-weighted images due to the relative acellularity and high collagen content of lesions low or medium signal intensity on T2-weighted images can have areas of high signal intensity if aggressive type Ultrasound findings multiple lesions embedded on the plantar fascia with sharp juxtaposition between the less reflective fibroma and the much brighter plantar fascia surrounding it comb sign alternating linear bands of hypoechogenicity and isoechogenicity relative to the plantar fascia represents the hyperechoic, fibrous regions of the fibroma on a background of hypoechogenic cellular matrix Studies Histology gross anatomy lobulated firm irregular mass histology dense fibrocellular tissue with mature collagen and fibrocytes in various stages of maturation no atypical features or abnormal mitotic activity Differential Post-traumatic neuroma Fibrosarcoma Clear cell sarcoma Treatment Nonoperative observation and supportive therapy indications first line of treatment lesions that are small or minimally painful modalities NSAIDs orthotics physical therapy corticosteroid injections Operative excision +/- radiation indications lesions that are large, painful, or activity-limiting Techniques Excision +/- Radiation technique total fasciectomy is preferred over local or wide excision due to risk of recurrence 57-100% recurrence with local excision 8-80% recurence with wide excision (2-3cm margins) 0-50% recurrence with total fasciectomy avoid incisions directly over nodules may lead to local recurrence due to intimate association of the nodule and skin if performing a partial fasciectomy, it is important to resect the nodule and the overlying skin may require skin grafting complications specific to this treatment skin necrosis nerve entrapment loss of arch height outcomes high rate of local recurrence with high-grade lesion consider postoperative radiation to minimize recurrence Complications Recurrence incidence occurs in 60% of excised lesions usually recurs as a more aggressive lesion risk factors bilateral disease multiple nodules family history of plantar fibromatosis prevention can perform adjuvant radiation Prognosis Malignant transformation is rare Recurrence is common after local excision usually recurs as a more aggressive lesion