Piezogenic Pedal Papules
Updated: Jun 15, 2022
Author: Christopher R Gorman, MD; Chief Editor: William D James, MD
Overview
Practice Essentials
Piezogenic papules are painful or asymptomatic papules of the feet and wrists that result from herniation of fat through the dermis. They are common, nonhereditary, and usually are not the result of an inherent connective tissue defect. Piezogenic papules of the wrist were reported in 1991.[1] They are found in a large number of asymptomatic people. See the image below.
Piezogenic pedal papules. Courtesy of DermNet New Zealand (https://www.dermnetnz.org/assets/Uploads/dermal-infiltrative/piezogenic-papules5.jpg).
Prognosis
In most patients, the condition is of cosmetic concern only. Painful papules are less common and may correlate with Ehlers-Danlos syndrome (EDS), Prader-Willi syndrome,[2] obesity, and occupational or sporting exposure. Painful papules can limit participation in sports and may affect occupational activity.[3, 4]
Diagnostics
Piezogenic papules are diagnosed clinically. No laboratory evaluation is required.
No imaging studies are required. Ultrasound and high-frequency ultrasound have been described in the evaluation of this condition.[5, 6]
The histologic finding, which is identical in wrist and foot papules, is herniation of fat through the dermis. This is believed to result from poor compartmentalization of fat because of thinner-than-normal fibrous trabeculae in subcutaneous tissue. The process is not inflammatory.
Treatment
The literature does not suggest any effective surgical therapy.
No effective oral or topical medical therapy is available for this condition. Because the problem is strictly cosmetic for most individuals, therapy is rarely needed. Orthotics may be of benefit to symptomatic individuals, and rest and elevation help with symptoms.
Patients with Ehlers-Danlos syndrome (EDS) may be at risk for healing complications following surgical intervention. However, in 2004, Doukas et al[7] reported a nonsurgical approach for piezogenic papules. They injected betamethasone and bupivacaine in equal parts (1-2 mL/injection) into an EDS patient and reported 50% relief of pain with one injection. Three months later, a second injection yielded a further 20% reduction in pain. After 5 more months, a third injection yielded total relief of pain. At 5-year follow-up, the patient remained asymptomatic.
Turkmani reports the successful treatment of a single case of piezogenic pedal papules using lipolysis with injection of deoxycholic acid (DCA).[8]
Consultations
Consultation with an orthopedic specialist or podiatrist may be indicated if the diagnosis is uncertain, if patients are symptomatic, or if a second opinion is desired in patients with disability. Consultation with a cardiologist may be indicated if evidence of mitral valve prolapse is found on examination.[9]
Activity
Restriction of standing, walking, and running may be helpful for the unusual patient with painful papules. Elevation of the feet temporarily relieves the herniation.
Prevention
Weight loss and avoidance of prolonged standing may be helpful for symptomatic patients if, according to the history, these factors are contributing to the symptoms.
Pathophysiology
Herniation of fat into the dermis causes the papular appearance. The papules become apparent when an individual stands with full weight on the heels, and they resolve when the weight is removed. The papules, which usually occur bilaterally, may be present on the medial, posterior, and lateral aspects of the heels. Similar papules arise on the volar wrists when pressure is applied.
The histology is similar in both wrist and heel papules, revealing fragmentation of dermal elastic tissue and herniation of subcutaneous fat into the dermis.
Usually, no hereditary diseases or syndromes are associated with the papules, although they have been reported in some patients with Ehlers-Danlos syndrome (EDS).[10, 11] Piezogenic pedal papules have also been noted to occur in the presence of GATA2 deficiency.[12]
Etiology
No specific causes are attributed to the herniation. The condition has occurred within families,[13] but most cases are believed to be sporadic. Piezogenic papules may be more common in people who are overweight, as well as in individuals with orthopedic problems including flat feet. However, they also can occur in newborns with no clear predisposition. Piezogenic papules may occur more commonly in persons with collagen disorders such as Ehlers-Danlos syndrome (EDS).[10, 11]
Epidemiology
Frequency
United States
In the United States, 76% of a studied population has been found to have pedal papules; 86% have wrist papules. These occur in all age groups. Most patients are asymptomatic, although the papules can be painful. Painful papules were found in approximately one third of 29 patients with Ehlers-Danlos syndrome (EDS).
International
Piezogenic papules occur worldwide. Both American and European studies report an incidence of approximately 10-20% in the populations studied. In a report from India in 1995, 100 people were examined for piezogenic papules. Of these individuals, 80 had pedal papules, 86 had wrist papules, and 74 had both pedal and wrist papules.[14]
Race-, sex-, and age-related information
No evidence exists of racial or hereditary predisposition, except in piezogenic papules that arise in association with EDS.
Painful piezogenic papules are reported more frequently in women than in men.
Painful papules occur in persons of any age, even children. Infantile pedal papules are seen in 6% of newborns and 40% of infants. Infantile pedal papules differ from adult piezogenic papules. Infantile pedal papules are nodules, occur in the medial plantar aspect of the foot, and lack a piezogenic factor.[15, 16]
Presentation
History
In most cases, lesions are asymptomatic and are noticed incidentally by affected individuals. Lesions persist and no treatment is required; however, painful papules may be noticed because of associated symptoms.
If the condition is painful, patients may report limitation of occupational or sporting activities.
Piezogenic papules may be more common in people who are overweight, people with flat feet, and people who spend significant time on their feet.
Adult piezogenic pedal papules are more common in women than in men.
Piezogenic pedal papules were seen in 34% of a series of patients with Ehlers-Danlos syndrome (EDS), probably resulting from the underlying connective tissue defect.
Physical Examination
The signs of the condition include herniated papules of fat, usually compressible, mostly in the lateral heels. Examine patients standing with their full weight on the heels. Papules may be present on the medial, posterior, and lateral aspects of the heels. They usually occur bilaterally. The papules are typically 2 mm in diameter.
Papules resolve when the weight is removed. Similar papules may arise on the volar wrists when pressure is applied.
DDx
Diagnostic Considerations
Infantile pedal papules are fairly common, nontender, congenital nodules located on the medial plantar aspects of the foot. This condition has been described as precalcaneal congenital fibrolipomatosis hamartomas, bilateral congenital adipose plantar nodules, benign anteromedial plantar nodules of childhood, congenital piezogeniclike pedal papules, bilateral congenital fatty heel pads, and pedal papules of the newborn. They are most common at age 1 year and typically disappear between ages 2 and 3 years. Infantile pedal papules do not accentuate upon standing. The etiology is unknown.
Autosomal dominant precalcaneal congenital fibrolipomatous hamartoma is rare.[17, 18] Lesions were flesh colored and in the midline of each heel (plantar). They are symmetric and bilateral. These persisted up to puberty and beyond (age 20 y) in one case. Histologically, they are mature adipose tissue. No other associated malformations were reported.
Acrokeratoelastoidosis of the foot may be mistaken for piezogenic pedal papules.[19]
Differential Diagnoses
Medication
Medication Summary
The goals of pharmacotherapy are to reduce morbidity and to prevent complications.
Corticosteroids
Class Summary
Glucocorticoids have profound and varied metabolic effects. In addition, these drugs modify the body's immune response to diverse stimuli.
Betamethasone, systemic (Soluspan, Celestone)
Betamethasone decreases inflammation by suppressing the migration of polymorphonuclear leukocytes and reversing increased capillary permeability.
Local anesthetics
Class Summary
Local anesthetics are used to relieve pain
Bupivacaine (Sensorcaine, Marcaine)
Bupivacaine may reduce pain by slowing nerve impulse propagation and reducing action potential, which, in turn, prevents initiation and conduction of nerve impulses