Medicine | Podiatry Help

Erythromelalgia is a distressing and difficult to manage condition that affects the hands and feet and is characterized by intermittent attacks with the triad of symptoms of redness, warmth and burning pain that can last from minutes to days. It needs to be differentiated from chilblains and burning feet syndrome. It has a significant impact on quality of life and the ability to carry out the activities of daily living.

Erythromelalgia is a rare and often debilitating vascular peripheral pain disorder characterized by episodes of redness, intense burning pain, warmth, and swelling, usually affecting the extremities—most commonly the feet and hands. The condition can be primary (idiopathic or genetic) or secondary to other diseases such as myeloproliferative disorders (like polycythemia vera), autoimmune diseases, or neuropathies. Symptoms are typically triggered or worsened by heat, exercise, stress, or wearing warm footwear, and are often relieved by cooling the affected areas. However, excessive cooling can lead to tissue damage, making symptom management a delicate balance.

The pathophysiology of erythromelalgia is not completely understood, but in primary forms, mutations in the SCN9A gene, which encodes the Nav1.7 sodium channel in sensory and sympathetic neurons, are known culprits. These mutations result in hyperexcitability of pain pathways, which likely explains the severe burning sensations patients report. In secondary erythromelalgia, the symptoms may result from increased blood flow due to microvascular dysfunction or from inflammatory processes. Diagnosis is clinical, supported by patient history, physical exam, and exclusion of mimicking conditions like cellulitis, Raynaud’s phenomenon, or peripheral neuropathy.

Management is challenging and varies greatly between individuals. Treatment typically focuses on symptom control and addressing underlying conditions if present. Common strategies include topical agents (lidocaine, capsaicin), oral medications (gabapentin, antidepressants, sodium channel blockers), and lifestyle modifications like avoiding heat exposure and elevating limbs. In severe refractory cases, more aggressive treatments like intravenous infusions, nerve blocks, or even sympathectomy may be considered. Because of the condition’s complexity and variability, a multidisciplinary approach—often involving neurologists, dermatologists, and pain specialists—is usually the most effective route for patient care.

Useful Resources:
https://podiatryarena.com/index.php?threads/erythromelalgia.110532/
https://podiapaedia.org/wiki/peripheral-vascular-disease/erythromelalgia/
https://themedicaldispatch.com/understanding-and-diagnosing-an-inherited-pain-syndrome/
https://articles.abilogic.com/539981/what-erythromelalgia.html
http://www.podiatryabc.com/e-is-for-erythromelalgia/
https://podiatryfaq.com/knowledge-base/what-is-erythromelalgia/
http://foot-health-forum.com/index.php?threads/erythromelalgia.125437/
https://footproblemsandthekitchensink.com/erythromelalgia-affecting-the-foot-throw-the-kitchen-sink-at-erythromelalgia/

Cancer can affect the foot either via a primary tumor in a tissue in the foot or as a secondary tumor from a more proximal metastasis.

Cancer can affect the foot in several ways, both directly and indirectly. Primary cancers of the foot are rare, but tumors can develop in the bones, soft tissues, or skin of the area. For example, malignant melanoma may arise on the skin of the foot, often mistaken at first for something less serious like a mole or wart. Bone cancers such as osteosarcoma or chondrosarcoma can also appear in the small bones of the foot, causing localized pain, swelling, and deformity. Because of the limited soft tissue around the bones in the foot, even small tumors may cause significant symptoms.

The impact of cancer on the foot can also come from metastasis. Cancers originating in other parts of the body, such as the lungs or breast, can spread to the bones of the foot, though this is uncommon. When it does occur, patients may experience persistent, unexplained pain that worsens at night or with weight-bearing activities. Metastatic lesions often weaken the bone structure, increasing the risk of pathological fractures in the foot, which can severely limit mobility and quality of life.

Treatment for foot cancers often involves a combination of surgery, radiation, and chemotherapy, depending on the type and stage of the tumor. Surgery might range from excision of small lesions to partial or full amputation of the affected area if the cancer is extensive. This can have profound consequences for walking, balance, and daily activities. Even when surgery is successful, rehabilitation and custom orthotic support are often necessary to restore function and reduce discomfort.

Beyond the direct effects of cancer, treatments themselves can also impact foot health. Chemotherapy and radiation may cause peripheral neuropathy, leading to numbness, tingling, or burning pain in the feet. These nerve changes can make walking difficult and increase the risk of injuries or ulcers, especially in patients with other conditions like diabetes. Additionally, reduced blood supply from radiation damage or surgical interventions can impair healing in the foot, making it especially vulnerable to infection and long-term complications.

Most Useful Resources:
Cancer (Foot Health Forum)
Cancer threads (Podiatry Arena)
Cancer metastasis in the foot (Podiatry Arena)
Cancer and the Foot (PodiaPaedia)
The Oncologist (Podiatry Apps)