Long COVID and Your Feet: What's Really Happening Below the Ankle.

By WeTreatFeet Podiatry | The Podiatry Voice

The Pandemic Didn't End for Your Feet

Most people think of Long COVID as shortness of breath, brain fog, or crushing fatigue. And while those symptoms get most of the headlines, there is a growing body of evidence that the lower extremities are taking a serious hit too. At WeTreatFeet Podiatry, we have been watching this pattern unfold in our exam rooms since 2020, and what we are seeing lines up directly with what researchers are now documenting in the literature.

If your feet have been burning, aching, swelling, or simply not feeling right since you had COVID-19 — and nobody has been able to give you a satisfying answer, keep reading. This is written for you.

How Many People Are Actually Affected?

The numbers are staggering and, depending on which study you reference, they may be significantly higher than what federal health agencies have reported.

A 2024 national survey estimated that approximately 17.8 million U.S. adults. Roughly 6.9% of all American adults — had experienced Long COVID at some point. More recently, a 2026 study out of Mass General Brigham that analyzed nearly 458,000 patients across four U.S. regions found a prevalence of approximately 16%, which, when extrapolated to the full U.S. population, would represent an estimated 54 million Americans who developed Long COVID.

At least 10% of people infected with SARS-CoV-2 develop persistent symptoms lasting months to years. The WHO defines Long COVID as symptoms that persist beyond three months after infection without another explanation. That is tens of millions of people walking around with a condition that remains poorly understood and undertreated, especially from a podiatric standpoint.

What the Science Says About Why Feet Are Affected

Understanding Long COVID foot symptoms requires understanding what the virus, and specifically its spike protein, does to the body at a cellular level. There are several distinct mechanisms at work here, and they overlap in ways that explain why foot pain after COVID can be so varied, so stubborn, and so hard to treat with conventional approaches.

The Spike Protein Problem

The SARS-CoV-2 spike protein is not just a structural feature of the virus. It is biologically active, and it does not necessarily leave when the acute infection resolves.

Research published in 2023 in Clinical Infectious Diseases found that circulating spike protein was detectable in a subset of Long COVID patients months after their initial infection, suggesting the presence of an active viral reservoir, most likely in the gut, that continues releasing antigen into the bloodstream. A 2021 study confirmed the presence of amyloid fibrin microclots resistant to normal fibrinolysis (the body's natural clot-dissolving process) in the plasma of Long COVID patients, and these microclots have been directly linked to impaired microcirculation.

More recently, German researchers at Helmholtz Munich and Ludwig-Maximilians-Universität published findings in Cell Host & Microbe showing that spike protein can persist in the skull's bone marrow and meninges for up to four years after infection, potentially driving chronic neuroinflammation. Meanwhile, a 2025 study confirmed that viral spike transcript and protein persist in the gut tissue of Long COVID patients, where it is associated with active immune dysregulation and a dysfunctional pro-inflammatory transcriptional profile.

In 2023, serum analysis demonstrated that both natural infection-derived spike protein and vaccine-derived spike protein may persist in long-COVID patients well beyond what early studies predicted. For individuals with viral persistence, more than 50% had a greater likelihood of developing Long COVID symptoms.

A key point here: the half-life of spike protein under normal circumstances is relatively short. When researchers find it circulating in blood months or years later, the most credible interpretation is that there is ongoing production from a persistent viral reservoir somewhere in the body not simply that the original protein lingered.

The Microclot and Vascular Connection

The spike protein binds to ACE2 receptors, which are abundantly expressed on endothelial cells (the cells that line every blood vessel in the body), including the smallest capillaries in the feet. When these receptors are disrupted, the result is endothelial dysfunction: the vessel walls become inflamed, lose their ability to regulate blood flow properly, and the stage is set for abnormal clotting

These fibrinoid microclots are structurally different from normal clots. These are amyloid-like in nature, meaning they resist the body's standard enzymatic dissolution processes. When microclots accumulate in the microcapillaries of the feet, oxygen and nutrient delivery to foot tissues becomes compromised. This is not a trivial finding. The feet are the furthest point from the heart, dependent on healthy microvascular flow, and disproportionately vulnerable to any systemic circulatory disruption

Research published in Frontiers in Cardiovascular Medicine confirmed persistent microclots in Long COVID plasma and their role in a thromboinflammatory cycle that can affect multiple organ systems. Additional vascular research confirmed that angiotensin-converting enzyme 2 (ACE2) downregulation leads to a cascade of cardiovascular complications directly linked to Long COVID persistence.

The Nerve Damage Problem: Small Fiber Neuropathy

Perhaps the most clinically significant finding for podiatrists is the relationship between Long COVID and small fiber neuropathy (SFN).

A 2025 analysis of 977 Long COVID patients at the University of Texas at Austin found that 55% reported neuropathic symptoms. Of those who underwent skin punch biopsy, 56.5% had confirmed small fiber neuropathy, with damage to both epidermal and autonomic nerve fibers. Critically, small fiber neuropathy in Long COVID patients was not fully explained by conventional risk factors like diabetes, vitamin deficiency, or alcohol use, suggesting a distinct, COVID-specific mechanism.

That mechanism appears to be autoimmune in nature. The same study found that approximately one in four Long COVID neuropathy patients had elevated anti-ganglioside antibodies (AGAs)(which are the same class of autoantibodies associated with Guillain-Barré Syndrome) compared to none of the controls. These antibodies remained persistently elevated up to 1.5 years post-infection, which may directly explain why neuropathic symptoms in the feet do not simply resolve over time.

Yale Medicine has documented that this small fiber neuropathy in Long COVID frequently manifests as burning pain in the feet, tingling, and numbness, beginning distally and spreading proximally. This represents a classic length-dependent pattern.

A 2024 systematic review further confirmed increasing associations between Long COVID and small fiber neuropathy, with peripheral nerve involvement encompassing small fiber, large fiber, plexopathy, and autonomic fiber damage.

Musculoskeletal Consequences

A 2025 meta-analysis of 64 studies found that muscle pain affected 28% of Long COVID patients, with joint pain affecting nearly 15%. These numbers held even at the 12-month mark post-infection, indicating that musculoskeletal symptoms are not simply a short-term post-viral phenomenon.

A 2025 observational longitudinal study published in Scientific Reports documented persistent neuromuscular disorders in Long COVID patients, specifically involving changes in the architecture of the tibialis anterior and gastrocnemius lateralis muscles, two muscles directly responsible for foot and ankle mechanics. When these muscles are structurally compromised, the downstream effects on gait, plantar pressure distribution, and tendon loading are significant.

The Specific Foot Conditions We Are Seeing

Based on both the clinical literature and patterns we have observed at WeTreatFeet Podiatry, Long COVID is driving or exacerbating several distinct foot conditions:

Burning Feet and Peripheral Neuropathy

The most common Long COVID-related foot complaint. Burning, stinging, or electric-shock sensations (especially at night) that are disproportionate to any identifiable structural cause. This is the clinical signature of small fiber neuropathy. It frequently begins in the soles of the feet and can progress up the legs.

Post-COVID Plantar Fasciitis

There has been a notable increase in chronic, treatment-resistant plantar fasciitis cases presenting post-pandemic. These patients are atypical, even often healthy, fit individuals without the traditional risk factors. They might have developed heel pain during or shortly after COVID quarantine, and who do not respond to the standard conservative treatment algorithms. The working theory involves a combination of deconditioning, musculoskeletal atrophy from inactivity, and possibly direct COVID-related tissue inflammation

COVID Toes (Pernio-Like Lesions)

Known clinically as pernio or chilblains, COVID toes present as painful, red or purple discoloration on the toes. this was initially associated with acute COVID-19 but documented as a persistent finding in some Long COVID patients. The histopathology shows evidence of vascular inflammation consistent with the endothelial dysfunction described above.

Achilles Tendinopathy and Peritendinous Swelling

Post-viral inflammation and vascular compromise can affect tendon health. Musculoskeletal sequelae of PASC include tendon-related symptoms that often present without obvious mechanical cause

Foot and Ankle Swelling (Edema)

Vascular and lymphatic disruption associated with Long COVID can drive dependent edema in the lower extremities. This is especially relevant in patients with autonomic dysfunction (dysautonomia), where impaired vascular tone leads to blood pooling

Dysautonomia-Related Foot Symptoms

A subset of Long COVID patients develop POTS (Postural Orthostatic Tachycardia Syndrome) or other forms of dysautonomia. The feet, and particularly the circulation and sweating function, are directly impacted. Patients may notice color changes, temperature asymmetry, or excessive/reduced sweating in the feet

The Science Behind Treatment: What We Know So Far

There is no single, FDA-approved protocol for Long COVID. What exists is an evolving body of evidence pointing toward several promising approaches, particularly for the vascular and neuropathic components that affect the feet most directly.

Anti-Inflammatory and Fibrinolytic Support

Given the microclot and thromboinflammatory mechanism, researchers and clinicians have explored natural fibrinolytic agents:

• Nattokinase (2000 FU / 100 mg twice daily) has demonstrated in vitro fibrinolytic properties and in silico evidence of degrading SARS-CoV-2 spike protein. A 2025 patient-reported outcomes study found significant symptom improvement in Long COVID patients using nattokinase
• Bromelain (500 mg daily) disrupts spike protein-ACE2 interactions and reduces inflammation.
• Liposomal Curcumin (500 mg twice daily) shows anti-inflammatory activity and in silico evidence of inhibiting spike protein binding to its receptor.
• NAC (N-acetyl cysteine), CoQ10, and omega-3 fatty acids are supported as mitochondrial and vascular support agents.

It is important to note: no peer-reviewed trial has conclusively demonstrated that any intervention directly removes spike protein from tissue. These approaches are evidence-informed and rational given the proposed mechanisms, but patients should always work with a physician before initiating any protocol, particularly with fibrinolytic agents due to bleeding risk.

Immunomodulation for Neuropathy

For patients with confirmed or suspected Long COVID small fiber neuropathy, the 2025 UT Austin study found that IVIG therapy produced symptomatic improvement in 100% of the small pilot cohort treated. While this was a small sample (n=8), the findings support the autoimmune mechanism and suggest that immunomodulatory therapies may be warranted in appropriate candidates. Referral to a neurologist specializing in post-viral conditions should be considered for patients with refractory neuropathic foot symptom

Podiatric-Specific Interventions at WeTreatFeet

The podiatric management of Long COVID-related foot symptoms requires a different approach than standard foot care. Conventional treatments that work well for typical plantar fasciitis or garden-variety neuropathy may be ineffective in Long COVID patients, whose underlying pathophysiology is distinct.

At WeTreatFeet Podiatry, our approach includes:

1. Comprehensive Vascular and Neurological Assessment
Before initiating any treatment, we conduct thorough lower extremity vascular assessment and neurological evaluation. Understanding whether we are dealing with small fiber neuropathy, vascular compromise, musculoskeletal deconditioning, or a combination of all three changes the entire treatment strategy.

2. Custom Orthotics and Biomechanical Correction
Post-COVID patients often present with gait changes secondary to muscle weakness, pain avoidance patterns, or central sensitization. Custom orthotics address abnormal plantar pressure distribution, reduce compensatory strain, and provide a mechanical foundation that supports rehabilitation.

3. Targeted Physical Therapy Protocols
Standard graded exercise therapy can be counterproductive in Long COVID patients who have post-exertional malaise (PEM). We coordinate with physical therapy using paced, low-intensity protocols focused on lower extremity strengthening, balance rehabilitation, and neuromuscular re-education.

4. Anti-Inflammatory and Neuropathic Pain Management
Topical agents (compounded diclofenac, lidocaine, capsaicin), compression therapy, and in-office procedures are tailored to the patient's specific presentation. For neuropathic symptoms unresponsive to conventional management, we coordinate referral to appropriate specialists.

5. Wound Care and Limb Preservation Vigilance
Diabetic patients with Long COVID represent a particular concern. The combination of pre-existing peripheral neuropathy, compromised microvascular circulation, and the additional vascular insult from COVID creates a dangerous environment for wound development and limb complications. Our wound care and limb preservation teams maintain heightened vigilance for this population.

6. Patient Education and Activity Modification
Understanding that Long COVID symptoms can fluctuate, worsen with activity, and follow a non-linear recovery trajectory is essential for both patients and providers. We spend significant time helping patients understand pacing principles and set realistic recovery expectations.

What to Tell Your Doctor

If you have had COVID-19 and your feet have not been the same since, here is what to bring to your next appointment:

• Timeline: When did foot symptoms start relative to your COVID infection?
• Character of symptoms: Burning, numbness, tingling, aching, swelling, color changes?
• Response to prior treatment: Has anything helped? Has anything made it worse?
• Systemic symptoms: Do you also have fatigue, brain fog, or heart palpitations?
• Prior workup: Have you had nerve conduction studies, skin punch biopsy, or vascular testing?

A skin punch biopsy is the gold standard for diagnosing small fiber neuropathy — and based on current data, it should be considered in any Long COVID patient with persistent lower extremity neuropathic symptoms that do not have another explanation

Our Commitment at WeTreatFeet Podiatry

We have been treating foot pain since before the pandemic, and we will be treating the consequences of COVID long after it fades from the news cycle. The science on Long COVID is evolving rapidly as new studies are being published monthly. At WeTreatFeet, we are committed to staying ahead of it.

If you or someone you know has been living with foot pain, nerve symptoms, or unexplained lower extremity issues since COVID, do not assume it is just aging or "something you have to live with." The evidence suggests there are real, identifiable mechanisms driving these symptoms, and there are meaningful interventions available.

Schedule an appointment at any of our WeTreatFeet Podiatry locations. Our clinical team is trained to evaluate Long COVID-related foot conditions with the nuance this condition demands.

Key Takeaways

• Long COVID affects an estimated 16–17% of people who had COVID-19, totaling tens of millions of Americans
• The SARS-CoV-2 spike protein can persist in tissue for months to years post-infection, driving ongoing inflammation and immune dysregulation
• Fibrinoid microclots form in the blood and resist normal breakdown, impairing microcirculation — particularly in the small vessels of the feet
• 55% of Long COVID patients in one major study reported neuropathic symptoms, with small fiber neuropathy confirmed on biopsy in over half of those tested
• One in four Long COVID neuropathy patients has anti-ganglioside antibodies, suggesting an autoimmune mechanism that persists and drives ongoing nerve damage
• Treatment requires a multi-system approach: vascular support, anti-inflammatory strategies, biomechanical correction, and potentially immunomodulation
• COVID toes, post-COVID plantar fasciitis, peripheral neuropathy, and dysautonomia-related foot symptoms are all documented manifestations requiring specialized podiatric evaluation

This document is intended for educational purposes. It does not constitute medical advice and should not replace consultation with a licensed healthcare provider. WeTreatFeet Podiatry providers are available for evaluation and treatment at our Maryland, Pennsylvania, and Washington DC locations. WeTreatFeet is the leading experts in treating foot related COVID issues. Call 410-363-4343 for an appointtment.