Heel Pad Syndrome

Heel Pad Syndrome (Heel Fat Pad Syndrome)

Introduction

Heel Pad Syndrome (or Heel Fat Pad Syndrome, HFPS) is a frequently overlooked but significant cause of heel pain. The heel’s fat pad serves a critical role in absorbing shock and distributing pressure during movement. When compromised—due to thinning, injury, or atrophy—it can lead to persistent, sometimes debilitating pain in the heel. While plantar fasciitis is the most common cause of heel pain, research suggests that HFPS may be the second most prevalent source.

What Is the Heel Fat Pad?

The heel fat pad is a specialized cushion located beneath the heel bone (calcaneus). It is made up of dense fibrous septa that compartmentalize fat cells into microchambers—these structures act as shock absorbers. With each step, especially during high-impact activities such as running or jumping, the fat pad absorbs a portion of the body’s weight—up to 250% during running.

With age, repetitive stress, obesity, or certain medical conditions, the heel pad can deteriorate. This degeneration reduces its ability to cushion the heel, leading to HFPS. Understanding this anatomical structure is critical for appreciating the role it plays in heel pain.

Causes and Risk Factors

Several risk factors have been proposed in the development of HFPS. These include:

  • Aging – Natural degeneration of collagen and elastin in the fat pad.
  • Overuse – Common in long-distance runners, athletes, or people with occupations that involve prolonged standing.
  • Improper footwear – Shoes lacking heel support can stress the heel fat pad.
  • Steroid injections – Repeated corticosteroid use in the heel can thin the fat pad.
  • Comorbidities – Conditions such as diabetes and rheumatoid arthritis may impair fat pad integrity.

A traumatic event, such as landing hard on the heel or repetitive microtrauma from poor biomechanics, may also lead to acute or chronic HFPS.

Symptoms

Patients with HFPS typically report:

  • Deep, bruise-like pain in the center or sides of the heel.
  • Pain that worsens when walking barefoot or on hard surfaces.
  • Discomfort that intensifies with prolonged standing.
  • Pain that can be present at night or bilaterally (in both heels), unlike plantar fasciitis.
  • Absence of first-step pain in the morning, which is a hallmark of plantar fasciitis.

Diagnosis

Diagnosing HFPS can be challenging, especially since it often coexists with or is mistaken for plantar fasciitis. Diagnosis is made based on:

  1. Clinical examination – Tenderness localized in the heel pad rather than the plantar fascia’s attachment.
  2. Ultrasound – Measures heel pad thickness; a value below 9 mm is often suggestive of HFPS.
  3. MRI – Detects fat pad atrophy, fibrosis, edema, and septal ruptures.

 

Imaging: What It Shows

Ultrasound

  • Reveals atrophy, loss of compressibility, and septa disruption (seen as free tissue or fluid between chambers).
  • Dynamic ultrasound can also detect hypermobility in the fat pad during heel compression.

MRI

  • Highlights fibrosis (bands of scar tissue) and edema.
  • More sensitive in detecting subtle tissue changes compared to ultrasound.
  • Can detect septa ruptures and pseudocystic formations, often in athletes with history of heel trauma.

Prevalence and Epidemiology

A population-based study from the U.S. revealed a 4.2% prevalence of HFPS among older adults, compared to 6.9% for plantar fasciitis. A South Korean study found that among patients with heel pain, 15% were diagnosed with HFPS, while 53% had plantar fasciitis.

Given these numbers, HFPS is likely the second most common cause of heel pain, yet it remains underdiagnosed and under-researched.

Treatment Options

Despite its prevalence, no randomized controlled trials (RCTs) exist that evaluate the effectiveness of conservative HFPS treatments. Still, some strategies are commonly used:

Conservative Management

  • Viscoelastic heel cups – Silicone or gel heel inserts help absorb shock and reduce stress on the fat pad.
  • Low-dye arch taping – Stabilizes the foot and may reduce heel pad displacement.
  • Footwear modification – Supportive, cushioned shoes can greatly help.
  • Activity modification – Avoiding high-impact activity, especially barefoot walking.

A quasi-experimental study found that low-dye taping reduced pain by up to 3 points on a 10-point pain scale and reduced plantar pressure during walking. Another case report showed that heel pad stiffness decreased after use of gel heel cups over 3 months, with significant pain reduction.

Experimental and Surgical Options

In rare cases, Platelet-Rich Plasma (PRP) injections or surgical correction (such as removal of damaged tissue and fat pad reconstruction) have been used. One case in the Balius et al. study required surgical repair, which helped the patient return to activity, albeit with some residual discomfort.

Final Thoughts

Heel Pad Syndrome is a significant, under-recognized contributor to chronic heel pain. While it shares symptoms with plantar fasciitis, it is a distinct clinical entity that requires a different diagnostic and treatment approach. Patients suffering from persistent heel discomfort—especially those who do not respond to standard plantar fasciitis treatments—should be evaluated for HFPS.

Takeaway for Patients:

If your heel pain worsens while standing or walking barefoot on hard surfaces and isn’t relieved by typical plantar fasciitis treatments, HFPS may be the cause. Seek out a foot and ankle specialist familiar with fat pad pathology for thorough evaluation.