What is the differential diagnosis and management for heel pad pain when weightbearing?

Differential Diagnosis of Heel Pad Pain with Weightbearing

The most common cause of weightbearing heel pad pain is plantar fasciitis, but you must systematically rule out heel pad syndrome (fat pad atrophy), calcaneal stress fracture, nerve entrapment, and less common causes based on pain location and clinical presentation. 1, 2

Differential Diagnosis by Pain Location and Characteristics

Plantar (Bottom) Heel Pain

Plantar Fasciitis (Most Common)

• Pain is medial plantar heel, worst with first steps in morning and after prolonged rest 1, 2
• Tenderness at medial calcaneal tubercle on examination 3
• Pain improves with activity then worsens with continued use 1

Heel Pad Syndrome (Fat Pad Atrophy)

• Deep, bruise-like pain in the middle of the heel (not medial) 1, 2
• Pain directly under the calcaneus with weightbearing 4
• More common in patients >40 years, obese, or with symptoms >12 months 5
• Decreased elasticity and increased thickness of heel fat pad on imaging 5
• Some patients describe a constant "clunk" during footstep 4

Calcaneal Stress Fracture

• Progressively worsening pain following increased activity level or change to harder walking surface 1, 2
• Pain on compression of lateral calcaneus wall, slightly posterior to subtalar joint facet 3
• Swelling and warmth may be present 3
• Radiographs may be initially negative; bone scan confirms diagnosis 3

Nerve Entrapment (Baxter's Nerve or Tarsal Tunnel)

• Pain accompanied by burning, tingling, or numbness 1, 2
• Medial midfoot heel pain with continued weightbearing suggests tarsal tunnel syndrome 1, 2
• Requires EMG and nerve conduction studies for confirmation 3

Posterior Heel Pain

Insertional Achilles Tendinopathy

• Insidious onset with chronic posterior heel pain and swelling 3
• Pain worsens with shoes, improves walking barefoot (opposite of plantar fasciitis) 3
• Prominence and tenderness medial/lateral to Achilles insertion 3
• Radiographs show spurring or erosion at tendon insertion 3

Haglund's Deformity with Retrocalcaneal Bursitis

• Most common in women 20-30 years, but occurs at any age 3
• Acute pain lateral to Achilles tendon with posterior lateral prominence 3
• Pain aggravated by shoes, relieved barefoot 3
• Prominence visible on radiographs 3

Lateral Midfoot Heel Pain

Sinus Tarsi Syndrome

• Lateral midfoot heel pain with feeling of instability 2
• Worsens with increased activity or walking on uneven surfaces 2

Initial Management Algorithm (0-6 Weeks)

Start conservative treatment immediately for all mechanical causes: 3, 6

• Stretching: Calf-muscle and plantar fascia stretching 3-5 times daily 6
• Cryotherapy: Ice through wet towel for 10-minute periods 6
• Footwear: Over-the-counter heel cushions and arch supports; avoid flat shoes and barefoot walking 3, 6
• NSAIDs: For pain relief and inflammation 3, 6
• Activity modification: Limit aggravating activities 6
• Weight loss: If indicated 3, 6
• Padding and strapping: For additional support 3, 6

For insertional Achilles tendinopathy specifically: Open-backed shoes, heel lifts, NO corticosteroid injections near Achilles tendon (rupture risk) 3, 6

If No Improvement After 6 Weeks

Refer to podiatric foot and ankle surgeon while continuing initial treatments 3, 6

Add:

• Customized orthotic devices (moderate benefit at 7-12 weeks only) 6
• Night splinting 3, 6
• Limited corticosteroid injections (appropriate patients only, avoiding Achilles tendon) 3, 6
• Casting or fixed-ankle walker device 3, 6

If No Improvement After 2-3 Months

Continue conservative measures and escalate: 3, 6

• Cast immobilization if not previously used 3, 6
• Consider plantar fasciotomy (surgical) 3, 6
• Extracorporeal shock wave therapy 3, 6
• Explore alternative diagnoses - consider advanced imaging (MRI, ultrasound) to evaluate for heel fat pad pathology, stress fracture, or nerve entrapment 3, 4

Critical Diagnostic Pitfalls

• Heel pad syndrome is often missed: Look for central (not medial) heel pain, age >40, obesity, and prolonged symptoms >12 months 5, 4
• Stress fractures appear normal on initial radiographs: Use bone scan if clinical suspicion high with negative x-rays 3
• Posterior heel pain relieved by barefoot walking indicates Achilles/bursa pathology, NOT plantar fasciitis 3
• Never inject corticosteroids near Achilles tendon insertion - risk of rupture 3, 6
• If neurologic symptoms present (burning, tingling, numbness), refer for EMG/nerve conduction studies early 3, 1

Imaging Recommendations

• Radiographs: First-line for all heel pain to identify fractures, spurs, Haglund deformity 3
• MRI or ultrasound: When diagnosis unclear, to evaluate heel fat pad pathology, stress fractures not visible on x-ray, or soft tissue pathology 3, 4
• Bone scan: For suspected stress fracture with negative radiographs 3
• EMG/nerve conduction studies: For suspected nerve entrapment 3