Can plantar fasciitis be unilateral?

Plantar Fasciitis Can Present Unilaterally

Yes, plantar fasciitis commonly presents as a unilateral condition, affecting only one foot, though it can also occur bilaterally in some patients 1.

Clinical Presentation of Plantar Fasciitis

Plantar fasciitis typically presents with the following characteristics:

• Pain localized to the inferior heel, particularly at the medial calcaneal tubercle where the plantar fascia originates
• Pain that is most severe with the first few steps in the morning or after periods of rest (classic presentation) 2
• Discomfort that may worsen with prolonged standing or walking
• Pain that can be unilateral (one foot) or bilateral (both feet)

Diagnostic Considerations

When evaluating a patient with suspected plantar fasciitis:

• Radiography is typically the initial imaging study for painful heel, though it has limited sensitivity for fasciitis itself 1
• Weightbearing radiographs can be helpful - the combination of thickened plantar fascia and fat pad abnormalities on radiographs has a sensitivity of 85% and specificity of 95% for plantar fasciitis 1
• Ultrasound is useful for evaluating the plantar fascia when there is high clinical suspicion 1
• MRI may be considered for cases where the diagnosis remains uncertain or to rule out other causes of heel pain

Unilateral vs. Bilateral Presentation

While the evidence provided doesn't explicitly state the prevalence of unilateral versus bilateral plantar fasciitis, clinical practice recognizes that:

• Unilateral presentation is common and may be related to:

  • Biomechanical abnormalities affecting one foot
  • Activity patterns that place more stress on one foot
  • Previous injury to one foot
  • Differences in footwear fit or wear patterns

• Factors that may contribute to plantar fasciitis include:

  • Obesity
  • Prolonged standing or walking
  • Running
  • Biomechanical abnormalities (tight Achilles tendon, pes cavus, pes planus) 3
  • Middle age (most common in adults aged 40-70 years) 4

Treatment Approach

Treatment for plantar fasciitis, whether unilateral or bilateral, typically includes:

• Conservative measures (effective in approximately 90% of patients) 3:

  • Plantar fascia-specific stretching and calf stretching
  • Appropriate orthotics
  • Night dorsiflexion splinting
  • Activity modification to decrease repetitive loading
  • Nonsteroidal anti-inflammatory drugs

• For recalcitrant cases:

  • Corticosteroid injections (noting risks of fat pad atrophy and fascia rupture) 5
  • Extracorporeal shock wave therapy for chronic cases 5

Important Clinical Considerations

• The diagnosis of plantar fasciitis is primarily clinical and can usually be established through history and physical examination
• Treatment should begin promptly, as shorter intervals between symptom onset and treatment initiation are associated with faster resolution 2
• Even when unilateral, attention should be paid to proper footwear and biomechanics for both feet to prevent development in the contralateral foot

In summary, plantar fasciitis commonly presents as a unilateral condition, though it can affect both feet. The unilateral presentation does not change the fundamental approach to diagnosis and management.