Plantar heel pain and foot loading during normal walking

Area of Science:

• Biomechanics
• Orthopedics
• Sports Medicine

Background:

• Plantar heel pain is common and aggravated by weight-bearing.
• Understanding foot loading mechanics in plantar heel pain is crucial for developing effective interventions.
• Limited evidence exists on how individuals with heel pain load their feet during gait.

Purpose of the Study:

• To investigate and compare plantar pressure and loading patterns during walking in individuals with plantar heel pain versus asymptomatic controls.
• To explore the relationship between pain severity and foot loading characteristics in plantar heel pain.
• To elucidate compensatory strategies employed by individuals with plantar heel pain during gait.

Main Methods:

• Plantar pressure data were collected using the Emed-AT platform during normal walking in 198 individuals with plantar heel pain and 70 controls.
• Measurements included maximum force, force-time integral, peak pressure, pressure-time integral, and contact time across heel, midfoot, and forefoot regions.
• Participants with heel pain were categorized into low-pain and high-pain groups based on the Foot Health Status Questionnaire pain score for further analysis.

Main Results:

• The plantar heel pain group exhibited reduced maximum force under the heel and medial forefoot, and lower peak pressure under the posterolateral heel compared to controls.
• Force-time integrals were decreased in posterior heel regions and increased in the lateral forefoot for the heel pain group.
• Individuals with higher pain levels showed lower peak pressure and maximum force under the heel.
• Midfoot and forefoot contact times were prolonged in the plantar heel pain group.

Conclusions:

• Individuals with plantar heel pain demonstrate altered foot loading patterns during walking, characterized by reduced heel loading and modified forefoot loading.
• These loading modifications appear to be a compensatory strategy to offload the painful heel.
• Pain severity correlates with reduced peak pressure and force absorption in the heel, further supporting a pain-avoidance mechanism.