The Science of Plantar Fasciitis & Heel Spurs

Plantar fasciopathy (commonly called plantar fasciitis) is a degenerative condition affecting the plantar fascia origin at the heel bone, characterized by thickening and disorganized collagen structure rather than acute inflammation. The plantar fascia is a thick fibrous band that supports the foot's medial longitudinal arch and acts as a shock absorber during weight-bearing activities. The condition develops when cumulative mechanical stress on the fascia exceeds its adaptive capacity, leading to a failed healing response. This results in small tears, tissue degeneration, and thickening at the calcaneal insertion point. Despite the name "fasciitis," the pathology is primarily degenerative (fasciopathy) rather than inflammatory, similar to other chronic tendon conditions. Contributing factors include sudden increases in weight-bearing activity, biomechanical abnormalities such as limited ankle dorsiflexion from calf tightness, abnormal foot postures (both flat feet and high arches), and weakness in the intrinsic foot muscles. The fascia is particularly vulnerable at its attachment to the heel bone, where mechanical stress concentrates during push-off activities. Plantar fasciopathy often coexists with other lower limb conditions including Achilles tendinopathy and chronic ankle instability, as they share common biomechanical risk factors.