Plantar fasciitis is one of the most common causes of heel pain in adults, affecting roughly 10% of people at some point in their lives. Bunions (hallux valgus) affect up to 23% of adults aged 18–65. Neither condition is common in populations that don’t wear shoes. That’s not a coincidence — it’s evolutionary medicine at work.
The foot that walking upright built
The human foot is a remarkable evolutionary achievement. The longitudinal arch — unique among primates — acts as a spring, storing and releasing energy with each step. The plantar fascia is the tensioning cable that maintains this arch. When load, gait mechanics, or footwear alter the way this spring system functions, the plantar fascia is placed under abnormal stress. Micro-tears accumulate at its calcaneal insertion. The result is the searing morning pain of plantar fasciitis.
Bunions tell a similar story. The foot evolved to spread and grip — the big toe plays a critical role in propulsion and balance. Narrow-toed footwear compresses the forefoot, deflecting the hallux medially over years and decades. The bony deformity is the skeleton adapting to a constraint it was never designed for.
Flat, hard surfaces and the modern shoe
The human foot evolved on varied, yielding, natural terrain — not on concrete, tarmac, or polished floors. It also evolved without the rigid sole, elevated heel, and constrained toe box of modern footwear. Conventional shoes alter every aspect of how the foot loads, propels, and recovers: they shorten the Achilles tendon complex, reduce intrinsic foot muscle strength, narrow the toe spread, and shift load distribution in ways the plantar fascia was not designed to handle continuously.
What this means at OQ
At OQ, foot and lower limb symptoms are assessed in the context of the whole kinetic chain. Associate osteopath Sota Omura has specific expertise in gait analysis and orthotics (insoles), addressing how load distributes from the foot through the ankle, knee, hip, and lumbar spine. Understanding the evolutionary design of the foot — and how modern footwear and surfaces violate that design — is central to how we approach plantar fasciitis, bunions, and related conditions.
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