296 ‒ Foot health: preventing common injuries, enhancing strength and mobility, & picking footwear

KEYPOINTS

• 01

  The foot is a sensory and mechanical foundation that rehab tends to ignore.

  Conley is a chiropractor and foot and gait specialist who came to feet through years of ballet pain and early work in orthotic labs. The foot has 26 bones and 33 joints in three sections (rearfoot, midfoot, forefoot), plus dense receptors that feed the balance system. Quoting Jay Dicharry, she says 'you can't build a jet engine on a paper airplane.' Clinicians train core, glutes and hips but rarely the foot, our first contact with the ground. Attia compares the feet to a race car's tyres.

• 02

  The heel is built to absorb shock, while the forefoot carries the biggest loads.

  The calcaneus has a spongy core inside a thin cortical shell. Its fat pad has two chambers and, she says, absorbs shock about twice as well as Sorbothane. The forefoot takes about 8 times body weight at push-off in walking. The Achilles takes about 4 times body weight in walking and roughly double that in running, and the inner arch up to 11 times in running. She says the tissues can handle it, but 'if you don't use it you will lose it.'

• 03

  Repeated mild ankle sprains are more harmful than they seem.

  The talus has no muscle attachments, only ligaments. When the lateral ligaments loosen, the talus can shift and cause inner-ankle pain often misdiagnosed as posterior tibialis dysfunction. Ligaments heal; the bigger issue is stretched or torn superficial peroneal nerves and lost sensory input. One of her patients 'couldn't feel anything' by his last sprains.

• 04

  Where a stress fracture occurs tells you how to treat it.

  Compression fractures (heel, fifth metatarsal) come from heavy, rigid landings and need cushioning. Tension fractures (navicular, metatarsals, sesamoids) come from failing to control pronation, so after a boot they need strength rehab. Otherwise the healed bone sits in a weaker foot. Bunions are a midfoot–forefoot instability worsened by narrow shoes (shortened adductor, lengthened abductor). She warns many foot surgeries fail and says 'you don't come out of the womb with a bunion.'

• 05

  Plantar fasciitis usually signals a weak foot.

  The plantar fascia attaches into the deep transverse metatarsal ligament. When the forefoot splays it creates a 'windlass'-like stability signal before push-off, which narrow shoes block. Flexor digitorum brevis shares load with the fascia, and its weakness predicts plantar fasciitis. Orthotics help acutely but, she says, research supports about two weeks to a year, and they need an exit strategy. For chronic plantar fasciosis she relies on loading and strength rather than rest, including shockwave to the medial gastrocnemius. Tendons heal through mechanotransduction: load signals the cells to remodel.

• 06

  She uses specific strength and mobility benchmarks.

  On a toe dynamometer the big toe should press about 10% of body weight and toes 2–5 about 7–8%, without lifting the heel or clawing. In a straight-body wall lean, your toes should let you lean at least 4.5 inches. A single-leg seated calf raise (soleus) should handle about 1.5 times body weight. Attia managed about 1.3 and says almost everyone fails. Ankle dorsiflexion needs about 10° to walk, but she wants about 35°. The big toe needs 40–45° to walk and 65° to sprint.

• 07

  Toe weakness is the single biggest predictor of falls in older adults, she says.

  She cites Karen Mickle's research. Toe strength declines about 35% between 50 and 80. Foot receptors need 20% more pressure by 50 and are about 75% less sensitive by 85. Exercise improves circulation and nerve branching and has improved sensation even in neuropathy. Her fall checks: toe strength, dorsiflexion and inversion/eversion range, single-leg balance (abductor hallucis), and hip control (glute max at heel strike, glute med in mid-stance). She'd screen children's feet the way schools check for scoliosis.

• 08

  Limited ankle dorsiflexion causes problems up the chain.

  The three compensations are early heel rise (more forefoot load), knee hyperextension, and bending forward at the hips (low back pain). If someone can deep-squat while holding a rack, the limit is neurological, not tissue, so they need stability rather than 30 years of calf stretching. Attia notes people under anaesthesia can be stretched far further than awake. Conley says no posture is 'bad' if you can control it and get out of it, and pronation is the first shock absorber.

• 09

  Footwear rules: wide toe box, zero drop, and be careful with cushioning.

  Test the toe box by standing on the shoe's removed insert: if your forefoot spills over, the shoe is too narrow. A wide toe box differs from a wide shoe, and some brands simply add stretchy uppers. Any heel drop is 'a high heel' in her world. More stack height speeds you through pronation. In one study by Sarah Ridge, simply wearing minimal shoes strengthened most foot muscles about as well as an exercise programme. Super shoes (about a 4% advantage) must be 'earned' with hamstring and calf strength.