Stress fractures are caused by repetitive mechanical forces applied to a bone during activities such as walking or running. The magnitude of the forces seen during these activities exceed the amount the metatarsal bones are designed to endure which leads to microscopic fracture patterns.

The frequency of fracture distribution from most to least common is 2nd, 3rd, 4th, 5th, and finally 1st metatarsal. This distribution is primarily caused by the first metatarsal not properly carrying the majority of the walking load as it is designed to do. The transfer of load away from the 1st metatarsal leads the others to carry loads past their failure point. Faulty foot biomechanics, loss of bone density, or overuse conditions such poor training techniques are all factors that fatigue the metatarsals to the point of failure.

Stress fractures to the metatarsals are not as uncommon as you might think. The rise in popularity in minimalist shoes offering “light and flexible” construction has created an increase in people seeing practitioners for this avoidable condition.

Typically, this specific style of shoe is promoted by using phrases like “close to the ground feel” or “barefoot-style” and should be warning signs for some. These minimalist shoes are designed with very specific conditions in mind that when exceeded can lead to injury.

Factors that can lead to injuries while using minimalist include:
• Constant use on hard surfaces such as concrete
• Excessively over pronating or supinating while walking or running
• User weighing past the range the shoe is designed to carry
• Minimal cushioning to the forefoot area
• Shoe midsole foam with inadequate shock absorption

Minimalist shoes are not for everyone and their improper use is a major cause of metatarsal stress fractures. Finding the right shoe for your body style (small vs. large body frame), level of daily activity (casual walker vs. intense runner), and surroundings (trails vs. concrete) is essential to your health.