Toespring is the next deforming shoe feature that is present on most shoes available to consumers, including athletic shoes. Toespring is the elevation of the toebox of the shoe above the supporting surface. Industry standard for most types of shoegear is around 15 degrees. What does this mean?
It means that all the while we are wearing shoes, our toes are being unnaturally elevated above the supporting surface. The reason you should be concerned about this is your toes operate on a system of balanced pulling. There is a balance between tendons pulling on them from the top, bottom and sides. When the toes are artificially elevated from years of shoe wearing, the tendons on the top get a bit of a pulling advantage over the tendons pulling on the bottom and sides of the toes.
This sets up a pulling imbalance that, when coupled with other imbalances such as elevated heels or tapered toeboxes, creates a combination of deformities in the toes referred to as crooked toes, or hammertoes.
This pulling imbalance also contributes to many of the foot problems mentioned in the section above, as well as participating in imbalances created in the lower leg and knee since the muscles that send the tendons to the ends of the toes, take their origin from the lower leg and surrounding structures.
As if these two previously mentioned negative shoe features were not enough of a concern for those concerned about the health of their feet, elevating the heel of the foot by wearing a shoe with an elevated heel further contributes to the unbalanced pull of the tendons going to the toes since the ankle bones, which sit just above the heel, are the points around which the tendons exert some of their pulling to secure the toes on the ground firmly. The toes desperately need to be held firmly against the ground, since the entire body is then going to pass over them during the part of normal foot action called propulsion.
So in case you were not previously concerned with those skin covered bony levers attached to the end of your foot, hopefully you will be now and fit them accordingly and comfortably in a shoe that is shaped as the foot and spread toes are shaped.