Running may seem like a simple to do. However, running is actually a complex movement that puts stress on the ligaments, bones, and joints of the body.  Selecting the correct running shoe is important for increasing performance and avoiding risk of injury.  Running shoes should be selected based on your foot type.  Considerations such as trail versus road shoes are important. Your foot type dictates the degree of cushioning, stability and motion control you require.  The most accurate way to learn your foot type is to visit a local shop that specializes in running shoes.  Professionals can measure your arch type, stride and gait and help you with your shoe needs.

The design of running shoes is created around the idea of pronation.  Pronation is the natural rolling movement of your ankle from the outside to inside when your foot strikes the ground.  If you run properly you strike the ground on the outside of your heel and roll in the direction of your big toe before pushing off once more.  Pronation is beneficial because it assists the lower half of your body in absorbing shock and storing energy.  Those considered neutral runners pronate correctly and do not need running shoes that help correct their form.  Neutral runners can choose from a wide variety of shoes, including barefoot or minimal types.  However, those who have arch problems or who adopt an incorrect form while running may experience too much or too little pronation. They may require running shoes that offer additional support.

Those who overpronate experience an over-abundance of ankle rolling.  Even while standing, those who severely overpronate display ankles that are angled inward.  It is not uncommon for them to have flat feet or curved legs.  The tendency to overpronate may cause many injuries.  Areas that tend to become injured are the knees, ankles, and Achilles tendon.  If you find that you have a tendency to overpronate, you should look at shoes that provide extra stability and motion-control.  Motion-control shoes are straight and firm. Shoes of this type do not curve at the tip.  The restricted flexibility along the middle of the shoe prohibits the foot from rolling too far inward as your foot strikes the ground.

A less common problem is underpronation.  Underpronation, also called supination, is when the feet are unable to roll inward during landing.  Those who underpronate have feet that lack flexibility and high arches.  This prevents any kind of shock absorption, even though it does place less rotational stress on ankles and knees.  This added force can cause fractures, ligament tears, and muscle strains because the legs are trying to compensate for the impact.  Those who underpronate need shoes with more cushioning and flexibility.  If you have a tendency to underpronate, selecting stability or motion-control shoes may cause you more problems by continuing to prevent pronation.

A bunion is an enlargement of the base joint of the toe that connects to the foot, often formed from a bony growth or a patch of swollen tissues. It is caused by the inward shifting of the bones in the big toe, toward the other toes of the foot. This shift can cause a serious amount of pain and discomfort. The area around the big toe can become inflamed, red, and painful.

Bunions are most commonly formed in people who are already genetically predisposed to them or other kinds of bone displacements. Existing bunions can be worsened by wearing improperly fitting shoes. Trying to cram your feet into high heels or running or walking in a way that causes too much stress on the feet can exacerbate bunion development. High heels not only push the big toe inward, but shift one's body weight and center of gravity towards the edge of the feet and toes, expediting bone displacement.

A podiatrist knowledgeable in foot structure and biomechanics will be able to quickly diagnose bunions. Bunions must be distinguished from gout or arthritic conditions, so blood tests may be necessary. The podiatrist may order a radiological exam to provide an image of the bone structure. If the x-ray demonstrates an enlargement of the joint near the base of the toe and a shifting toward the smaller toes, this is indicative of a bunion.

Wearing wider shoes can reduce pressure on the bunion and minimize pain, and high heeled shoes should be eliminated for a period of time. This may be enough to eliminate the pain associated with bunions; however, if pain persists, anti-inflammatory drugs may be prescribed. Severe pain may require an injection of steroids near the bunion. Orthotics for shoes may be prescribed which, by altering the pressure on the foot, can be helpful in reducing pain. These do not correct the problem; but by eliminating the pain, they can provide relief.

For cases that do not respond to these methods of treatment, surgery can be done to reposition the toe. A surgeon may do this by taking out a section of bone or by rearranging the ligaments and tendons in the toe to help keep it properly aligned. It may be necessary even after surgery to wear more comfortable shoes that avoid placing pressure on the toe, as the big toe may move back to its former orientation toward the smaller toes.

Toe pain can originate from corns, calluses, hammertoes, and bunions, as well as ingrown toenails, sprains, fractures, and dislocations. Corns develop as the toe rubs against the inside of a shoe which causes the skin to thicken as a form of protection. A corn is typically cone-shaped and has a small, hardened spot that points inward. When a corn is pressed into the skin, the toe becomes painful. Corns usually form on the top or side of the toe. A callus is also a thickened patch of skin that generally forms on the bottom of the foot. Calluses are the result of friction from the toe rubbing against the inside of a shoe. They may also occur by walking barefoot or having flat feet. A hammertoe is a bump on the knuckle of the second toe that is produced by wearing shoes that are too short for your feet. The bony protrusion rubs against the top of the shoe causing pain and irritation. A bunion is a malformation of the big toe. The base of the big toe pushes away from the smaller toes, forcing the top of the big toe to press toward the other toes. Bunions can be hereditary, or they can result from injury to the toe joint or from wearing high heels with a narrow toe box. The toe becomes inflamed, and a bump may develop at the end of the misplaced bone. Ingrown toenails typically affect the big toe and its surrounding skin. The nail will dig into the skin and become painful. Wearing tight or narrow shoes that compress the big toe causes the nail to grow into the fleshy part of the toe. Cutting toenails incorrectly can also add to the development of an ingrown toenail. A toe sprain originates from a torn or stretched ligament. Strapping the injured toe to the toe next to it for stabilization is common. A broken or fractured toe usually occurs from trauma like dropping a heavy object on it or bumping into something extremely hard and rigid. Osteoporosis, a thinning of the bones, can also bring about toe fractures. 

Any of the conditions mentioned can lead to pain and irritation. While some are more serious than others, seeking an examination and diagnosis from a podiatrist is a good idea. A podiatrist can treat each ailment and get you back on your feet again without pain.