Five Foot Problems Caused by Flat Feet

Flat feet are common around the world, and are the source of many foot problems in those who do not walk barefoot from an early age (which is pretty much most of the world). A flattened foot will require the body to adapt somewhat to the added foot flexibility, and will force the body to devote energy to keeping the foot from over-collapsing and making walking strenuous. In turn, many aspects of how a foot is normally supposed to function change, and the foot can develop strains, aches, and even deformity. This article discusses five of the most significant problems that those with flat feet can develop.

1) Heel Pain

Heel pain is the most common foot problem associated with flat feet. As the foot flattens out, the tissues on the bottom of the heel, particularly a rubbery ligament called the plantar fascia, stretches and strains with every step. This is a daily process occurring over a lifetime. Eventually, after the prodding of some minimal injury that most people do not even notice, this strain will gradually cause microscopic tears to occur in the tissue. Ultimately this leads to inflammation of the plantar fascia and other surrounding structures. Arch fatigue will also develop, making it difficult to stand in place or walk for a long period of time. As this strain continues in the heel and arch, the condition worsens and pain will then develop either on the first step of the morning, after a little while of activity, or both. The heel and arch pain can become so intense that not even a supportive shoe is comfortable. Although many people assume this pain is associated with a spur on the heel bone, in reality a bone spur is rarely the cause of pain to the bottom of the heel.

2) Bunions

Bunions are a very complicated deformity of the big toe joint, but are most directly linked to flat feet. Although some people are born with bunions due to a defect in the formation of the long bone connected to the big toe (first metatarsal), most people develop bunions over the course of a long period of time. When someone develops a bunion, the first metatarsal begins a gradual shift toward the inside of the foot in the direction of the opposite foot. Along with this, the bones of the big toe gradually shift towards the second toe as certain parts of the joint tighten and certain parts loosen. The way in which the body has to adjust to walking with a flat foot has a direct effect on the muscle and tissue imbalance that forces these bones to move in the first place. The result is a large bump on the inner side of the foot that rubs against shoes. This bump can get inflamed, and eventually even very wide shoes will still irritate it. Over time, the deformity will wear down the big toe joint itself, leading to arthritis that will cause pain even when one is barefoot.

3) Hammer Toes

Hammer toes develop in a similar manner to bunions. The strain the body must undergo in order to keep a flat foot stable will eventually cause the toes (other than the big toe) to contract upward, forming a hammer toe. Although high arches can also cause hammer toes for another reason altogether, the most common cause is flat feet. As the back of the toes contract upward at the first ‘knuckle’, the ends of the toes contract downward. This leads to toes that have too much pressure on top while in shoes, as well as toes that have too much pressure on the tip of the toe as it is driven downward into the shoe or ground. Corns can develop as the skin tries to protect itself from this increased pressure. The hard skin of the corn can be painful if too thick. Although shoe use usually causes hammer toes to become painful, over time the toe can become painful even with barefoot walking as the joints stiffen and become less flexible. The contraction of the toe can even push the joint of the long bone found at the base of each toe downward, leading to joint inflammation and pain in the ball of the foot.

4) Tendonitis

Flat feet can cause many different parts of the feet to strain. One tendon in particular can strain to the point where it actually degenerates and worsens a flat foot. This tendon is called the posterior tibial tendon, and it is located on the inner side of the foot near the ankle joint. The tendon starts from the muscle of the same name in the leg, and then wraps behind the ankle bone and attaches to a bone on the inner side of the foot. When the foot flattens, the inner side of the foot stretches. This tendon stretches along with it, eventually weakening due to the strain on the tendon fibers. The more the tendon weakens, the more it begins to degenerate. Eventually the tendon becomes frayed and inflamed, causing pain and disability through a process called tendonitis (meaning tendon inflammation). If this process continues over the course of several years, the tendon may degenerate to a state where it is no longer repairable. At that point, it is possible that only a surgical fusion of the foot into the proper position will restore functioning. Not everyone who has flat feet will develop this tendonitis, but flat feet make this tendon damage more likely.

5) Ankle Pain

Pain in the ankle can have a variety of causes. One cause in particular is due to flat feet. As the foot flattens, the outer side of the foot comes into closer contact with the outer side of the ankle. When this occurs, some individuals develop a condition called ‘impingement syndrome’, in which the foot impinges onto the ankle as it flattens out. This can create a range of pain from vague and dull to sharp, felt along the top of the foot near the outer side of the ankle. Due partly to bone and soft tissue compression, the pain can be felt during extended walking or standing. It is usually worse at the end of the day, and can be worsened by floppy or flexible shoes. A nerve in this general region can be irritated by the compression, as well as a cavernous space in a joint found under the ankle joint called the sinus tarsi. This condition is sometimes difficult to identify, as symptoms can be vague and nonspecific to many physicians not well trained in the foot and ankle.

Many of the above problems can be prevented, or in the case of bone deformity, slowed down, with the use of supportive shoes and prescription shoe inserts called orthotics. Store-bought inserts can help, but are ineffective in actually forcing the foot to stay fully in a ‘normal’ position. Surgical reconstruction of the flat foot is an option, but is generally reserved for the relatively small number of people who cannot tolerate orthotics, or those in whom orthotics provided no relief. Treatment is available for all the above conditions when and if they do develop. In the case of painful bunions and hammer toes, surgery is usually necessary unless the symptoms are mild. All the other conditions discussed above can be easily treated without surgery if identified early enough. Proper evaluation by a foot and ankle specialist (podiatrist) can lead to identification and comprehensive treatment of these conditions. Starting the process by visiting one’s family physician can be a start, but generally the services of a specialist are necessary due to the complexity of the flat foot structure and the conditions that follow.