Your feet are the first point of contact with the ground during walking or running, and therefore have to distribute the impact forces of some 180 steps per minute throughout the rest of the lower body. As a result, pain and injury are common woes among distance runners. However, foot numbness, while in many respects the opposite of foot pain, is a common complaint among runners, too.
Morton's Neuroma
A neuroma is a pathological thickening of the tissue surrounding a nerve fiber. When this occurs in the nerve coursing between the third and fourth toes, it's called a Morton's neuroma. Runners who overpronate or have anatomical deformities, such as hammer toes or claw toes, are more likely to end up with a Morton's neuroma. A sign of this condition is both numbness and pain in the third and fourth toes as well as the ball of your foot. Ultrasound treatment may be sufficient to eliminate the problem, and metatarsal pads or custom orthotics may provide relief if ultrasound does not.
Shoe Problems
Running shoes that are too tight or not well suited to the distinct shape of your feet can lead to numbness. Even shoes that fit right may feature a lacing pattern that causes compression of the branch of the peroneal nerve on top of your foot, causing numbness there. On occasion, shoes too tight in the back of the foot can cause numbness in the heel. If you suspect that your shoes are causing your foot numbness, try going up a half-size, changing the lacing pattern on your shoes, or both. Orthotics are of use in some instances.
Tarsal Tunnel Syndrome
Tarsal tunnel syndrome is the lower leg and ankle equivalent of carpal tunnel syndrome of the forearm and hand. Numbness caused by this syndrome is localized to the bottom of your heel due to compression of the posterior tibial nerve. Cysts, bone spurs or other abnormal growths that press on the nerve are the usual suspects implicated in this affliction. Gait abnormalities can also cause tarsal tunnel syndrome. Orthotic shoe inserts, steroid injections and possibly surgery to remove any spurs or cysts are usually effective when taking a few days off from running is not.
Circulatory Problems
Numbness in the foot and elsewhere, running-related or otherwise, usually results from nerve damage or nerve impingement. A decreased blood supply to the foot, however, can also result in a loss of sensation. Diseases such as diabetes and atherosclerosis, or hardening of the arteries, can cause foot numbness during running, as can hypertension. Cigarette smoking and a poor diet, with or without existing disease, contribute to circulatory problems. Running in extreme cold weather can reduce blood flow to the extremities. To rid yourself of this type of numbness, you may need to alter your lifestyle, take prescription drugs or both.
Member Comments