by Rebecca Lingerfelt, DPT
You’ve heard that song about how the foot bone’s connected to the leg bone and the leg bone’s connected to the knee bone; well, it’s true! Our bodies are intricately connected and issues in one location can affect other areas of your body in ways you didn’t even realize. Your foot structure has a lot to do with that since we spend so much of our day on our feet through walking or standing, and abnormal foot structure places abnormal stresses on joints further up the body, including the knee, hip, or back. So what kind of feet do YOU have? If you walk barefoot on the beach and look back at your footprints, do you see your whole foot from toe to heel and inside to outside edge, or do you see just your toes to the outside edge of your foot to your heel? The first description is called a flat foot (pes planus), the second is a high arch (pes cavus), and people have varying foot structures between these two extremes.
If you have flat feet, the foot and ankle roll inwards and the foot remains loose when trying to pivot off of it. Because of the inward roll of the ankle, the knee tilts in as well so that a person may appear knock-kneed. This position puts more stress on the inner side of the knee and compresses the outer side. Moving up the chain, the thigh has abnormal rotation and over stretches some hip muscles and shortens others, making it difficult to fully rotate the hips and sit cross-legged on the floor, for example. A person with severely flat feet could benefit from orthotics or stability or motion-control sneakers to hold the foot in better alignment and subsequently improve the alignment of joints further up the leg. Some common injuries with this foot type are shin splints, patellar tracking problems, plantar fasciitis, tendency toward bunion formation, Achilles tendonitis, and a predisposition for ACL injuries.
If you have high arches, the foot stays rigid to properly push off the ground, but it is not a great shock absorber or adapter to uneven ground. Because of the foot not absorbing normal shock while walking, there are more compressive forces traveling up to other joints and could cause long-term arthritis in the knees, hips, or back. The foot’s inability to absorb shock may make this person a good candidate for orthotics that are cushioning and supportive, and they should look for a more neutral or cushioning sneaker. Throughout normal walking and other activity, most of your weight is on the outside edge of the foot, turning the ankles outward and stressing the ankle ligaments. People with this foot type sometimes appear bow-legged or hyper-extended at the knees, excessively stressing the outside and back ligaments of the knee. This person can be at higher risk for ankle sprains, lateral leg tendonitis, hamstring injury, IT band syndrome, and the proximal shock absorption can cause pelvic asymmetry.
It is important to consider how your foot type affects other parts of your body and what you can do to prevent some of the typical injuries. Be smart about choosing footwear that is appropriate for your foot and don’t just choose based on the flashy colors you like. Stretch after your workouts too. And if leg pain still does occur, call us up at Boston Sports Medicine for physical therapy or a custom orthotic evaluation soon!
Dr. Lingerfelt is a Physical Therapist at Boston Sports Medicine