Check out the picture to the right, this shows the left ankle and foot collapsing inward, this motion is known as pronation or hyperpronatin in this case. This pronation of the foot and ankle can cause twisting of the bones that make up the knee to lead to arthritis, cartilage wearing, and increased stress on the anterior cruciate ligament (ACL) and medial collateral ligament (MCL) in the knee. Repetitive pronation especially when under high forces of running or sudden movements while playing sports can actually weaken those ligaments until they tear completely which is an immediate need for surgery!
In addition, the loss of shock absorbing power in the foot due to this pronation can also increase the shock that the knee, hip, and spine have to absorb which can lead to degeneration in the spine and lower extremity.
How do you know if you have an issue?
1) You may have an issue if you have a history of health conditions such as plantar fasciitis, achilles tendonitis, shin splints, bunions, hammer toes, knee or ankle pain or injury, degeneration or arthritis in the spine or legs, or a history of disc herniation or degenerative disc disease.
2) Stand on your feet and have someone look at your feet and ankles. Do they bow inward or does the achilles tendon bow rather than staying straight up and down? (Reference the picture above for what bowing looks like.)
3) Perform a navicular drop test at home. To do this you'll need an index card and a pen. Sit down and use the pen to draw a dot on the hard bone on the middle of your foot. Place the index card on the inside of your foot and draw a line on the card next to the dot you made on the foot. Stand up and then draw another line where the dot has dropped. If the lines are more than 8mm apart, you have an issue. (check the picture below for what this should look like.)
If you do have an issue, there are a number of great options to help correct pronation and help to reduce your risk of injury or arthritis. In many cases a home exercise and stretching program can strengthen and balance muscles to get rid of pronation all together, however some folks will need additional help with an orthotic to support their arch. Depending on your daily activities and how your body responds to the exercise program, you may need additional support from a custom fitted orthotic that is designed specifically for you. In my office, we have many styles available including orthotics that can be worn in high heels or dress shoes and heavy duty orthotics for those that are on their feet or support additional weight from work equipment (such as firemen or police officers) or from lifting.
If you'd like more information or would like to setup a free consultation, please call my office at 309-689-6200 today.