What Causes a Bunion? Although most people view bunions as a bone problem in the foot, in reality most bunions are truly caused by muscular imbalances in the foot. There are several layers of muscles in the foot, I like to use the analogy of sandwich when explaining the muscular foot layers and how imbalance between the layers can lead to a bunion. The first and third layers of foot muscles are the bread layers of the foot. The bread muscles (first and third layers) are called intrinsic muscles, meaning the muscles start and end in the foot and do not travel into the upper leg. These muscles hold the bones of the foot together and give it its shape (posture), just like the bread holds a sandwich together. The second layer of muscle are the long muscles of the foot, they actually start deep in the back of the leg and travel around the ankle and attach to the bottom of the foot. The long muscle of the second layer are very strong and help push our bodies trough locomotion, they are definitely the meat of the sandwich.
Bunions usually form in 4 stages. The first stage may not be very observable, but if you test the strength and function of the intrinsic muscles of the foot (bread muscles) they will be very weak and the balance of the foot will be stable. Over a long period of time if the dysfunctional muscle imbalances are not corrected in the first stage, an actual shifting of the great toe will occur due to the pull of the Flexor Hallucis Longus (meat layer muscle that connects to the tip of the big toe, pointed above by the blue arrow). Because of the orientation of the muscle and its attachment site, it will cause the big toe to move laterally (over to the smaller toes). In a normally functioning foot several of the intrinsic muscles provide adequate opposition to this pull of Flexor Hallucis Longus (ying and yang relationship). But, when the short intrinsic postural muscles are weak and turned off, the long muscle of the foot will over-compensate and structural changes happen. The final and fourth stage is when the prolonged pull gets so great that the actual metatarsal (forefoot bone that connects to the base of the big toe) becomes wedged in the opposite direction, and TA-DHA, you have bunion.
How Can You Help? If you’re young and your balance is poor, or you are starting to see your big toe shifting, find a health care specialist who isn’t just going to tell you to wait a few years and then have surgery. Find an expert to give you a plan to restabilize your foot. If you sprain an ankle, don’t just walk it off, find someone with a strong background in sports medicine and get it checked out and properly rehabbed. Do not encourage your children or grandchildren to walk prematurely before they are ready. And if you are going to wear high heels, don’t walk in them!