Big Toe Basics
Let’s talk about one of the most abused joints and least respected in running, the big toe, or hallux. The hallux plays an immensely important role in gait/running, developmentally speaking, our hallux position and function is partially attributed to our ability to run efficiently and helped us out compete other hominids. To avoid putting everyone to sleep, I am going to skip all the biomechanics of the big toe during gait. Let's talk about one of the issues we might have with our big toe. For “normal” gait, we need somewhere between 45-65 degrees of big toe extension with our ankle in neutral. When we don’t have this motion we have either hallux limitus or rigidus. Since hallux rigidus is typically a surgical condition, we will be focusing on hallux limitus.
Hallux limitus is a progressive degenerative condition where the big toe slowly becomes stiffer and more painful. This condition is extremely common among running populations. Hallux limitus is diagnosed any time big toe extension drops below 40 degrees. This is more common in runners with low arches because of the increased amount of force that goes through the base of their great toe and their big toe needs to go through a greater range of motion. The goal of treating hallux limitus is to restore as much motion of the hallux as possible. In conjunction, it is important to also increase range of motion at the ankle. Increased range of motion in both the toe and ankle allow for increased efficiency in walking and running. Toe strength should also be assessed and improved if it is lacking. The minimum requirement for pushing down for the big toe is 10% of your bodyweight, in athletes we really prefer to see this closer to 15 to 20%. This strength helps to control motion of the foot and prevent overuse injuries of not just the big toe but the plantar fascia, foot, and lower extremity as a whole.
Moving into the passive care world, foot orthotics have been shown to have some benefit for individuals with hallux limitus. However, they don’t increase big toe motion, instead, they change how motion is transmitted through the big toe. This does not fix hallux limitus but can be used to decrease symptoms in conjunction with rehabilitation. Another viable option is to wear a shoe with a very stiff midsole or buy a rocker bottom shoe. Both shift the pivot point of the toe off in the gait cycle and can help reduce the amount of force going through the big toe and reduce the range of motion it has to go through. A point about passive care, these do not fix the problem, but can be used to reduce symptoms. Always have proper rehabilitation accompany any passive care.
Our feet take thousands of steps per day and their proper function is of the utmost importance if we are striving to live a long and active life.
