Conditions affecting the foot are the 2nd most common site for running related injuries. These issues range from plantar fasciitis, metatarsalgia, to stress fractures. In my time focusing on runners, I have worked with all these conditions. Interestingly, it is not uncommon for patients to come to me after having unsuccessfully managed their pain with various doctors, podiatrists, orthotics and injections.
Why would PT be the last resort? Usually people do not know their feet are malleable. Feet, like people, have so much potential to change with manual therapy and exercise. I contend physical therapy should be a first stop for runners who develop metatarsalgia from movement related activities, like running. It is my hope to impart some wisdom on this issue and how a physical therapist can help.
Metatarsalgia is a painful condition of the ball of the foot. It is a broad term referencing pain affecting the bones, joints, and nerves. The foot can be divided into 3 sections: the rearfoot, midfoot and forefoot. The forefoot is frequently referred to as the ball of the foot. Anatomically, it consists of the metatarsal and phalangeal bones, the metatarsal-phalangeal joints, the phalangeal joints, the plantar fat pad, muscles, tendons, arteries, veins and nerves.
In walking and running, the foot must absorb force then be capable of acting like a spring to propel us forward. Throughout the gait cycle, the muscles in the foot and leg work to prevent excessive foot and arch motion.
Optimal movement begins with landing on the outer point of the heel. The center of pressure then moves along the outside portion of the mid-to-forefoot. Next, the foot pronates to connect the big toe to the ground. It is at this point that the muscles of the foot and leg stabilize the body and absorb the ground forces. As we move into the push-off phase of walking/running, the weight shifts to the ball of the foot ,primarily underneath the ball of the 1st and 2nd toes. The foot acts like a catapult to propel us forward.
Clinically, I will see three common dysfunctions affecting this optimal movement: limited ankle mobility, poor toe dexterity, and absent coordination of the hip. I will detail how each of these issues cause inefficient movement that yields excessive stress onto the ball of the foot.
Ankle dorsiflexion is a movement that occurs to allow the leg to move over the foot. If the ankle does not flex, more pressure is placed on the ball of the foot. This would be like tip-toeing around all the time.
Improving this movement involves massaging and stretching the muscles of the leg and the foot, as well as mobilizing the joint of the ankle.
Toe dexterity refers to the coordination and strength of the toe muscles. It is not always necessary to be able to have isolated control of each toe for function, but exercising these muscles teaches people how to position their arches and how to press the big toe into the ground. The big toe is essential in anchoring the foot into the ground. If it does not, the foot will excessively pronate often leading to rolling over the inside portion of the big toe, diverting pressure to the middle of the forefoot or both.
A recent study in experienced runners looked at the effectiveness of toe dexterity exercises. Runners learned simple exercises from physical therapists then were followed over the course of a year to track injuries. Another group of runners were instructed in only stretching. The authors found those who only stretched were 2.42 times more likely to sustain a running injury. Thus they concluded the stronger the foot the more resilient the runner.
The hip effects the foot! When the pelvis or the hip cannot maintain their position, the pelvis drops and the thigh bone moves inward. This movement at the hip will causes the foot to over-pronate. It is here we can appreciate the interconnectedness of the body.
The hip will move this way when it lacks strength and coordination. Restoring pelvis positioning will differ on a case by case basis depending on a person’s level of control and pain sensitivity. The range of exercises may begin with core work in the form of a dead bug, bird dog and a bridge. It can be progressed to basic movements like a squat or a step up. It can be challenged further through single leg movements to work on maintaining the limb’s alignment. Lastly, it must be reloaded to meet the demands of running or walking through resistance training, jumping or the activity itself.
Foot issues are difficult to manage on your own. It is helpful to work alongside a physical therapist who understands running and works with people who have foot problems. When pain leads to forced time off, interference with sleep or altered movement (like limping) then it is time to seek professional assistance. Don’t guess, get assessed!
References:
Tauton, J et al. A retrospective case-control analysis of 2002 running injuries. 2002. BJSM. https://pubmed.ncbi.nlm.nih.gov/11916889/
Headlee. Fatigue of the plantar intrinsic foot muscles increases navicular drop. 2008. J Electromyogr Kinesiol. https://pubmed.ncbi.nlm.nih.gov/17208458/
Aronow. The effect of triceps surae contracture force on plantar foot pressure distribution. 2006. Foot Ankle Int. https://pubmed.ncbi.nlm.nih.gov/16442028/
Taddei U. Effects of a foot strengthening program on foot muscle morphology and running mechanics: A proof-of-concept, single-blind randomized controlled trial. 2020. Phys Ther Sport. https://pubmed.ncbi.nlm.nih.gov/31962191/