Most of us have been walking since we were anywhere from 9 to 16 months old. We have been doing it for so long that having the ability to stand up and automatically start moving our feet, step by step, is something we take for granted. Time has shown that walking is healthy not only for our physical health, but also for our mental and emotional health.
Arch Function
Recall that one of the fundamental concepts of foot anatomy is that there are three functional arches under each foot, not just one. The medial and lateral longitudinal arches, along with the transverse (metatarsal) arch, form a triangle of stability under each foot. These arches begin forming at age 4 and are fully formed by age 7. The arches are supported by the plantar fascia and the bone-to-bone ligaments. The intrinsic foot muscles do not form the arches.
The three arches and how they are functioning play a huge role in normal / abnormal gait patterns. If the arches are flat, the foot drops to the floor excessively, causing more internal rotation of the tibia / femur / patella than normal. This can cause muscle compensation, and wearing of cartilage and soft tissue in the ankles, knees, hips, and axial spine.
Likewise, people who oversupinate have feet with a high instep that roll outward, creating lateral rotational forces on the tibia / femur / patella. Excessive strain on those joints will then follow, usually felt on the lateral regions. We tend to focus on excessive foot pronation because it is so much more prevalent than excessive supination.
Plantar fasciitis, metatarsalgia, neuromas, Sever's disease, Achilles tendonitis, shin splints, Osgood-Schlatter disease, medial meniscus degeneration, ACL tears, MCL tears, hip arthritis, sacroiliac joint strain, lumbosacral / cervical disc degeneration / arthritis, shoulder stress, headaches and TMJ issues are some of the major conditions patients present with in our clinics that can have a strong causal relationship to the arches of the feet. Since many of us treat these conditions, it's helpful to understand why they could have developed.
If the arches themselves are not in position for healthy function, you can restore optimal balance and alignment with flexible custom orthotics that support all three arches. Unlike over-the-counter insoles with generic correction, custom orthotics are individually designed for each patient to optimize care results, and patient compliance and satisfaction. It's important that the orthotics are provided by a chiropractor who can determine the type of correction needed, and ensure they are fitted and used properly.
Swing and Stance
The swing phase is 40 percent of the gait cycle and is that period of time after toe-off when the leg leaves the ground and is being brought forward to the point just before heel strike. This portion of the gait cycle may offer some insights into hip movements, muscular function and pelvic symmetry. However, this is the non-weight-bearing portion of walking, so biomechanical dysfunction is not always visibly apparent.
The stance phase is 60 percent of the gait cycle and is the weight-bearing portion of gait. Here, we can observe and understand what occurs when the feet and arches function properly and improperly. The stance phase is further broken down into heel strike, foot flat and toe-off stages.
>Heel strike: The initial stage of the stance phase finds the heel striking the ground. The heel is absorbing 30 percent of the 5Gs of shock the calcaneus bone experiences with each heel strike. The force goes from the ground into the hindfoot and we see the foot supinate to provide a counterbalance.
The shockwave hits the calcaneus, then moves up to the talus and spreads across to the cuboid, navicular and cuneiform bones. The medial and lateral longitudinal arches are the prime shock absorbers; custom orthotics provide additional shock absorption to help dissipate the force.
>Foot flat: The middle stage is perhaps the most important in terms of weight-bearing significance. The weight of the body is placed squarely on the foot and all three arches. The tibia and femur bones internally rotate and the patella moves slightly medial to allow the foot to pronate and grip the ground properly. Under normal circumstances, foot flat stresses the foot, arches and plantar fascia, but they all withstand this force and keep the foot balanced and supported. When arch function is compromised, custom orthotics provide additional stance protection.
>Toe-off: The last stage of the stance phase finds the metatarsophalangeal joints dorsiflexing. The foot moves back into supination and the plantar fascia tightens or "springs" the foot back to its normal, non-weight-bearing shape. This stage completes the transfer of weight that began in heel strike and really calls into play the transverse arch, metatarsals and phalanges. Custom orthotics provide additional propulsion to help complete toe-off, fight strain and decrease fatigue.
A Roadmap to Help Patients
The gait cycle is a harmonious symphony of movement when everything works well. But there's the rub: most humans in the world do not have this "normal" gait cycle any longer. Recall earlier when we discussed the three arches being fully formed by age 7. It is at this age people can start to experience problems with their arches that will have lasting, often deleterious effects on the other joints of the body in the years to come.
In my practice, I've observed that 85-87 percent of people pronate excessively or have flat feet. Oversupinators are 3-5 percent and only 10 percent have arches that are supporting their feet adequately (at least for the time being).
For those of you who work on the feet and extremities with regularity, these numbers do not surprise you. Whether a high-level athlete, a desk jockey or a young child, eight of every 10 patients who come to you for care will have excessive foot pronation. Most people have no idea this phenomenon is even happening in their feet and bodies until you point it out to them.
To help the many patients who overpronate, along with the smaller percentage of those who oversupinate, there are three main areas to cover:
- Chiropractic adjustments to the 26 foot bones, as well as the extremities and spine, as indicated.
- Providing custom orthotics: stabilizing, three-arch, flexible foot orthotics align and support all three foot arches and thereby enhance all stages of the stance phase of the gait cycle; and help provide pedal symmetry and foundational alignment for the entire body.
- Prescribing the appropriate exercises for flexibility and strengthening of the intrinsic foot muscles. These exercises will provide secondary support to the foot given that the plantar fascia has already been stretched out.
Clinical Pearls
Understanding and assessing gait cycle does not have to be complicated. It is an extremely valuable tool in examining patients of all ages and activity levels. The information a patient's walking pattern yields is not only useful in a clinical sense, but also can be critical in understanding and treating the patient's ailments.
As chiropractors, we are skilled at finding the cause of the problem and not just chasing symptoms. Utilizing standing posture and gait analysis gives you a birds-eye view of the biomechanical forces at work and provides greater overall knowledge of the person's stress on different joints of the body.
Dr. Kevin Wong, earned a BS in exercise physiology from the University of California – Davis and his DC degree from Palmer Chiropractic College West. He practices in Orinda, Calif., and serves the Lamorinda, Berkeley, Walnut Creek and many other East San Francisco Bay Area communities. He is an expert on foot analysis, walking and standing postures, and orthotics, and lectures nationwide on spinal and extremity adjusting.