Heel pain or foot pain can be one of the most debilitating conditions for an individual. We are designed to operate in a bipedal state. Whether we are standing, walking, running, or jumping, we are meant to be on our feet. But what happens when we experience heel or foot pain and we can’t tolerate these activities?
Often blamed is the plantar fascia, the broad triangular connective tissue, anchored at the medial aspect of the calcaneus (heel) that spans down to the toes. Its role is to act as our first shock absorber that dissipates ground reaction forces as we move throughout our environment. It secures the infrastructure of the foot by supporting the medial longitudinal arch, making it an essential feature for optimal foot health. But I am here to tell you, plantar fasciitis, is not just a foot issue. Actually, it rarely is. Only about five percent of cases don’t resolve conservatively and require surgical intervention.
The plantar fascia plays a big role in our gait efficiency, but so does our pelvis and thorax. Do these structures function independently of each other? No, but they do influence one another. Our proximal dysfunction can actually drive our foot symptoms. We tend to hurt at our weakest point and not at the point of dysfunction. This is where most treatments are lost. It hurts at “X” so let me rub and massage “X.” Treatment becomes myopically focused on tissue/structure and “damage” rather than addressing the underlying mechanism.
We need to understand pain isn’t bad and it doesn’t necessarily equate to the degree of tissue damage. Pain is a perceptual response to a threat. It protects our bodies by telling us something isn’t right and we need to change a behavior to reduce said threat.
Now this doesn’t mean we ignore the foot or negate manual therapy application. It means there has to be an appreciation for the interconnected nature of our body to guide intervention.
This is why it is important we take a step back from the typical local perspective and appreciate the global perspective that yields a lot more as we recognize both intrinsic and extrinsic risk factors for plantar fasciitis.
It starts at a societal level. Today is all about being able to do more, when in reality we don’t have the capacity to do so. We, as a people don’t know how to handle more because we don’t have effective stress management strategies. The literature is reporting the highest levels of chronic stress, fatigue, and anxiety and with this comes more chronic flight/fight, or sympathetic nervous system activity. This is the same part of the nervous system that becomes active when we experience pain. Coincidence? I don't think so. Our bodies can't distinguish between stressors. They simply interpret and react to ensure survival. First order of importance when stressed, shift metabolic resources and assume a survival posture. It is this stress response though that influences the intrinsic risk factors associated with plantar fasciitis: big toe mobility, ankle dorsiflexion, calf muscle “tightness”, and hip motor control.
As our posture changes to a more extended form, we will see backs that are over extended, rib cages elevated, pelvic girdles dropped forward, and calves with an increase in tone. All of this will inherently limit our movement variability and subsequently overload our feet each step we take. This survival posture, thus increases the metabolic demand of the plantar fascia. It alters the function of the big toe and ultimately the windlass mechanism, which is crucial in preventing our arch from collapsing during the mid-stance of gait. As we achieve a mid-stance position, our plantar fascia tightens thereby pulling the big toe into extension and enhancing ankle dorsiflexion. When efficient, it will prevent excessive foot pronation (arch collapse), which is present in 81-86% of plantar fasciitis cases. It truly is a chain effect.
The chain continues as we move up to the hip. Our motor control of the mid-stance position is a reflection of foot and hip integration. However control becomes increasingly difficult the longer we remain overly extended. This posture poorly positions hip musculature and unfortunately sets the stage for compensation at the first opportunity, the foot. Our foot is not only the first intimate interaction with the environment, it is our first chance to respond to it. However, if we don’t have the proximal orientation of the hip and pelvis, we can’t expect our foot to respond efficiently. Don’t believe the hip has an influence? Try this. Stand-up without shoes and watch what happens when we squeeze/tighten our butt. THE ARCHES LIFT! Every bad foot can be controlled by a good hip. Our hips and pelvis have a powerful influence over our feet and must not be neglected in the rehabilitation process.
So here is the relevance of this matter.
Currently 10% of the general population will develop plantar fasciitis in their lifetime and it will most often occur during occupational years. Given that these years have proven to be the most stressful, we will be more prone to living our lives in a survival posture and thereby overloading our feet. If left unchecked, we could miss work, lose out on wages, or experience a reduction in work productivity. Outside of our work field, it could generate fear-avoidance behaviors to avoid the pain experience. In turn, we reinforce bad behavioral choices and potentially elevate our stress. Now we are in a pain-cycle searching for a way out.
The way out of this cycle is not only addressing the aforementioned intrinsic risk factors through position, but also by addressing our extrinsic risk factors.
As mentioned earlier, pain is an indication we need to have a behavioral change, most notably our extrinsic factors: poor footwear, prolonged occupational weight bearing, and large increases in activity level.
All extrinsic factors are easily modifiable, but usually hard to adhere too, especially when it comes to our footwear. Poor unsupported footwear such as; heels, sandals, flats, and some work boots don’t provide enough sensory input and end up reinforcing poor intrinsic factor development. Despite knowing the benefits of footwear, people still struggle for various reasons: work, financial, etc. This is why orthotics are often sought after by the public. Belief is that an orthotic can be the fix for poor footwear. This may or may not be the case, but regardless it shouldn’t be the first line. Establishment of an effective home exercise program has been shown to be just as effective when addressing the underlying mechanisms. This should be our first line.
The physical stress of being on our feet also cannot be overlooked, which is why prolonged occupational weight bearing is a risk factor that needs to be considered. If we are on our feet 40+ hours week for 20 or 30 years straight, we are accumulating a lot foot stress. Research shows walking just one mile a foot can endure nearly 60 tons of stress. We need to have efficient foot posture and mechanics to withstand this amount of stress over the long haul.
Relating to tissue overload, large increases in our activity level can also increase our susceptibility to plantar fasciitis. Although our bodies are adaptable they are more concerned with survival. So if we make too large of a jump in our exercise regimen, intensity or duration, our body will let us know. Thus, a strategic application of physical activity to control the purposeful stress of exercise is needed to allow the body to best adapt without any repercussions.
So to recap, plantar fasciitis is not just a foot issue. It is a multifactorial issue that demands respect of the body’s natural design. Proximal dysfunction is most likely the offender and the foot the victim. The success of treatment hangs on the ability to identify and address all intrinsic and extrinsic factors that are working against our feet. And the good news? Most of these risk factors are modifiable. We are in control.
Stay Well,
Keaton
References:
Ratey JJ. Spark, The Revolutionary New Science of Exercise and the Brain. Little, Brown; 2013.
Rathleff MS, Mølgaard CM, Fredberg U, et al. High-load strength training improves outcome in patients with plantar fasciitis: A randomized controlled trial with 12-month follow-up. Scand J Med Sci Sports. 2015;25(3):e292-300.
Sapolsky RM. Why Zebras Don't Get Ulcers, An Updated Guide to Stress, Stress-related Diseases, and Coping. 2004.
Tahririan MA, Motififard M, Tahmasebi MN, Siavashi B. Plantar fasciitis. J Res Med Sci. 2012;17(8):799-804.
Thompson JV, Saini SS, Reb CW, Daniel JN. Diagnosis and management of plantar fasciitis. J Am Osteopath Assoc. 2014;114(12):900-6.