You have read everything on the internet about plantar fasciitis and diligently followed all the advice – ice, medications, stretches, orthotics, and physical therapy, but despite good attention to your foot, ankle, and calf, you’re still not cured. You continue to limit your walking or workouts and any travel plans revolve around how far you think you can walk without pain.
Most risk factors for plantar fasciitis seem straightforward because they seem related to either structural issues (arch or foot deformities, unequal leg lengths) or direct strain on the heel (from overuse and bearing weight).
Although we know we use our whole leg to stand, walk, etc., conventional treatments only focus on unloading the stress on the plantar fascia from the most adjacent areas – the foot and calf. For a significant proportion of recurrent and chronic sufferers, the relief from this localized management is only temporary, even minimal.
This incomplete treatment response suggests that treatment is not adequately addressing the real cause. In my clinical practice, I have often found that these patients suffer with imbalanced leg forces that originate from hypermobile knee joints.
Genu recurvatum (Hypermobile knees, Banana Knees) causes more than just Knee Pain
Knee hyperextension, medically known as genu recurvatum, is when a hypermobile knee joint is able to open beyond ~180 degrees straight until it “locks,” looking like it is bent the wrong way. (See Image)
This backwards pressure on the knee strains the posterior knee joint (cartilage and ligaments), but it also triggers the gastrocnemius (large calf muscle) and hamstrings (posterior thigh muscles) to contract to stabilize the whole leg in this compromised position. (Would you ever build a table with legs like this?) As a result, the quadriceps muscle along the front, middle and side of the thigh is underutilized, which makes it (relatively) stiff and weak.
Depending on individual body proportions and postural habits, visible leg deformities may result such as: bowlegs, knock knees, or internally rotated thighs (kneecaps) and in a variety of combinations, (each leg different). Over time, as the body accumulates the strain of ongoing imbalanced knee mechanics, plantar fasciitis can develop; but pain can also appear anywhere along the leg. When the underlying knee hypermobility is not addressed, therapies aimed only at the foot and calf may help to reduce the heel pain, but seemingly unrelated ankle, knee, or thigh pain can flare up.
I have observed that plantar fasciitis usually affects the side with the more hypermobile knee, and that most people have at least 1 hypermobile knee. (If you are not sure which of your knees is hypermobile, look at old photos of yourself standing and note what knee you are locking backwards. Sometimes you may need to go back to childhood photos.)
In general, the more severe the genu recurvatum, the younger the onset of heel pain and related leg pains. Often, other joints are hypermobile, such as in Joint Hypermobility Syndrome (JHS) or Hypermobility-type Ehlers-Danlos Syndrome (hEDS). Many children with these hypermobility conditions avoid physical activity based on their pain with PE class in school.
Addressing the Root Cause
Unfortunately, despites its pathological mechanics, most joint hypermobility is viewed as a normal variant, and not addressed unless the joint itself is symptomatic and very compromised. But I have found, perhaps because of its size and influential role, that improving the biomechanics of any degree of knee hypermobility greatly impacts heel pain, and even other problems such as dysmenorrhea (painful periods), low back pain, TMJ disorder, and vertigo.
These results are possible because our fascia, the continuous sheath of connective tissue that encases and connects our muscles, also encases our organs. Like our bones, fascia is constantly remodeling to adapt to the physical stresses of our daily movement patterns, so that with thoughtful reeducation, whole body function can still improve even after decades of misalignment. Research is suggesting that fascia is more than just structural support to our muscles and bones; it may be its own independently functioning organ. Fascia could then provide the missing piece in our understanding of how significant joint hypermobility could be associated with symptoms of many other body systems: digestive, respiratory, cardiac, genitourinary, and neurologic.