Lets’ Discuss Some Common Foot Problems!
The human body is a very complex and beautiful structure. There’s never a “one answer fits all” when approaching the healing process of an injury/pain. The foot is arguably one of the most complex biomechanical structures in the human body. But, if an injury or pathological process (i.e. arthritis) occurs, the body will recruit other structures to compensate for this limitation, compromising the proper movement/structure of the body. It is when these compensations occur that injury and pain begin.
Pronation (lowering of the arch/rolling-in) and Supination (rising of the arch/rolling-out) are two natural and normal processes in the human foot and are collectively known as your 'foot posture'. Pronation occurs in walking when one foot is weight-bearing and accepting your whole body weight as part of the ‘standing’ phase of the gait cycle. It acts to absorb the forces of stance and return energy, like a spring, to propel you forward. Supination occurs when you push off the toes on one foot, in preparation for transferring the weight to the other foot. Supination forces the foot to act as a rigid lever and efficiently propel you forward while walking. However, when these two actions occur in excessive amounts or become "out-of-sync" with your walking cycle they can become pathological, overloading structures in the foot and ultimately causing pain. If you’re unsure whether you’re over-pronating and over-supinating we do recommend that you seek further consult with a podiatrist to help assess you biomechanics.
Below we will discuss some common pathologies of the lower limb and how they relate to pronation and supination. By understanding the link between the joints and rotational abnormalities of the lower limb, beginning your journey to pain-free walking and better movement will be easier to navigate and further tailored to your specific needs.
The heel is the first point of contact during normal walking and plays a large role in the way the foot functions and sits while weight bearing. The most common places people experience heel pain is under the heel (plantar surface) and at the back of the heel (posterior surface). Heel pain can be caused by many different pathologies or injuries, all of which have overlapping symptoms which makes them hard to differentiate. However, they can have overlapping causes too, which we mentioned earlier, is related to the rotation in the lower body and foot posture.
Plantar fasciitis (fashee-eye-tiss) is one of the most common causes of heel pain under the heel. It is most common in people who are overactive or return to sports after a long period (months or years) of inactivity. Plantar fasciitis can be caused by repetitively stressing or overloading the fascia that runs along the bottom of the foot. Over pronating (arch rolling in) or over supinating (arch rolling out) plays a major roll in the pathological process of plantar fasciitis. Most commonly, pain is felt in the heel (between the bottom of the heel and the beginning of the arch). The pain described is a sharp stabbing or ache. Another area it can be felt is in the inside arch of the foot this is called mid-portion and patients often will feel a sharp pulling/tearing feeling under their arch. Supporting the medial arch of the foot through the use of orthotics may reduce the stress/over-loading of the plantar fascia as they support the natural arch of the foot and aim to minimize pronation/supination.
Achilles Tendonitis (Insertional)
Insertional Achilles tendonitis is the most common cause of heel pain at the back of the heel (posterior aspect) in adolescence and adults. Children and early teens will rarely suffer from this specific pathology as their heel bone has not fully developed and the two growth centers have not fused together yet.
You can develop pathology anywhere along the Achilles tendon, not just the insertion! If your pain is roughly an inch above the back of the heel you may still be experiencing symptoms of Achilles tendonitis, specifically known as mid-portion Achilles tendonitis.
The Achilles tendon is susceptible to both acute and chronic injury. Repetitively stressing and overloading the tendon over long periods of time can lead to chronic Achilles tendonitis. Whereas, a rapid, high stress or overloading of the tendon can cause an acute tear or full rupture of the tendon. The most common cause of Achilles tendonitis is having excessive pronation (rolling in) or supination (rolling out). Orthotics may help with this rotation and therefore de-load the Achilles tendon which may assist in pain reduction and repair.
Calcaneal (heel) Spur
A heel spur is a very common finding on x-ray imaging and can form at the back of the heel at the Achilles insertion or under the heel at the plantar fascial insertion. However, they rarely cause pain on their own! More often than not a patient with heel pain directly under the heel or behind the heel will have a co-existing pathology that causes the pain. These causes are often Plantar fasciitis (under the heel) or Insertional Achilles Tendonitis (behind the heel).
Fun Fact: Any spur that forms in the human body will form at a tendon or ligament insertion! This is because tendons and ligaments under abnormal forces and tension will pull on the bone and tear the small coating (periosteum) away from the bone. The bodies natural response is to calcify the part of the ligament or tendon that connects to the bone, causing a spur to form.
Neural entrapments (under the Heel)
A neural entrapment is when a nerve becomes compressed or pinched between other anatomical structures in the foot. Neural entrapments are quite common but frequently missed as their symptomology is very similar to plantar fasciitis. Two common neural entrapments are Baxter’s nerve entrapment and medial calcaneal nerve entrapment.
Causes of a neural entrapment are; pronated (rolling-in) foot type, and/or co-existing pathologies (heel spurs, plantar fasciitis, muscle hypertrophy of the intrinsic foot muscles or tarsal tunnel syndrome).
Calcaneal (Heel) Fat Pad Syndrome
Believe it or not, the fat under the sole of your foot is extremely important! It’s function and molecular structure is completely different to body fat. It is designed to absorb shock, distribute pressure and protect the internal structures of the foot.
The term fat pad syndrome refers to the inflammation, thinning or displacement of the heel fat pad. This is a fairly common condition in patients who participate in high impact sports or repetitive actions such as running. The health of your collagen and your age can also have a major affect on the fat pad structure.
People with Fat Pad Syndrome will generally feel:
Aching, sometimes burning pain circling around the outside, back and inside of your heel
Pain exponentially worsens with prolonged standing and relieved with sitting/ non-weight-bearing and elevating your feet
You may notice small white lumps that appear around the fat pad while you stand
Painful to walk on hard surfaces
The heel cup in a PolyFab orthotic is designed to support the natural structure of the heel. By having a rounded surface for the heel to sit within it aims to minimize the displacement of the fat pad and may assist in heel pain associated with fat pad syndrome.
Childhood Conditions and Growing Pains
Leg and foot pain in children is often caused by conditions specific to growing and skeletal development. Throughout childhood the bones in the legs and feet grow and fuse at different rates until skeletal maturity is achieved. During the developing years pain can come and go with no real rhyme or reason. Two of the most common childhood conditions are the irritation of the growth plates (most commonly at the back of the heel or front of the knee) from the pulling of tight muscles in active kids. Children generally have a larger degree of mobility in their joints, which when combined with poor muscle control or muscle imbalances can lead to excessive rotation of the legs and feet. Irritation of the growth plate and night pains are specific to children but should also be investigated by your podiatrist when they arise to appropriately diagnosed and treat the condition.
The Forefoot refers to the toes, and ball of your foot. This region is extremely complex and like the ankle very important for normal and efficient ambulation. The type of pain you experience says a lot about the cause of your pain. If you’re experiencing tingling, pins-and-needles, sharp or shooting pain around the ball of your foot then you may be dealing with a nerve irritation. Aching, throbbing or pain in one specific area under the ball of you foot could be related to joint inflammation or swelling, ligament injury or arthritic changes. Relieving forefoot pain will almost always require offloading. PolyFab orthotics support the transverse arch of the foot (arch across the ball of the foot). The aim when supporting he transverse arch is to open up the spaces between the Metatarsals and relieve pressure on the adjacent commonly affected structures such as, nerves, bursa’s, and muscles. It’s also interesting to note that footwear is commonly the cause of forefoot issues if they are too tight, too loose or too stiff!
The knee in a broad sense is a simple joint… yet there is no simple answer for why people have knee pain! The knee functions almost completely as a hinge joint to allow the leg to bend and clear the ground as it moves through the ‘Swing’ phase of the gait cycle. Beyond that, movements of the knee such as internal/external rotation are abnormal and expressed when the body is compensating for a lack of joint range of motion either up-chain (Hip) or down-chain (Ankle). Therefore, the majority of the time it’s safe to say if you have a knee problem, then your also have a hip or ankle problem (with or without pain). The excessive internal/external rotation seen in the thigh, leg and knee force the knee through greater twisting forces and overload a structure that otherwise wouldn’t be. Correcting the foot posture through foot orthotics and correcting the muscular imbalances can assist in reducing the twist on the knee and allow the knee to function in it’s intended way.