Flat feet (also known as pes planus or fallen arches) is a condition whereby the entire soles of the feet touch the ground when in a standing position.
Under the foot is an upward curve called an arch. The longitudinal arch runs through the length of the foot while the transverse arch runs across the foot. The arch is held up by the attachment of the muscles to the bones by the tendons.
A lot of factors can lead to fallen feet. Some of them are environmental while some are genetic. Flat feet due to genetics can last for a lifetime while flat feet due to environmental factors can occur towards old age.
Some causes of flat feet are genetics, injuries like torn tendons, rheumatoid arthritis, obesity, diabetes, pregnancy, high blood pressure, and old age.
When the soft tissue supporting the arch gets weaker it tends to fall, and this is known as posterior tibial tendon dysfunction.
Causes of Flat Feet
There are different causes of flat feet. Some are congenital (present at birth) while some are acquired. Some of the common causes of flat feet are
This is a process of transferring traits from one generation to the next. Studies have shown that genetics can play a very significant role in the development of flat feet. At birth, defects like vertical talus might be present and it leads to rigid flat feet.
Later in childhood, other feet defects like the tarsal coalition might be detected and can also lead to flat feet.
This is a deformity of the foot and it is rare. It is congenital (present at birth) and it can occur on one foot or on both feet.
It is usually painless for the baby, but it can lead to discomfort or disability as the baby gets older.
The talus is a tiny bone that is positioned between the calcaneus (heel bone) and the two major bones of the leg, the fibula, and tibia. The talus connects the foot with the legs and helps in bearing the weight of the body.
In congenital vertical talus, the bone forms in a wrong position and other bones that are normally in front of the talus shifts above it.
As a result of this, the foot will point upwards and the bottom of the foot becomes stiff. Most times, the arch of the foot curves outwards in a condition known as overpronation.
There are 7 bones that make up the tarsals (mid and hindfoot). They help in movement and the bearing of the body weight. These bones are the talus, cuboid, navicular, calcaneus, middle cuneiform, medial cuneiform, and lateral cuneiform.
These bones form flexible joints, but a tarsal coalition occurs when a fibrous tissue or bone cartilage grows on these joints and they stiffen.
This rigidity causes a lot of pain and discomfort and might reduce movement or prevent movement completely.
There are two types of tarsal coalition. They are the calcaneonavicular coalition (CN bar) and the talocalcaneal coalition (TC bar).
The calcaneonavicular coalition occurs when the fibrous tissue or cartilage grows between the calcaneus and talus bone.
The talocalcaneal coalition occurs when the growth occurs between the talus and calcaneus bone.
Tarsal coalition can occur on a foot or both feet. The cause of the tarsal coalition is believed to be a genetic error during the division of the embryonic cells responsible for the formation of the tarsals.
Posterior Tibial Tendon Dysfunction
A muscle is attached to a bone by tendons. The posterior tendons attach the calf muscles to the bones of the hindfoot.
Posterior tibial tendon dysfunction occurs when the tendon that holds the posterior tibial muscles to the feet bones becomes inflamed or torn. This condition also occurs when the joints and ligaments on the inner foot collapse.
The posterior tibial tendon is one of the most useful foot tendons. It helps to hold up the arch and support the foot during movements.
Posterior tibial tendon dysfunction is characterized by pain on the ankles and heels, difficulty in walking, malalignment of the bones and eventual deformity.
This is an autoimmune disease that occurs when the immune mistakenly starts to attack the body tissues. This disease does not only cause inflammation of the joints, but can also affect the heart, lungs, eyes, skin, and even blood vessels.
Rheumatoid arthritis causes a painful swelling that results in bone erosion and eventual deformity.
Cartilages (elastic semi-hard tissue that pad the joints) protects the joints from friction with each other. Rheumatic arthritis breaks down the cartilages slowly and increases the friction between the joints.
This friction leads to inflammation of the joints and damage of the tissues surrounding the joints. This makes the joint weak and unable to bear the body weight properly.
The parts of the body commonly affected by rheumatoid arthritis are the heel, the midfoot, the toes, and the bones below the ankle.
This is a group of disorders, present at birth, that affects the ability to move, balance and maintain a posture.
Foot deformities are associated with cerebral palsy. The most common types of foot deformities that occur in this condition are Pes Planovalgus (flat feet), Equinovarus (club foot), Pes Cavus (high arch), Equinovalgus (plantarflexed feet), and Hallux valgus (bunion toes).
Disadvantages of Flat Feet
The problems associated with flat feet are:
Poor Shock Absorption
The lowering of the arch during movement absorbs the shock exerted on the foot by the body weight. Fallen arches or flat feet do not absorb shock rather the force generated by the impact of the body is transferred to the back and hips.
This leads to the pain on the ankles, knees, hips and back.
This is the inflammation of the plantar fascia which is the thick tissue under the foot that joins the heel bones to the toes.
Symptoms of plantar fasciitis are heel pain, foot tingling, pain after prolonged rest, and heel tenderness,
Diagnosis of Flat Feet
Finding out if one has flat feet can be done personally unless investigations are required to find out the cause. There are two broad tests that can be conducted to find out if one has flat feet. They are by visual tests or by imaging tests.
These tests are performed by visual observations and do not require any equipment. Some of them are
i. Shoe inspection which will be used to determine if the feet are faulty and tend to lean towards the inner parts of the feet. The wear on the heel area of the shoe will determine if the person has flat feet.
ii. Wet footprint exam is done to find out if the arch is high or fallen. The procedure involves the wetting of the feet and standing on a flat surface. If the footprints between the balls of the feet and the heels are showing completely, the feet are considered flat.
iii. Tiptoe tests are done to determine if a flat foot is rigid or flexible. A flexible flat foot shows an arch when on tiptoe while a rigid flat foot does not show a distinct arch.
This is carried out if the cause of the flat feet needs to be discovered or if the flat feet cause pain, discomfort, and disability to a person. The imaging tests often carried out are:
These are tests carried out by using electromagnetic waves and film to capture the images of bones, tissues, and organs.
The electromagnetic rays also known as x-rays are passed through the body onto a film and a white negative image of inner solid structures of the body is shown.
The thicker a body part is, the smaller the amount of x-ray that passes through it and the whiter it appears on the film.
X-rays are avoided during pregnancy since the dose of the electromagnetic waves might be too high for a fetus and can cause defects.
Computed Tomography (CT)
This is also known as a CAT scan and is used to capture a more detailed image of the body than the conventional x-ray scan.
It is a short and painless procedure in which a computer and x-rays create cross-sectional and 2-dimensional images of the bones, organs, and tissues.
The CAT scanner is shaped like a doughnut and it goes around the body part to be scanned. A series of images from various angles are captured. The images are shown as slices of the body structures in a computer and are merged to show a complete image of the part of the body.
This is also known as sonography and is the use of sound waves of high frequency to produce images of inner body parts.
A gel is placed on the area to be scanned and the transducer is used to apply the sound waves and collect the waves that bounced back. These waves are interpreted by a computer into 3-dimensional movements and images of the internal body system.
Magnetic Resonance Imaging (MRI)
The MRI scan creates cross-sectional images of the organs, bones and blood vessels using radio waves, a powerful magnet and a computer.
The MRI scanner looks like a wide tube that a person can slide in, lying on a flat surface. Unlike the X-ray and the CAT scan, the MRI does not use radiation.
Treatment of Flat Feet
What Are Insoles?
There are different ways to tackle flat feet depending on the causes and severity of symptoms.
Different treatment methods available are the use of orthotic insoles. and shoe modifications, rest, ice to reduce swelling, non-steroidal pain relief drugs, exercises, and corticosteroids injections.
Insoles or footbeds are materials placed inside shoes for a better fit, warmth, and comfort. They don’t make shoes smaller but helps to fill up all the spaces between your foot and the shoe.
They can be used to correct foot disorders like flat feet, bunions, claw toes, heel spurs, and plantar fasciitis. They also keep the shoes fresh because they are removable and washable.
Types of Insoles
Shoe insoles or orthotic insoles. are both inserts used in shoes for different purposes, but they are slightly different.
While inserts and insoles are available for purchase anytime, orthotics must be prescribed by a podiatric and are manufactured using a customized mold.
Shoe inserts are made to tackle problems for a specific area of the foot and not to affect other parts.
Inserts like heel lifts are made to lift to heel and reduce ankle pain, metatarsal pads are placed behind the ball of the foot for pain relief and heel cups tackle heel pain by absorbing shock on the heel.
Shoe insoles, on the other hand, covers the length of the shoe. They can be flexible or rigid and used to support the foot or the arch.
Orthotics are made on-demand for each foot and are prescribed by a specialist depending on the purpose of use. They are made from a 3-dimensional mold of the user’s foot which can be obtained from an optical scanner, plastic mold or a flexible foam mold.
There are three main groups of orthotics:
They are custom-made biomechanical insoles designed to realign the ankles and feet into an efficient position.
Just as glasses correct poor vision, custom orthotics correct specific foot disorders by reducing stress and redirecting gait patterns.
They fit into a shoe but unlike an insole, they are made with an exact imprint of the user’s foot.
The longer and more frequent a custom orthotic are worn, the better. The insoles that are bought with shoes should be removed and replaced with the custom orthotic for better results.
They are made from soft and flexible materials to cushion and relieve pain and pressure from a painful part of the foot. Some correct foot abnormalities and treat painful callouses, foot ulcerations due to diabetes, and sore bones.
They can be made with materials like leather, plastic foams, rubber, and cork materials.
They are made with either plastic (flexible or rigid) and graphite materials and can be used to correct abnormalities and accommodate pains on the foot.
They are thinner than other types of orthotics and fit easily into shoes.
They are mostly used to manage or treat and ankle pain, heel pain, arch pain, big toe pain, toe joint pain, ankle tendonitis, bursitis, and shin splints.
Best Insoles for Flat Feet
FonsBleaudy Orthotic Insoles with Arch Support
These insoles are highly recommended by podiatrists and made with high-grade materials and premium design. They are used in the treatment of knee pain, shin splints, and Achilles tendonitis.
The fabric used in its manufacture is anti-slip and provides cushioning and support foot alignment. It is also designed to help to prevent sports injuries, relieve pain, ease stress and provide support for fallen arches.
The insoles help to distribute weight evenly and protect the heel from the impact of walking, hiking and running.
PCSsole ¾ Orthotics Shoe Insoles
These ¾ orthotic insoles are designed to provide arch support and comfort for people with plantar fasciitis, flat feet, and heel pain. They help to stabilize the feet and adjust them to proper alignments.
The 35mm high arch support is used to correct fallen arches. The stiff EVA materials used in the production of the insoles help to provide support to the foot and reduce pressure from the heel.
The materials are breathable and do not require any cutting or size adjustment. It can fit into any type of working or casual shoes.
Samurai Insoles Instant Relief Orthotics for Flat Feet
They are designed by a podiatrist and a team of experts to address the root cause of pain and fatigue of flat feet.
They are used to gently correct the effects of fallen arches and provide soft support of the feet. They are built to offer quick relief from heel pain and plantar fasciitis for people who cannot tolerate rigid insoles.
They are slim, lightweight and are available in various shoe sizes. They provide ample support, bounce and cushion to the arch and are suitable for running, jumping, jogging, skiing, cycling and walking.
SmartSole Exercise Insoles for Plantar Fasciitis, Flat Feet, and Shin Splints Relief
This is specially designed for flat feet, shin splints and plantar fasciitis. The deep heel cup that has a gel insert absorbs shock extensively and correct fallen arches and stabilize the foot.
The Anti-Fatigue and shock-absorbing cushioning relieve pressure from joints, back and knees thereby reducing fatigue and pain.
The materials used as the top fabric are anti-microbial which keeps the feet healthy while the base which is made of nylon adds great support to the feet.
They can fit into any type of shoes and do not require any trimming or cutting.
Footminders Comfort Orthotic Arch Support Insoles for Sports Shoes and Work Boots
This insole has a firm arch support design that helps to reduce foot pain caused by flat feet and plantar fasciitis. It is highly recommended by chiropractors and podiatrists.
It can be used with work boots and all sports shoes. It is also ideal for people that walk or stand for a long time.
They are specially designed to provide cushioning from impacts of walking, running, standing and hiking on the feet. It also helps with the biomechanical re-alignment of the hips, knees, ankles, and feet.
WalkHero Comfort and Support Insoles
This insole is designed to be used on wide and thick shoes like basketball shoes, work boots, running shoes, and the likes.
It is produced with premium materials that cool down the feet and offer excellent shock absorption. Its arch support design helps to improve foot alignment, ease pain and stress caused by flat feet and other foot disorders and provide comfort.
It has a deep heel cup that protects the heels from impacts from walking and running and can be used every day.
EasyFeet Plantar Fasciitis Arch Support Insoles for Men and Women
These are premium shoe insoles recommended by podiatrists which helps to minimize pain and offer comfort. It is used to relieve pain from flat feet, plantar fasciitis, back pain, knee pain, ankle pain, heel spurs, shin splints, bunions, and metatarsalgia.
They can be used in basketball, casual, sports, hiking, tennis, snowball, golf, ski, work, and orthopedic shoes.
It is designed with the Anti-pronation Biomechanical Reinforcement Technology that offers a great level of arch support, comfort, and stability.
The arch support made with hard thermoplastic polyurethane and a foam base of premium quality. The breathable top material reduces friction and heat and provides comfort. These insoles can be trimmed to fit different sizes.
Physix Gear Sport Full Length Orthotic Inserts with Arch Support
These are designed to balance the foot structure and provide convenient and soothing relief to those with shin splints, flat feet, Achilles tendonitis, and runner’s knee. It helps to relieve heel pain, metatarsal pain, and correct abnormal gait.
The materials used are of high quality, durable and are medical grade. The EVA foam and polyurethane material provide a cushion effect that feels like walking on clouds.
The deep heel cup provides stability while the ultra-thin top fabric pampers the feet during physical activities. They can be used for rock climbing, sports, ball games, camping, running, and d jogging.
They are also perfect for those that stand on their feet for a long time (factory workers and retail employees) and they provide long hours of cushioning and comfort.
The ergonomic non-slip design provides support for correct foot posture and is carefully produced to reduce pain and discomfort. It is also designed with more room at the toe box so that it can fit into any type of shoe.
The non-slip heel stays in place all day and provides exception shock absorption.
PCSsole Orthotic Arch Support Shoe Insoles for Flat Feet
This is a medical-grade insole that can be used to manage foot pain, heel pain, arch pain, flat feet, ankle pain, and plantar fasciitis.
It helps the foot to properly distribute pressure and absorb shock evenly. The deep heel cradle design helps to keep the foot bone in a vertical position and increase stability.
The latex pad is built to aid in more shock absorption while the EVA foam base provides comfort during physical activities like walking and running.
The fabrics used also have cooling effects on the feet and absorb sweat from the feet. The insoles can be cut down to size and can be moved from one shoe to another.
How Are Orthotic Insoles Made?
The processes involved in the production of orthotics are intricate and detailed. It involves multiple steps and strict adherence to the prescriptions of the podiatrist.
There are three main steps taken in the production of orthotic insoles. These steps are casting, manufacturing and cushioning.
Step I: Casting
In this stage, the legs are thoroughly examined, and measurements are also taken. The foot cast is taken in a neutral position, either lying or sitting down to avoid the wrong impressions due to body weight.
The cast of the feet is taken with the use of a wet plaster wrapped around the foot and allowed to solidify.
The semi-hard hollow mold (positive mold) is filled with another mold (negative mold), allowed to sit for 24 hours and the flexible mold removed. The solid mold which has the same dimensions as the legs of the user is taken to the laboratory.
Step II: Manufacturing
The negative mold is taken to the laboratory and together with the materials, measurements and other accessories to be used in the production of the orthotic.
The cast is pressed on the material to be used to produce the orthotic under very high temperatures.
There are different materials that are used in making orthotics. They are to be comfortable, durable, flexible and strong enough to bear the forces that the bodyweight put on the feet. Some of these materials are plastics (polypropylene) and graphite.
They are materials made up of elements like carbon, hydrogen, nitrogen, oxygen, Sulphur, and chlorine. They have high molecular weight and are called polymers.
The production of plastics is based on the carbon atom and it joins with oxygen, Sulphur, hydrogen or nitrogen to form long chains of a polymer called thermoplastics. 97% of plastics are thermoplastics.
Thermoplastics can melt and they are made up of identical repeated small units called monomers. Some monomers can be short while some are very long. When these monomers are joined in a process called polymerization, they become polymers.
The bonds that join the carbon atoms to other elements in thermoplastics are single bonds. When the bonds that join the carbon atoms and the other elements are double or triple bonds, the end-product is called thermosets.
Thermosets cannot melt and are used in making adhesives, polyester, bathtubs and boat hulls.
Polymerization is of two types:
Addition or Chain-Growth Polymerization
This occurs when monomers form a branch or linear structure to form a polymer without the loss of an atom or molecule. The four types of addition polymerization are free radical polymerization, anionic vinyl polymerization, cationic polymerization, and coordination polymerization.
This type of polymerization is used to produce plastics like polystyrene, polyethylene, and polyvinyl chloride.
Condensation or Step-Growth Polymerization
This is a process by which small molecules react with one another to form larger units and produce a by-product like water, methanol or HCl gas. The by-products are removed before this process can produce the intended products.
Sometimes, these by-products are useful as raw materials for other manufacturing processes and can be reused.
Nylons and polyesters are made through this type of condensation polymerization.
When the monomers involved in the polymerization process are the same, the polymer produced is called a homopolymer. When the monomers are not identical, the end-product is called a copolymer.
This is one of the forms of natural carbon found in igneous and metamorphic rocks. It is very soft, has very low gravity, inert (doesn’t react with other elements), has a very lightweight and heat resistant.
These properties make it a very useful material for the manufacture of many products.
There are two forms of graphite, natural and synthetic graphite.
This is formed when the carbon in the earth crust is subjected to temperatures as high as 750oC and pressures as high as 75000lb/sq. in.
There are three forms of graphite namely flake (formed from regional metamorphism), amorphous (formed from coal stem metamorphism), and lump graphite (formed from hydrothermal metamorphism).
This is produced when a hydrocarbon is converted to coke by heating in the absence of oxygen, then calcinated and heated to about 3000oC.
There are two forms of synthetic graphite: graphite blocks and electrodes. Graphite blocks also known as isotropic graphite are used for energy storage while electrodes are used in furnaces for melting iron.
Step III: Cushioning
Materials that cushion the hard plastics and graphite are used in cushioning the orthotic to provide more comfort.
The materials commonly used to cushion the plastic and graphite core of the orthotic insoles are polychloroprene, ethyl-vinyl acetates, and silicones.
How to Make A Good Choice of An Insole
The type of insole to be used is determined by a lot of factors. Although insoles are produced to provide support and comfort, it is very important to buy the right insoles.
Some of the factors to consider while choosing an insole are arch type, gait, and purpose of purchase.
There are three types of feet arches which are
A normal arch is also known as the neutral or moderate arch. The body weight is distributed evenly by this type of arch and is efficient biomechanically.
Stress and poorly fitted footwear can make this type of foot susceptible to foot disorders like posterior tibial tendon dysfunction, metatarsalgia, and heel pain.
Insoles for this foot type should provide enough cushioning and comfort to prevent foot pain.
High arch also is known as supinated or Cavus foot is very rigid and the force exerted on the foot by body movements is absorbed by the heels and forefoot. This causes pains in the weight-bearing parts especially after physical activity like running.
This type of foot is likely to develop foot disorders like arch strain, foot calluses, plantar fasciitis, metatarsalgia, claw toes, and heel pain.
The orthotic insole for this foot type should have a thick metatarsal cushion and superb arch support to help in shock dispersion.
Flat arch is also known as the flat or overpronated foot which can be flexible or rigid. The force exerted on the foot by the body is directed back to the knee and hips.
This type of foot is likely to develop foot problems like bunions, knee pain, tendonitis, plantar fasciitis and, heel spurs.
The orthotic insole for this foot type should provide arch cushioning and thickness that can help with foot alignment.
This is simply defined as the way a person balances and coordinates the muscles while walking. Gaits can be normal or abnormal. Abnormal gaits can be caused by factors like inner ear dysfunction, stroke, arthritis, nervous system disorder, and tight shoes.
Types of abnormal gait are
Parkinsonian gait also is known as propulsive gait is characterized by a head that is bent forward and a stooped posture.
Spastic gait also is known as ataxic gait is characterized by a dragged foot and stiff muscles. This is normally caused by nerve-damaging diseases like polio.
Hemiplegic gait is characterized by a leg that is more extended than the other. During movements, the affected leg cannot be lifted but swung. It is caused sometimes by stroke
Waddling gait also known as myopathic gait is characterized by bent hips that are shifted to maintain proper balance. Pregnancy and muscular dystrophy can lead to this type of abnormal gait.
Scissors gait also is known as diplegic gait which is characterized by legs that are swung at the waist and knees that are slightly bent. The knees and thighs cross and hit each other during movements like scissors. This is found in people with cerebral palsy.
Steppage gait or neuropathic gait is characterized by a hanging foot and toes that drag while walking.