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Biomechanics and its related study deal with the forces that act against the body and affect things like our movement. In podiatry, biomechanics are studied to determine the movement of the ankle, toes, and the foot, as well as the forces that impact them. Podiatrists who train in this specialty are able to effectively diagnose and treat conditions that affect people’s everyday movement.
Regardless of your lifestyle, age, or any other factors, many people experience foot problems throughout their lives. Twists and turns, improper balance, and added weight are just a few of the things that can add stress to the feet. These issues can also limit our bodies’ mobility that we often take for granted. Pain in the feet and ankles can also trickle up towards the lower legs, knees, hip, and even back area. This affects the way you move around on a daily basis.
Biomechanics and its related study deal with forces that act against the body and affect things like our movement. In podiatry, biomechanics are studied to determine the movement of the ankle, toes, and the foot, as well as the forces that impact them. Podiatrists who train in this specialty are able to effectively diagnose and treat conditions that affect people’s everyday movement.
Regardless of your lifestyle, age, or any other factors, many people experience foot problems throughout their lives. Twists and turns, improper balance, and added weight are just a few of the things that can add stress to the feet. These issues can also limit our bodies’ mobility that we often take for granted. Pain in the feet and ankles can also trickle up towards the lower legs, knees, hip, and even back area. This affects the way you move around on a daily basis.
The history of studying biomechanics dates back to ancient Egypt at around 3000 B.C., where evidence of professional foot care has been recorded. Throughout the centuries, advances in technology, science, and an understanding of the human body led to more accurate diagnosis of conditions such as corns for example. In 1974, biomechanics garnered a large audience when Merton Root founded Root Lab to make custom orthotics. He proposed that corrections of certain conditions could be implemented to gain strength and coordination in the area. Due to his research, we still use his basic principle of foot orthotics to this day.
As technology has improved, so have the therapeutic processes that allow us to correct deficiencies in our natural biomechanics. Computers can now provide accurate readings of the forces, movements, and patterns of the foot and lower leg. Critical treatment options can be provided to patients now who suffer from problems that cause their biomechanics to not function naturally. The best results are now possible thanks to 3D modeling and computing technologies that can take readings and also map out what treatment will do to the affected areas.
These advanced corrective methods were able to come to light thanks to an increase in both the technologies surrounding biomechanics and also the knowledge of how they work naturally. For example, shoe orthotics are able to treat walking inabilities by realigning the posture deviations in patients caused by hip or back problems. Understanding foot biomechanics can help improve movement and eliminate pain, stopping further stress to the foot. Speak with your podiatrist if you have any of these problems.
Have you ever gotten up from a chair or out of bed in the morning, and upon taking that first step, feel like your heel has stepped on a tack? Many people experience a feeling of sharp pain which radiates into their arch from their heel and which does not allow them to put their heel on the floor. Sometimes they need to sit back down, stand only on their toes and use the wall for balance. If you can take a few steps, it seems to go away and lessen, allowing you to then resume your activity. Later, throughout your day and after a period of rest, it can happen again. If this sounds familiar you may be suffering from your first attack of heel pain.
Heel pain is a debilitating condition that affects day to day activities. Running and walking both causes stress on the heel because the heel is the part of the foot that hits the ground first. This means that the heel is taking on your entire weight. Diagnosis and treatments for heel pain can be easily found through your podiatrist.
Plantar Fasciitis
One of the main causes of heel pain is a condition known as plantar fasciitis. The plantar fascia is a band of tissue that extends along the bottom of the foot, from the toe to the bottom of the heel. A rip or tear in this ligament can cause inflammation of these tissues, resulting in heel pain. People who do not wear proper fitting shoes are often at risk of developing problems such as plantar fasciitis. Unnecessary stress from ill-fitting shoes, weight change, excessive running, and wearing non-supportive shoes on hard surfaces are all causes of plantar fasciitis.
Achilles Tendonitis
Achilles tendonitis is another cause of heel pain. Similar to plantar fasciitis, inflammation of the Achilles tendon will cause heel pain due to stress fractures and muscle tearing. A lack of flexibility of the ankle and heel is an indicator of Achilles tendonitis. If left untreated, this condition can lead to plantar fasciitis and cause even more pain on your heel.
Heel Spur
A third cause of heel pain is a heel spur. A heel spur occurs when the tissues of the plantar fascia undergo a great deal of stress, leading to a separation of the ligament from the heel bone entirely. This results in a pointed fragment of bone on the ball of the foot, known as a heel spur.
Bunions are large bony bumps at the base of the big toe. Medically known as hallux valgus, a bunion is a misalignment of the metatarsophalangeal joint, or big toe joint. The misalignment will generally worsen with time if left untreated.
The exact cause of bunions is unknown, with genetics seen as a potential cause. High heels and poorly-fitted footwear, rheumatoid arthritis, and heredity all seem to be potential factors behind the exacerbation of bunions. Women have been found to be more likely to develop bunions in comparison to men.
Bunions do not always produce symptoms. The best way to tell is if the big toe is pushing up against the next toe and there is a large protrusion at the base of the big toe. You may or may not feel pain. Redness, swelling, and restricted movement of the big toe may be present as well.
Podiatrists use a variety of methods to diagnose bunions. If there are symptoms present, podiatrists will first consider that it is a bunion. If not, a physical examination will be conducted to check function of the big toe. Finally, an X-ray may be taken to view the extent of the bunion and confirm it is a bunion.
Typically, nonsurgical methods are used to treat bunions, unless the bunion has become too misaligned. Orthotics, icing and resting the foot, roomier and better fitted shoes, taping the foot, and pain medication are usually utilized first. If the bunion doesn’t go away or causes extreme pain, surgery may be required. Surgeons will either remove part of the swollen tissue or bone to straighten the toe out.
If you have a bunion, it is recommended to see a podiatrist. The longer it is left untreated, the worse it may get. Podiatrists can properly diagnose and treat a bunion before it gets worse.
Cracked heels can make life very frustrating and embarrassing when displaying the bare feet. Aside from being unpleasing to the eye, they can also tear stockings and socks and wear out shoes at a faster rate. When severe, cracked heels may cause pain or infection.
Cracked heels are a problem for those who are athletic, those who may walk a lot, and those who have especially dry skin. Those who use medication that dry the skin, those who swim often, wearing certain types of shoes, and those who are diabetic may have trouble with cracked heels. Seniors whose skin produces less oil may also have trouble with cracked feet. There is no one way to develop cracked feet, and there is no cure.
Today, the market consists of numerous products that have a variety of ingredients to promote healing. Some of these are over-the-counter. Others are prescribed by a doctor, especially for those who have chronic dry feet and heels.
Some doctors recommend wearing socks at night for those with rough skin. This helps further healing, and helps creams stay on longer and better absorb into the skin.
One way to alleviate dryness that causes cracked heels is by using moisturizers both day and night. Another way is to make sure the skin is clean and dry at all times. Using a pumice stone to buff away dead skin before putting on moisturizer can also help. Cracked heels will not respond to the cream unless the outer layer of skin is first removed through exfoliation. After exfoliation, lotion or ointment will be absorbed by the skin more easily.
Foods that produce healing and balance can also help the skin from within. Everything that is put into the body can either help it or hurt it. Taking supplements of omega-3 fatty acids and zinc can also be very beneficial.
Nevertheless, not all products are guaranteed to help treat cracked feet. Seeing a professional is best if other treatments options were unsuccessful. A podiatrist should be able to give the best advice to help with this problem.
Flatfoot is a foot disorder that is not as straightforward as many people believe. Various types of flatfoot exist, each with their own varying deformities and symptoms. The partial or total collapse of the arch, however, is a characteristic common to all types of flatfoot. Other signs of flatfoot include:
- “Toe drift,” or the pointing outward of the toes and the front part of the foot
- The tilting outward of the heel and the tilting inward of the ankle
- The lifting of the heel off the ground earlier when walking due to a tight Achilles tendon
- Hammertoes
- Bunions
One of the most common types of flatfoot is flexible flatfoot. This variation usually starts in childhood and progresses as one ages into adulthood. Flexible flatfoot presents as a foot that is flat when standing, or weight-bearing. When not standing, the arch returns. Symptoms of flexible flatfoot include:
- Pain located in the heel, arch, ankle, or along the outside of the foot
- Overpronation, or an ankle that rolls in
- Shin splint, or pain along the shin bone
- General foot aches or fatigue
- Pain located in the lower back, hip, or knee
Your podiatrist will most likely diagnose flatfoot by examining your feet when you stand and sit. X-rays may be taken to define the severity and help determine the treatment option best for your condition. Nonsurgical treatments can include activity modification, weight loss, orthotics, immobilization, medications, physical therapy, shoe modifications, and ankle foot orthoses (AFO) devices. If nonsurgical methods prove ineffective, surgery may be considered. Multiple surgical procedures can correct flatfoot; and depending on your specific condition, one may be selected alone or combined with other techniques to ensure optimal results.
A new treatment for fungal nails, or onychomycosis, which has grown in popularity in recent years, is laser treatment. Laser treatment involves the use of a laser that kills fungus in the toenail with heat. Laser therapy causes no side effects and does not affect nearby healthy tissue.
Toenail fungus afflicts almost 10 percent of the U.S. population and is more common among the elderly. The most common symptom of toenail fungus is the discoloration and thickening of the nail. The nail can also become brittle and a foul smell may be produced. In rare cases, pain might be present. While it is not a serious condition, it can lead to a perception of disgust amongst those it affects. There are several different fungi that cause fungal infections. These include dermatophyte, yeast, and mold. The most common of these is dermatophyte.
Diagnosis for fungal nails involves a podiatrist utilizing microscopy and fungal cultures. This will allow the doctor to determine whether it is a fungus or another condition, such as lichen planus, psoriasis, nail damage, and onychogryphosis.
Fungus in the nails can be hard to get rid of with over-the-counter drugs. This is due to the nail being hard and protective, with fungus able to slip between the nail bed and plate. Furthermore the slow growth of the nail increases the difficulty of fungus going away. Laser treatment seeks to get around this by directly penetrating through the nail and killing the fungus. The laser is used on each infected nail for a couple of minutes. Patients then typically return several weeks or months later for another laser treatment. During this time the podiatrist will routinely observe the foot and infection. It is also recommended to wear clean socks and shoes and allow the feet to dry and breathe to prevent toenail fungus.
Laser treatment is still a relatively new treatment and not all podiatrists have laser machines. Ask your podiatrist if they do laser treatment for toenail fungus and if it is right for you.
An ankle sprain occurs when one or more ankle ligament gets overly stretched. Ligaments are strong bands of tissue that bind and support the bones and other structures that make up the ankle. In more severe ankle sprains, the ligament(s) tear—either partially or completely—and there may be an audible popping noise at the moment of injury.
Ankle sprains are quite common and can occur when the ankle rolls outwardly (eversion) or inwardly (inversion), causing the ligament(s) to stretch beyond normal limits, or even tear. Falls, twists, or blows to the ankle during sports or other activities can cause this injury, as well as wearing improper footwear, running on uneven surfaces, or having weak ankles.
Depending on the injury’s severity, an ankle sprain will be classified as Grade I, Grade II, or Grade III. Grade I sprains involve ligament(s) being overly stretched but not torn, with symptoms of mild pain, swelling, and ankle instability. There may also be some difficulty bearing weight. A Grade II sprain usually involves a partial tear of the ligament which brings more intensity in these symptoms, along with possible bruising. With a Grade III sprain, the ligament is completely torn, the symptoms are severe, and it may not be possible to put weight on the affected foot at all.
To diagnose and grade an ankle sprain, a podiatrist will perform a physical examination, checking for tenderness and range of motion in the ankle. For more severe sprains, X-rays or other imaging studies may be necessary.
It is vitally important to have an ankle sprain treated properly as improper healing often leads to future ankle sprains and possibly even chronic ankle stability. Treatment for an ankle sprain will vary, depending on its severity, and may include the RICE method (Rest/Ice/Compression/Elevation), physical therapy, bracing, medications, and possibly even surgery to repair a torn ligament. Rehabilitation is very important for the sprain to heal properly and to restore functionality.
The natural weight that pregnant women gain causes their center of gravity to be completely altered. This causes them to have a new weight-bearing stance which adds pressure to the knees and feet. As a result, pregnant women often experience severe foot pain. The two most common foot issues experienced by women in their pregnancies are edema and over-pronation. It is important for all pregnant women to learn more about how to take care of their feet so they are more comfortable during their pregnancy.
Over-pronation, which is commonly referred to as flat feet, is caused when a person’s arch flattens out upon weight bearing. This causes the person’s feet to roll inward while walking. Pregnant women often experience this due to the sudden weight they gain.
Edema, also referred as swelling in the feet, typically occurs in the later part of the pregnancy. It is the result of the extra blood accumulated in the pregnant woman’s body. The enlarged uterus puts more pressure on the blood vessels in the pelvis which causes leg circulation to slow down. This causes blood to pool in the lower extremities.
Fortunately, there are ways to treat both edema and over-pronation. Edema can be treated by elevating the foot as often as possible. Wearing proper fitting footwear will also be helpful for those with edema. A treatment method for over-pronation could be orthotics. Orthotic inserts should be designed with appropriate arch support and medial rear foot for your foot.
It is best for pregnant women to buy new shoes during the day, because this is the time where swelling is at its peak. Pregnant women also shouldn’t rush when buying shoes. It is always advised that you make sure your shoes fit properly but this is especially important during pregnancy.
If you are a pregnant woman, you should consult with a podiatrist in order to make sure your feet are healthy throughout the entirety of your pregnancy.
There are several systemic diseases, or diseases that affect the whole body, that either display symptoms in the feet or affect the health of the feet. Common systemic diseases that affect the overall health of the feet, and the patient’s ability to walk comfortably, include gout, diabetes mellitus, neurological disorders, and arthritis, among others.
In gout, which is caused by an excessive buildup of uric acid in the body, the most common symptoms of pain, inflammation, and redness occur at the metatarsal/phalangeal joint at the base of the big toe. Any excess levels of uric acid crystallize and are deposited in tendons, joints, and surrounding bone and muscle tissue. Gout is commonly treated with NSAIDs to relieve pain and inflammation and other drugs to lower uric acid levels in the body. Gout most commonly affects those who are overweight, have low protein diets and lead a more sedentary lifestyle.
Diabetes mellitus is an increase in the level of blood sugar in which the body cannot counteract with naturally occurring insulin in the body. The three types of diabetes, Type I, Type II and Gestational Diabetes, are all signs the body is either not producing enough insulin or is not efficiently using the insulin that is produced. Gestational diabetes only affects women who are pregnant and have never, prior to pregnancy, exhibited symptoms of the disease.
There are two main issues that affect the feet that are commonly caused by diabetes. They include diabetic neuropathy and peripheral vascular disease. Diabetic neuropathy can lead to damaged nerves and affect the feet through numbness and loss of sensation. Peripheral vascular disease restricts the flow of blood to the foot and can, in extreme cases, lead to the necessity of amputating the foot. Peripheral issues that are caused by diabetes and can affect the foot include athlete’s foot, nail infections, corns, blisters, bunions, severe dry skin, plantar warts and ingrown toenails. These can all be attributed to the decrease of blood flow to the foot.
Neurological disorders and rheumatoid arthritis can also have severe impact on the health of the feet. Neurological disorders can affect the nerves in the main structure of the foot and cause loss of sensation and possible decreased muscle response. Rheumatoid arthritis can affect the bones and joint structures of the foot, making it impossible to walk normally without serious pain.
All systemic diseases that affect the foot can effectively be treated to minimize joint and muscle damage if they are diagnosed early and treated with medication and lifestyle therapy. Diabetes patients must monitor their blood sugar levels and work with their physician to keep their levels as close to normal as possible. Rheumatoid arthritis patients should work with their physician to ensure the proper medications are being taken to reduce the amount of damage to the joints of the body.
Running may seem like a simple to do. However, running is actually a complex movement that puts stress on the ligaments, bones, and joints of the body. Selecting the correct running shoe is important for increasing performance and avoiding risk of injury. Running shoes should be selected based on your foot type. Considerations such as trail versus road shoes are important. Your foot type dictates the degree of cushioning, stability and motion control you require. The most accurate way to learn your foot type is to visit a local shop that specializes in running shoes. Professionals can measure your arch type, stride and gait and help you with your shoe needs.
The design of running shoes is created around the idea of pronation. Pronation is the natural rolling movement of your ankle from the outside to inside when your foot strikes the ground. If you run properly you strike the ground on the outside of your heel and roll in the direction of your big toe before pushing off once more. Pronation is beneficial because it assists the lower half of your body in absorbing shock and storing energy. Those considered neutral runners pronate correctly and do not need running shoes that help correct their form. Neutral runners can choose from a wide variety of shoes, including barefoot or minimal types. However, those who have arch problems or who adopt an incorrect form while running may experience too much or too little pronation. They may require running shoes that offer additional support.
Those who overpronate experience an over-abundance of ankle rolling. Even while standing, those who severely overpronate display ankles that are angled inward. It is not uncommon for them to have flat feet or curved legs. The tendency to overpronate may cause many injuries. Areas that tend to become injured are the knees, ankles, and Achilles tendon. If you find that you have a tendency to overpronate, you should look at shoes that provide extra stability and motion-control. Motion-control shoes are straight and firm. Shoes of this type do not curve at the tip. The restricted flexibility along the middle of the shoe prohibits the foot from rolling too far inward as your foot strikes the ground.
A less common problem is underpronation. Underpronation, also called supination, is when the feet are unable to roll inward during landing. Those who underpronate have feet that lack flexibility and high arches. This prevents any kind of shock absorption, even though it does place less rotational stress on ankles and knees. This added force can cause fractures, ligament tears, and muscle strains because the legs are trying to compensate for the impact. Those who underpronate need shoes with more cushioning and flexibility. If you have a tendency to underpronate, selecting stability or motion-control shoes may cause you more problems by continuing to prevent pronation.
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A neuroma is a thickening of nerve tissue and can develop throughout the body. In the foot, the most common neuroma is a Morton’s neuroma; this typically forms between the third and fourth toes. The thickening of the nerve is typically caused by compression and irritation of the nerve; this thickening can in turn cause enlargement and, in some cases, nerve damage.
Neuromas can be caused by anything that causes compression or irritation of the nerve. A common cause is wearing shoes with tapered toe boxes or high heels that force the toes into the toe boxes. Physical activities that involve repeated pressure to the foot, such as running or basketball, can also create neuromas. Those with foot deformities, such as bunions, hammertoes, or flatfeet, are more likely to develop the condition.
Symptoms of Morton’s neuroma include tingling, burning, numbness, pain, and the feeling that either something is inside the ball of the foot or that something in one’s shoe or sock is bunched up. Symptoms typically begin gradually and can even go away temporarily by removing one’s shoes or massaging the foot. An increase in the intensity of symptoms correlates with the increasing growth of the neuroma.
Treatment for Morton’s neuroma can vary between patients and the severity of the condition. For mild to moderate cases, padding, icing, orthotics, activity modifications, shoe modifications, medications, and injection therapy may be suggested or prescribed. Patients who have not responded successfully to less invasive treatments may require surgery to properly treat their condition. The severity of your condition will determine the procedure performed and the length of recovery afterwards.
Plantar warts are growths that typically appear on the heels or other weight-bearing areas of the feet. These warts are caused by the human papillomavirus (HPV). The virus enters the body through breaks in the skin, such as cuts, that are on the bottom of the feet. Plantar warts are more likely to affect children and teenagers, people with weakened immune systems, people who have a history with plantar warts, and people who walk barefoot in environments exposed to a wart-causing virus.
If you suspect you have plantar warts, you may have the following symptoms: pain or tenderness while walking, a lesion that interrupts the ridges in the skin of your foot, small fleshy lesions on the bottom of the foot, or a callus where a wart has grown inward over a well-defined spot on the skin.
HPV causes plantar warts to form and is very common. There are more than 100 kinds of the virus in existence. However, only a few of them cause warts on the feet. The other types of HPV are likely to cause warts on other parts of the body.
If you have plantar warts, your podiatrist may try different treatment methods depending on your specific case. Some treatments for plantar warts are peeling medicines (salicylic acid), freezing medicines (cryotherapy), or surgical procedures. Laser treatments and vaccines are also used to treat plantar warts.
Diabetes is the condition in which the body does not properly process food for use as energy. People with Type 1 diabetes cannot produce insulin, which is required for glucose to feed your body’s cells. It is typically caused by the immune system mistaking healthy cells for foreign invaders and destroying the insulin-producing cells in the pancreas. On the other hand, people with Type 2 diabetes cannot respond to insulin properly, and eventually cannot produce enough. The Centers for Disease Control and Prevention reports that over 30 million people in the United States have diabetes, with 1 in 4 having no idea they have it. Surprisingly, diabetes is the seventh leading cause of death in the US. The symptoms of diabetes include frequent urination, fatigue, hunger, and even blurry vision.
Diabetes can also affect the feet as well. Over time, diabetes can cause nerve damage to your feet, which could then lead to symptoms such as tingling, pain and numbness in the feet. Neuropathy can be very dangerous to a person with diabetes, since it prevents them from feeling injuries such as cuts or blisters in the feet, and if not detected early enough, may lead to infection. Neuropathy can also lead changes in the shape of your feet and toes. The best way for people with diabetes to prevent or delay neuropathy is keeping their blood glucose levels in their target range. This consists of eating right, having the correct amount of exercise, and taking medications.
Diabetes can also create calluses and foot ulcers as well. Calluses build up faster and occur more frequently with those affected by diabetes. If there are too many calluses, therapeutic shoes and inserts may be required. It is important to have calluses trimmed by a health professional, as doing it yourself may lead to infections. If these calluses continue to develop and thicken, they can lead to foot ulcers. Foot ulcers are open sores, that appear on the ball of the foot or on the bottom of the big toe. These ulcers can lead to future infections if not treated and may possibly result in losing a limb. It is important to report any ulcers to your podiatrist right away. Your doctor may take x-rays to examine the foot and clean out any dead and infected tissue.
Lastly, diabetes can also lead to poor circulation and peripheral arterial disease (PAD). The poor circulation in the feet and leg area is a result of diabetes narrowing and hardening, eventually slowing down the blood flow in that area. The best way to prevent this is to keep away from smoking and follow your doctor’s advice for maintaining blood pressure and cholesterol. PAD is similar to this complication. PAD is when blood vessels narrow or are blocked by fatty deposits. PAD also increases your risk of heart attacks and strokes and is a common condition to those affected by diabetes. The combination of both PAD and neuropathy may lead to infections and can result in amputation of certain limbs. PAD can be prevented with wearing the proper foot wear and regularly taking care of your feet.
If you want to take care of your feet, you should wash and dry them carefully and perform daily inspections to check for cuts, blisters, or swelling. Any physical activity you partake in should be approved by your health care provider. You should also be sure to wear special shoes if advised to do so by your doctor.
Ankles are joints that connect bones in the feet with bones in the lower leg. They are comprised of bones, ligaments, muscles, tendons, blood vessels, and nerves. The ankle joint allows the foot to move side-to-side, as well as up-and-down.
Ankle pain can be caused by a variety of conditions, but is most commonly due to soft tissue injuries such as ankle sprains and strains.
An ankle sprain occurs when one or more of the strong ligaments that support and stabilize the ankle become overly stretched or even torn if the ankle rolls, turns, or twists awkwardly. Depending on the grade of sprain (mild-moderate-severe), there will be varying degrees of pain, swelling, and restricted range of motion, along with tenderness, bruising, and ankle instability. There may even be an audible popping noise at the moment of injury.
Ankle strains can sometimes produce similar symptoms of pain, swelling, and loss of motion, however, they are due to overly stretched muscles and tendons—not ligaments. Ankle strains may also cause muscle cramps in the feet, calves and shins.
Ankle fractures are another common source of ankle pain and occur one or more of the three bones in the ankle become fractured (broken). These breaks can be stress fractures (due to repetitive stress) or traumatic fractures (due to an acute injury). Depending on where and how severe the fracture is, symptoms can include pain and swelling that can sometimes spread up to the knee, bruising or discoloration, and an inability to bear weight. A visible deformity or exposed bone may occur in severe fractures.
Various forms of arthritis may also cause ankle pain. Rheumatoid arthritis (RA) causes the immune system to attack healthy joints, like the ankle joint, by mistake, causing stiffness and swelling in both ankles. Osteoarthritis occurs when cartilage covering the ends of bones wears down, causing the bones to rub against each other. This results in pain, stiffness, and reduced range of motion in the ankle. Gout is a form of arthritis where excess amounts of uric acid in the bloodstream crystallize and build up on joints, causing severe pain and swelling. Reactive arthritis causes joint pain and swelling in the ankle in response to an infection in another part of the body.
Other forms of ankle pain include bursitis (an inflammation of a cushioning bursa sac between tendons and bone), scleroderma (a thickening of connective tissues), chronic ankle instability (caused by improperly healed ankle sprains), Achilles tendon injuries, flat feet, or an infection in the ankle.