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Foot & Ankle

Foot & Ankle Anatomy

Our feet are constantly under stress. It’s no wonder that 80 percent of us will have some sort of problem with our feet at some time or another. Many things affect the condition of our feet: activity level, occupation, other health conditions, and perhaps most importantly, shoes. Many of the problems that arise in the foot are directly related to shoes, so it is very important to choose shoes that are good for your feet.

The foot is an incredibly complex mechanism. This introduction to the anatomy of the foot will not be exhaustive but rather highlight the structures that relate to conditions and surgical procedures of the foot.

Important Structures

The important structures of the foot can be divided into several categories. These include

  • bones and joints
  • ligaments and tendons
  • muscles
  • nerves
  • blood vessels

Bones and JointsThe skeleton of the foot begins with the talus, or ankle bone, that forms part of the ankle joint. The two bones of the lower leg, the large tibia and the smaller fibula, come together at the ankle joint to form a very stable structure known as a mortise and tenon joint.

The mortise and tenon structure is well known to carpenters and craftsmen who use this joint in the construction of everything from furniture to large buildings. The arrangement is very stable.

The two bones that make up the back part of the foot (sometimes referred to as the hindfoot) are the talus and thecalcaneus, or heelbone. The talus is connected to the calcaneus at the subtalar joint. The ankle joint allows the foot tobend up and down. The subtalar joint allows the foot to rock from side to side.

Just down the foot from the ankle is a set of five bones called tarsal bones that work together as a group. These bones are unique in the way they fit together. There are multiple joints between the tarsal bones. When the foot is twisted in one direction by the muscles of the foot and leg, these bones lock together and form a very rigid structure. When they are twisted in the opposite direction, they become unlocked and allow the foot to conform to whatever surface the foot is contacting.

The tarsal bones are connected to the five long bones of the foot called the metatarsals. The two groups of bones are fairly rigidly connected, without much movement at the joints.

Finally, there are the bones of the toes, the phalanges. The joints between the metatarsals and the first phalanx is called the metatarsophalangeal joint (MTP). These joints form the ball of the foot, and movement in these joints is very important for a normal walking pattern.

Not much motion occurs at the joints between the bones of the toes. The big toe, or hallux, is the most important toe for walking, and the first MTP joint is a common area for problems in the foot.

Ligaments and TendonsLigaments are the soft tissues that attach bones to bones. Ligaments are very similar to tendons. The difference is that tendons attach muscles to bones. Both of these structures are made up of small fibers of a material called collagen. The collagen fibers are bundled together to form a rope-like structure. Ligaments and tendons come in many different sizes, and like rope, are made up of many smaller fibers. The thicker the ligament (or tendon) the stronger the ligament (or tendon) is.

The large Achilles tendon is the most important tendon for walking, running, and jumping. It attaches the calf muscles to the heel bone to allow us to raise up on our toes. The posterior tibial tendon attaches one of the smaller muscles of the calf to the underside of the foot. This tendon helps support the arch and allows us to turn the foot inward. The toes have tendons attached that bend the toes down (on the bottom of the toes) and straighten the toes (on the top of the toes). The anterior tibial tendon allows us to raise the foot. Two tendons run behind the outer bump of the ankle (called the lateral malleolus) and help turn the foot outward.

Many small ligaments hold the bones of the foot together. Most of these ligaments form part of the joint capsulearound each of the joints of the foot. A joint capsule is a watertight sac that forms around all joints. It is made up of the ligaments around the joint and the soft tissues between the ligaments that fill in the gaps and form the sac.

MusclesMost of the motion of the foot is caused by the stronger muscles in the lower leg whose tendons connect in the foot. Contraction of the muscles in the leg is the main way that we move our feet to stand, walk, run, and jump.

There are numerous small muscles in the foot. While these muscles are not nearly as important as the small muscles in the hand, they do affect the way that the toes work. Damage to some of these muscles can cause problems.

Most of the muscles of the foot are arranged in layers on the sole of the foot (the plantar surface). There they connect to and move the toes as well as provide padding underneath the sole of the foot.

NervesThe main nerve to the foot, the tibial nerve, enters the sole of the foot by running behind the inside bump on the ankle, the medial malleolus. This nerve supplies sensation to the toes and sole of the foot and controls the muscles of the sole of the foot. Several other nerves run into the foot on the outside of the foot and down the top of the foot. These nerves primarily provide sensation to different areas on the top and outside edge of the foot.

Blood VesselsThe main blood supply to the foot, the posterior tibial artery, runs right beside the nerve of the same name. Other less important arteries enter the foot from other directions. One of these arteries is the dorsalis pedis that runs down the top of the foot. You can feel your pulse where this artery runs in the middle of the top of the foot.

he ankle joint acts like a hinge. But it’s much more than a simple hinge joint. The ankle is actually made up of several important structures. The unique design of the ankle makes it a very stable joint. This joint has to be stable in order to withstand 1.5 times your body weight when you walk and up to eight times your body weight when you run.

Normal ankle function is needed to walk with a smooth and nearly effortless gait. The muscles, tendons, and ligaments that support the ankle joint work together to propel the body. Conditions that disturb the normal way the ankle works can make it difficult to do your activities without pain or problems.

This guide will help you understand

  • what parts make up the ankle
  • how the ankle works

Important Structures

The important structures of the ankle can be divided into several categories. These include

  • bones and joints
  • ligaments and tendons
  • muscles
  • nerves
  • blood vessels

The top of the foot is referred to as the dorsal surface. The sole of the foot is the plantar surface.

Bones and Joints

The ankle joint is formed by the connection of three bones. The ankle bone is called the talus. The top of the talus fits inside a socket that is formed by the lower end of the tibia (shinbone) and the fibula (the small bone of the lower leg). The bottom of the talus sits on the heelbone, called the calcaneus.

The talus works like a hinge inside the socket to allow your foot to move up (dorsiflexion) and down (plantarflexion).

Woodworkers and craftsmen are familiar with the design of the ankle joint. They use a similar construction, called amortise and tenon, to create stable structures. They routinely use it to make strong and sturdy items, such as furniture and buildings.

Inside the joint, the bones are covered with a slick material called articular cartilage. Articular cartilage is the material that allows the bones to move smoothly against one another in the joints of the body.

The cartilage lining is about one-quarter of an inch thick in most joints that carry body weight, such as the ankle, hip, or knee. It is soft enough to allow for shock absorption but tough enough to last a lifetime, as long as it is not injured.

Ligaments and Tendons

Ligaments are the soft tissues that attach bones to bones. Ligaments are very similar to tendons. The difference is that tendons attach muscles to bones. Both of these structures are made up of small fibers of a material called collagen. The collagen fibers are bundled together to form a rope-like structure. Ligaments and tendons come in many different sizes and like rope, are made up of many smaller fibers. Thickness of the ligament or tendon determines its strength.

Ligaments on both sides of the ankle joint help hold the bones together. Three ligaments make up the lateral ligament complex on the side of the ankle farthest from the other ankle. (Lateral means further away from the center of the body.) These include the anterior talofibular ligament (ATFL), the calcaneofibular ligament(CFL), and the posterior talofibular ligament (PTFL). A thick ligament, called the deltoid ligament, supports the medial ankle (the side closest to your other ankle).

Ligaments also support the lower end of the leg where it forms a hinge for the ankle. This series of ligaments supports the ankle syndesmosis, the part of the ankle where the bottom end of the fibula meets the tibia. Three main ligaments support this area. The ligament crossing just above the front of the ankle and connecting the tibia to the fibula is called the anterior inferior tibiofibular ligament (AITFL). The posterior fibular ligaments attach across the back of the tibia and fibula. These ligaments include the posterior inferior tibiofibular ligament (PITFL) and the transverse ligament. The interosseous ligament lies between the tibia and fibula. (Interosseous means between bones.) The interosseus ligament is a long sheet of connective tissue that connects the entire length of the tibia and fibula, from the knee to the ankle.

The ligaments that surround the ankle joint help form part of the joint capsule. A joint capsule is a watertight sac that forms around all joints. It is made up of the ligaments around the joint and the soft tissues between the ligaments that fill in the gaps and form the sac.

The ankle joint is also supported by nearby tendons. The large Achilles tendon is the most important tendon for walking, running, and jumping. It attaches the calf muscles to the calcaneus (heelbone) and allows us to raise up on our toes. The posterior tibial tendon attaches one of the smaller muscles of the calf to the underside of the foot. This tendon helps support the arch and allows us to turn the foot inward. The anterior tibial tendon allows us to raise the foot. Two tendons run behind the outer bump of the ankle (the lateral malleolus). These two tendons, called the peroneals, help turn the foot down and out.

Muscles

Most of the motion of the ankle is caused by the stronger muscles in the lower leg whose tendons pass by the ankle and connect in the foot. Contraction of the muscles in the leg is the main way that we move our ankle when we walk, run, and jump.

The key ankle muscles have been discussed earlier in the section on ligaments and tendons. These muscles and their actions are also listed here.

  • The peroneals (peroneus longus and peroneus brevis) on the outside edge of the ankle and foot bend the ankle down and out.
  • The calf muscles (gastrocnemius and soleus) connect to the calcaneus by the Achilles tendon. When the calf muscles tighten, they bend the ankle down.
  • The posterior tibialis muscle supports the arch and helps turn the foot inward.
  • The anterior tibialis pulls the ankle upward.

Nerves

The nerve supply of the ankle is from nerves that pass by the ankle on their way into the foot. The tibial nerve runs behind the medial malleolus. Another nerve crosses in front of the ankle on its way to top of the foot. There is also a nerve that passes along the outer edge of the ankle. The nerves on the front and outer edge of the ankle control the muscles in this area, and they give sensation to the top and outside edge of the foot.

Blood Vessels

The ankle gets blood from nearby arteries that pass by the ankle on their way to the foot. The dorsalis pedis runs in front of the ankle to the top of the foot. (You can feel your pulse where this artery runs in the middle of the top of the foot.) Another large artery, called the posterior tibial artery, runs behind the medial malleolus. It sends smaller blood vessels to the inside edge of the ankle joint. Other less important arteries entering the foot from other directions also supply blood to the ankle.

Guide to Bunionette (Tailor’s Bunion)

bunionette is similar to a bunion, but it develops on the outside of the foot. It is sometimes referred to as a tailor’s bunion because tailors once sat cross-legged all day with the outside edge of their feet rubbing on the ground. This produced a pressure area and callus at the bottom of the fifth toe.

Anatomy

Where does a bunionette develop?

A bunionette occurs over the area of the foot where the small toe connects to the foot. This area is called themetatarsophalangeal joint, or MTP joint. The metatarsals are the long bones of the foot. The phalanges are the small bones in each toe. The big toe has two phalanges, and the other toes have three phalanges each.

Causes

How does a bunionette develop?

Today a bunionette is most likely caused by an abnormal bump over the end of the fifth metatarsal (the metatarsal head) rubbing on shoes that are too narrow. Some people’s feet widen as they grow older, until the foot splays. This can cause a bunion on one side of the foot and a bunionette on the other if they continue to wear shoes that are too narrow. The constant pressure produces a callus and a thickening of the tissues over the bump, leading to a painful knob on the outside of the foot.

Many problems that occur in the feet are the result of abnormal pressure or rubbing. One way of understanding what happens in the foot as a result of abnormal pressure is to view the foot simply. Essentially a foot is made up of hard bone covered by soft tissue that we then put a shoe on top of. Most of the symptoms that develop over time are because the skin and soft tissue are caught between the hard bone on the inside and the hard shoe on the outside.

Any prominence, or bump, in the bone will make the situation even worse over the bump. Skin responds to constant rubbing and pressure by forming a callus. The soft tissues underneath the skin respond to the constant pressure and rubbing by growing thicker. Both the thick callus and the thick soft tissues under it are irritated and painful. The answer to decreasing the pain is to remove the pressure. The pressure can be reduced from the outside by changing the pressure from the shoes. The pressure can be reduced from the inside by surgically removing any bony prominence.

Symptoms

What do bunionettes feel like?

The symptoms of a bunionette include pain and difficulty buying shoes that will not cause pain around the deformity. The swelling in the area causes a visible bump that some people find unsightly.

Diagnosis

How do doctors identify a bunionette?

The diagnosis of a bunionette is usually obvious on physical examination. X-rays may help to see if the foot has splayed and will help decide what needs to be done if surgery is necessary later.

Plantar Fasciitis (Heel Pain)

Plantar fasciitis is a painful condition affecting the bottom of the foot. It is a common cause of heel pain and is sometimes called a heel spur. Plantar fasciitis is the correct term to use when there is active inflammation. Plantar fasciosis is more accurate when there is no inflammation but chronic degeneration instead. Acute plantar fasciitis is defined as inflammation of the origin of the plantar fascia and fascial structures around the area. Plantar fasciitis or fasciosis is usually just on one side. In about 30 per cent of all cases, both feet are affected.

Anatomy

Where is the plantar fascia, and what does it do?

The plantar fascia (also known as the plantar aponeurosis) is a thick band of connective tissue. It runs from the front of the heel bone (calcaneus) to the ball of the foot. This dense strip of tissue helps support the arch of the foot by acting something like the string on an archer’s bow. It is the source of the painful condition plantar fasciitis.

The plantar fascia is made up of collagen fibers oriented in a lengthwise direction from toes to heel (or heel to toes). There are three separate parts: the medial component (closest to the big toe), the central component, and the lateral component (on the little toe side). The central portion is the largest and most prominent.

Both the plantar fascia and the Achilles’ tendon attach to the calcaneus. The connections are separate in the adult foot. Although they function separately, there is an indirect relationship. If the toes are pulled back toward the face, the plantar fascia tightens up. This position is very painful for someone with plantar fasciitis. Force generated in the Achilles’ tendon increases the strain on the plantar fascia. This is called the windlass mechanism. Later, we’ll discuss how this mechanism is used to treat plantar fasciitis with stretching and night splints.

Causes

How does plantar fasciitis develop?

Plantar fasciitis can come from a number of underlying causes. Finding the precise reason for the heel pain is sometimes difficult.

As you can imagine, when the foot is on the ground a tremendous amount of force (the full weight of the body) is concentrated on the plantar fascia. This force stretches the plantar fascia as the arch of the foot tries to flatten from the weight of your body. This is just how the string on a bow is stretched by the force of the bow trying to straighten. This leads to stress on the plantar fascia where it attaches to the heel bone. Small tears of the fascia can result. These tears are normally repaired by the body.

As this process of injury and repair repeats itself over and over again, a bone spur (a pointed outgrowth of the bone) sometimes forms as the body’s response to try to firmly attach the fascia to the heelbone. This appears on an X-ray of the foot as a heel spur. Bone spurs occur along with plantar fasciitis but they are not the cause of the problem.

As we age, the very important fat pad that makes up the fleshy portion of the heel becomes thinner and degenerates(starts to break down). This can lead to inadequate padding on the heel. With less of a protective pad on the heel, there is a reduced amount of shock absorption. These are additional factors that might lead to plantar fasciitis.

Some physicians feel that the small nerves that travel under the plantar fascia on their way to the forefoot become irritated and may contribute to the pain. But some studies have been able to show that pain from compression of the nerve is different from plantar fasciitis pain. In many cases, the actual source of the painful heel may not be defined clearly.

Other factors that may contribute to the development of plantar fasciitis include obesity, trauma, weak plantar flexor muscles, excessive foot pronation (flat foot) or other alignment problems in the foot and/or ankle, and poor footwear.

Symptoms

What does plantar fasciitis feel like?

The symptoms of plantar fasciitis include pain along the inside edge of the heel near the arch of the foot. The pain is worse when weight is placed on the foot especially after a long period of rest or inactivity. This is usually most pronounced in the morning when the foot is first placed on the floor. This symptom called first-step pain is typical of plantar fasciitis.

Prolonged standing can also increase the painful symptoms. It may feel better after activity but most patients report increased pain by the end of the day. Pressing on this part of the heel causes tenderness. Pulling the toes back toward the face can be very painful.

Diagnosis

How do doctors diagnose the condition?

The diagnosis of plantar fasciitis is generally made during the history and physical examination. There are several conditions that can cause heel pain, and plantar fasciitis must be distinguished from these conditions. Pain can be referred to the heel and foot from other areas of the body such as the low back, hip, knee, and/or ankle. Special tests to challenge these areas are performed to help confirm the problem is truly coming from the plantar fascia.

An X-ray may be ordered to rule out a stress fracture of the heel bone and to see if a bone spur is present that is large enough to cause problems. Other helpful imaging studies include bone scans, MRI, and ultrasound. Ultrasonographic exam may be favored as it is quick, less expensive, and does not expose you to radiation.

Laboratory investigation may be necessary in some cases to rule out a systemic illness causing the heel pain, such as rheumatoid arthritis, Reiter’s syndrome, or ankylosing spondylitis. These are diseases that affect the entire body but may show up at first as pain in the heel

Osteochondritis Dissecans

Osteochondritis dissecans (OCD) is a problem that causes pain and stiffness of the ankle joint. It can occur in all age groups. Most cases of OCD usually follow a twisting injury to the ankle and are actually fractures of the joint surface.

Anatomy

Where does OCD develop?

The talus is one of the large bones in the back part of the foot that helps form the ankle joint. The area where OCD occurs is located at the top of the talus. Depending on how the ankle is injured, the problem can occur on the side of the talus closest to the other foot or on the outside part.

The top of the talus is part of the joint and is covered with articular cartilage, the white, slippery material that covers all joint surfaces. On the talus, this covering is about one-eighth of an inch thick. This material allows the bones of the joint to slide against each other without much friction. Right below the articular cartilage is the bone of the talus.

Causes

How does OCD develop?

The cause of most cases of OCD are thought to be actual chip-type fractures. These fractures occur with severe ankle sprains. Which side of the talus the chip is on depends on how the ankle was twisted during the initial injury.

The chip fracture can vary in size and severity. If the bone underneath the cartilage is crushed or cracked and the articular cartilage is intact, the fragment is less likely to move. If the articular cartilage is broken as well, the bone fragment may move out of position, or displace, making healing less likely and later problems more likely.

Because the bone chip is separated from the rest of the talus, the blood vessels traveling to the fragment through the bone of the talus are torn, and the blood supply of the bone fragment is lost. If the fragment displaces, these blood vessels cannot grow back. The fragment loses its blood supply and actually dies. This makes healing less likely.

There is some evidence that the twisting injury may not cause a chip fracture initially. However, it may injure the bone’s blood supply, leading to an area of the bone actually dying. This may explain some cases of OCD that appear without a well-defined history of a recent serious twisting injury.

Symptoms

What does OCD feel like?

Initially, OCD behaves like any other ankle sprain injury. You will feel swelling and pain and have difficulty placing weight on the ankle. No special symptoms suggest a chip fracture has occurred inside the joint. X-rays are the best way to determine whether a chip fracture has occurred.

Later, continued problems with the fragment may cause swelling and a generalized ache in the ankle. You may also feel a catching sensation with the ankle in certain positions. This is because the chip can get caught in the ankle joint as it moves, causing pain and the sensation of catching.

Diagnosis

How will the doctor know it’s OCD?

The diagnosis of OCD may be suggested by the history and physical examination. X-rays of the ankle will usually show a problem on the top of the talus (sometimes called the talar dome). Special tests such as a computerized tomography (CT) or a magnetic resonance imaging (MRI) scan may be necessary to determine the full extent of the area involved.

Morton’s Neuroma

Interdigital neuroma (sometimes called a Morton’s neuroma) is the medical term for a painful growth in the forefoot. The pain is most commonly felt between the third and fourth toes but can also occur in the area between the second and third toes. The exact cause of this problem is not clear. Some studies suggest that it is due to swelling, scarring, or a noncancerous tumor in one of the small nerves of the foot. The symptoms seem to be caused by irritation of the nerve that runs in the space between each toe.

Anatomy

What part of the foot is involved?

The nerves of the foot run into the forefoot and out to the toes between the long metatarsal bones of the feet. Each nerve splits at the end of the metatarsal bone and continues out to the end of the toe. Each nerve ending supplies feeling to two different toes. The interdigital neuroma occurs in the nerve just before it divides into the two branches, the area under the ball of the foot. A neuroma is formed by the swelling or thickening in this part of the nerve.

Causes

Why does the condition develop?

It is not entirely understood why an interdigital neuroma forms. Most likely, it results from repeated injury to the nerve in this area. Many theories have been put forth as to the cause of the chronic injury, but none has been proven.

The most common cause of pain is thought to be irritation on the nerve. The chronic nerve irritation is believed to cause the nerve to scar and thicken, creating the neuroma. Many foot surgeons feel that the problem may arise because the metatarsal bones squeeze in on the nerve, and the ligament that joins the two bones irritates, orentraps, the nerve. Entrapment of the nerve is thought to lead to the chronic irritation and pain.

Symptoms

What does an interdigital neuroma feel like?

The neuroma usually causes pain in the ball of the foot when weight is placed on the foot. Many people with this condition report feeling a painful catching sensation while walking, and many report sharp pains that radiate out to the two toes where the nerve ends. You may feel swelling between the toes or a sensation similar to having a rock in your shoe. This can feel like electric shocks, similar to hitting the funny bone on your elbow.

Diagnosis

How will my doctor know it’s an interdigital neuroma?

The diagnosis is usually made on history and physical examination alone. X-rays are only useful to make sure the pain is not coming from something else. In some confusing cases, an injection of lidocaine and cortisone into the area may help decide if the diagnosis of an interdigital neuroma is correct. This treatment should result in a reduction of symptoms temporarily.

Hallux Rigidus

Hallux rigidus is a degenerative type of arthritis that affects the large joint at the base of the big toe. Degenerative arthritis results from wear and tear on the joint surface over time. The condition may follow an injury to the joint or, in some cases, may arise without a well-defined injury.

Anatomy

Where does hallux rigidus occur?

The joint at the base of the big toe is called the metatarsophalangeal, or MTP, joint. Like any other joint in the body, the joint is covered with articular cartilage, a slick, shiny covering on the end of the bone. If this material is injured, it begins a slow process of wearing out, or degeneration. The articular surface can wear away until raw bone rubs against raw bone.

Bone spurs form around the joint as part of the degenerative process. The spurs, or bony outgrowths, may restrict the motion in the joint, especially the ability of the toe to bend upward when the foot moves forward.

Causes

Why do I have this problem?

Doctors remain uncertain about the true cause of hallux rigidus. Many surgeons feel that, in many cases, the condition begins with an injury to the articular cartilage lining the joint, such as from stubbing the big toe. The injury sets in motion a degenerative process that may last for years before symptoms occur that need treatment.

The condition can occur in younger adults but most often affects those who are 50 years old or older. Women seem to develop this problem more often than men. There may be a hereditary factor since two-thirds of patients have a positive family history. Patients who have other family members with hallux rigidus tend to have the problem in both feet (bilateral).

Other cases of hallux rigidus seem to arise without any type of serious injury. This suggests that there may be other reasons for the development of the condition. Minor differences in the anatomy of the foot may make it more likely that certain individuals develop hallux rigidus. This could be a slight change in the shape of the end of the bone (e.g., flatter than normal or oddly-shaped). The fascia (connective tissue) under the foot may be contracted (tight) increasing pressure on the MTP joint. These minor abnormalities may increase the stress that is placed on the joint while walking. Over many years, this may add up to degenerative arthritis of the joint.

Symptoms

What does hallux rigidus feel like?

The degeneration causes two problems–pain and loss of motion in the MTP joint. Without the ability of the MTP to move enough to allow the foot to roll through a full step, walking can become painful and difficult. Pain is most noticeable just before toe-off. Pain is increased when wearing shoes that have elevated heels. Bone spurs that develop with this condition can also put pressure on nearby nerves, causing numbness along the inside edge of the big toe.

Diagnosis

How do doctors identify the problem?

Diagnosis is usually apparent on physical examination, but X-rays are usually required to appreciate the extent of the degeneration and bone spur formation. X-rays also show the shape of the metatarsal head, amount of joint space, and presence of cartilage loss. This information can help direct treatment. MRIs or CT scans are only needed when the X-rays come back normal but some type of lesion is suspected.

Shin Splints

Pain along the front or inside edge of the shinbone (tibia) is commonly referred to as shin splints. The problem is common in athletes who run and jump. It is usually caused by doing too much, too quickly. The runner with this condition typically reports a recent change in training, such as increasing the usual pace, adding distance, or changing running surfaces. People who haven’t run for awhile are especially prone to shin splints after they first get started, especially when they run downhill. Shin splints on the front of the tibia are called anterior shin splintsPosterior shin splints cause pain along the inside edge of the lower leg.

Anatomy

What parts of the leg are involved?

The lower leg is made up of two bones. The shinbone is the larger of the two bones. It is called the tibia. The small, thin bone that runs alongside the tibia from the knee to the ankle is the fibula.

The tibia and fibula provide a connecting point for several muscles that move the foot. The main muscle that bends the foot upward connects on the front (anterior) of the tibia. It is called the anterior tibialis. The posterior tibialis, which pulls the foot down and in, attaches along the back (posterior) and inside edge of the tibia. Together, the anterior and posterior tibialis muscles are called the tibialis muscles.

The tibialis muscles have tiny fibers that fasten the muscle to the bony surface of the tibia. This bony covering, or membrane, is called the periosteum (peri means around, and osteum means bone).

Causes

Why do I have shin splints?

Shin splints usually result from overuse. Repeated movements of the foot can cause damage where the tibialis muscles attach to the tibia. Soon the edge of the muscles may begin to pull away from the bone. The injured muscle and the bone covering (the periosteum) become inflamed.

Overuse commonly happens after changes in training. Increasing running speed and distance and running on hard or angled surfaces can contribute to overuse. Overuse can also occur from running in flimsy footwear or in shoes with soles that are worn out.

Anterior shin splints tend to affect people who take up a new activity, such as jogging, sprinting, or playing sports that require quick starts and stops. The unfamiliar forces place a heavy strain on the anterior tibialis muscle, causing it to become irritated and inflamed. This commonly happens when people who aren’t regular runners decide to go on a long jog. The anterior tibialis muscle must work hard to control the landing of the forefoot with each stride. Running downhill puts even more demands on this muscle in order to keep the forefoot from slapping down. People who run on the balls of their feet or who run in shoes with poor shock absorption also tend to get anterior shin splints.

Posterior shin splints are generally caused by imbalances in the leg and foot. Muscle imbalances from tight calf muscles can cause this condition. Imbalances in foot alignment, such as having flat arches (called pronation), can also cause posterior shin splints. As the foot flattens out with each step, the posterior tibialis muscle gets stretched, causing it to repeatedly tug on its attachment to the tibia. The posterior tibialis muscle attachment eventually becomes damaged, leading to pain and inflammation along the inside edge of the lower leg.

A stress fracture in the tibia is a serious problem that at first may have the same symptoms as shin splints. A stress fracture is a crack in a weakened area of bone. Continual stresses from running on hard surfaces or from heavy strain in the tibialis muscles can weaken and eventually fracture the tibia. People with shin pain who try to work through it sometimes end up developing a stress fracture in the tibia.

A concerning complication of shin splints is compartment syndrome. Compartment syndrome is a condition where pressure from muscle damage and swelling builds up inside a section, or compartment, within the body. There are four compartments in the lower limb. As the pressure builds in the compartment, the small blood vessels (calledcapillaries) that supply blood to the muscles in the compartment are squeezed shut. This happens when the pressure in the compartment is higher than the blood pressure that keeps the small blood vessels open. When the muscle loses its blood supply it begins to ache, like a muscle cramp.

If the pressure continues to rise, it can squeeze the larger blood vessels and nerves as well. Patients may feel coldness, numbness, and swelling in the lower leg and foot. If pressure builds up and is not treated, it can cause serious tissue damage in the leg and foot.

Symptoms

What do shin splints feel like?

Dull, aching pain is felt where the involved tibialis muscle attaches to the tibia. Redness and swelling can also occur in this area. Tenderness is felt where the muscle attaches to the bone.

Anterior shin splints are usually felt on the front of the tibia, especially when using the anterior tibialis muscle to bend your foot upward.

Posterior shin splints produce symptoms along the inside edge of the lower leg. Small bumps may also be felt along the edge of the tibia in this area.

Symptoms of shin splints generally get worse with activity and ease with rest. Pain may be worse when you first get up after sleeping. The sore tibialis muscle shortens while you rest, and it stretches painfully when you put weight on your foot.

Diagnosis

How will my doctor know if I have shin splints?

The diagnosis of shin splints is usually made using your history and physical examination. The doctor may ask you questions about your training schedule and footwear. The doctor may also want to know whether you’ve recently begun a new sport that requires running or jumping.

The physical examination lets the doctor see exactly where your leg hurts. The doctor will probably move your ankle in different positions and have you hold your foot against the doctor’s pressure. By stretching the tibialis muscles and by feeling where these muscles attach on the tibia, the doctor can begin to tell where the problem is.

X-rays may be ordered to make sure you don’t have a stress fracture. However, recent stress injuries may not show up on X-ray for the first few weeks. In these cases, a bone scan may be ordered. A bone scan involves injecting tracers into your blood stream. The tracers then show up on special X-rays of your leg. The tracers build up in areas of extra stress to bone tissue. The extra stress can be caused by a stress fracture or an inflamed periosteum (bony covering). This condition is called periostitis.

Your doctor may also order a magnetic resonance imaging (MRI) scan. An MRI scan is a special imaging test that uses magnetic waves to create pictures of your body in slices. The MRI scan shows tendons as well as bones. It also shows abnormal swelling or scar tissue. An MRI is painless and requires no needles or injections.

A test for measuring pressure in the sore leg may be needed if you have symptoms of compartment syndrome. Pressures within the tissues of the leg are checked before and after exercise to see if exercise causes the

Cuboid Syndrome

Cuboid syndrome is a condition characterized by subluxation (partial dislocation) of the cuboid bone in the foot (figure 1).

The foot comprises of many small bones, one of which is the cuboid (figure 1). The cuboid bone is situated at the outer aspect of the mid-foot and is connected to adjacent bones via strong connective tissue forming joints. These joints provide outer foot stability and allow movement to take place.

During weight bearing activity, certain movements of the foot and ankle and contraction of certain muscles of the lower leg and foot (e.g. peroneus longus), stress is placed on the cuboid bone and surrounding soft tissue. If these forces are excessive and beyond what the bone and surrounding soft tissue can withstand, tearing of the supportive connective tissue may occur. This may allow the cuboid bone to sublux or partially move out of its normal alignment relative to the adjacent foot bones. When this occurs, the condition is known as cuboid syndrome.

Causes of cuboid syndrome

Cuboid syndrome may develop due to excessive traction on the cuboid due to repetitive contraction of the peroneus longus muscle (figure 2). This may occur in association with Peroneus Longus Tendinopathy. Cuboid syndrome may also develop following a Sprained Ankle whereby the foot and ankle are turned inward excessively (inversion), therefore causing damage to the connective tissue holding the cuboid bone in position. Most patients who develop this condition have excessively pronated feet (flat feet) although the condition may also be seen in those with lateral ankle instability. Cuboid syndrome is particularly common in ballet dancers and runners.

Signs and symptoms of cuboid syndrome

Patients with cuboid syndrome usually experience outer (lateral) foot pain that increases with weight bearing forces through the outer foot and may cause weakness during the push off phase of walking. Pain will often increase with twisting or unguarded movements or with running (particularly on hard surfaces and in unsupportive shoes). Pain may radiate into the sole of the foot, the front of the ankle or into the toes. In more severe cases, the patient may limp or walk with an abnormal gait (e.g. walk on their toes) in attempt to reduce stress on the cuboid bone. Pain may also increase on firm palpation of the cuboid bone. Rest from weight-bearing activity usually eases symptoms, unless significant inflammation is involved. Pain upon initial weight-bearing in the morning is also common.

Diagnosis of cuboid syndrome

A thorough subjective and objective examination from a physiotherapist or doctor is important to assist with diagnosis of cuboid syndrome. Investigations such as an X-ray, MRI, CT scan, bone scan or ultrasound may be required in some cases to confirm diagnosis and rule out other injuries.

Peroneal Tendonitis

roblems affecting the two peroneal tendons that lie behind the outer ankle bone (the lateral malleolus) are common in athletes. These problems mainly occur in the area where the two tendons glide within a fibrous tunnel behind the lateral malleolus.

Anatomy

What part of the ankle is involved?

The peroneals are two muscles and their tendons that lie along the outside of the lower leg bone (the fibula) and cross behind the lateral malleolus (the outer ankle bone). The term medial refers to a point closer to the center of the body. So the ankle bump on the inside edge of the ankle (closest to your other ankle) is the medial malleolus. The term lateral refers to structures furthest from the center. Major muscles that support the lateral part of the ankle are the peroneus longus and the peroneus brevis.

The tendons of these two muscles pass together in a groove behind the lateral malleolus. (Tendons attach muscles to bones.) The tendons are kept within the groove by a sheath that forms a tunnel around the tendons. The surface of the tunnel is reinforced by a band of tissue called a retinaculum. Contracting the peroneal muscles makes the tendons glide in the groove like a pulley. The pulley action causes the foot to point downward (plantarflexion) and outward(eversion).

The peroneus brevis tendon connects to a bump on the base of the fifth metatarsal. This spot can be felt midway down the outer edge of the foot.

The peroneus longus tendon lies behind and below the peroneus brevis tendon. It wraps down and under the foot by way of the cuboid bone, the outer tarsal bone just in front of the heelbone (the calcaneus). The peroneus longus tendon angles forward under the sole of the foot and connects to the bottom of the main bone of the big toe. This tendon stabilizes the arch of the foot when walking.

Causes

Why do I have this problem?

Peroneal tendon problems mostly occur where the tendons glide within the pulley behind the lateral malleolus. Their movement can cause irritation of the lining of the tendons. This condition is called tenosynovitis. The irritation can also occur after an ankle injury, such as a blow to the outside of the ankle or an ankle sprain.

Repetitive ankle motions in sports, such as running and jumping, can lead to wear and tear on the tendons inside the groove. A high arch puts extra tension on the peroneal tendons within the groove and has also been found to cause peroneal tendon problems.

Peroneal tendon problems commonly occur from an ankle sprain. During the typical inversion ankle sprain, the foot rolls in. This type of injury sprains or tears the ligaments that support the lateral part of the ankle. The forceful stretch on the peroneals when the foot rolls in can also cause a lengthwise tear in the peroneal tendons.

An inversion ankle sprain can also cause the peroneal tendons to momentarily slip out of the groove. This is calledsubluxation. Peroneal tendonitis often occurs during the recovery period after an ankle sprain. Because the ankle is unstable, the peroneals may need to work harder to give needed support to the damaged lateral ankle ligaments. The overwork sets them up for subluxation.

In some patients, a peroneal tendon problem is caused by degenerative changes in the tendons themselves rather than by inflammation around the tendons. The tendon itself becomes abnormal. Doctors call this condition tendonosis.

In tendonosis, the tendon becomes weakened. Tendons are made up of strands of a material called collagen. (If you think of a tendon as a nylon rope, the collagen is the nylon strands.) Degeneration in a tendon causes a loss of the normal arrangement of the collagen fibers that join together to form the tendon. Some of the individual strands of the tendon become jumbled due to the degeneration, some fibers break, and the tendon loses strength.

Over time, the tendon thickens as scar tissue tries to repair the damaged tendon. The area of tendonosis in the tendon is weaker than normal tendon. The weakened, degenerative tendon may tear. This usually causes a lengthwise split in the peroneal tendons rather than a rupture. These splits or tears are most common in the peroneus brevis tendon, probably because it lies in front of the peroneus longus. It is more vulnerable to friction because it rubs against the groove in the fibula bone.

Symptoms

What do peroneal tendon problems feel like?

Patients with peroneal tendon problems usually describe pain in the outer part of the ankle or just behind the lateral malleolus. This pain commonly worsens with activity and eases with rest. Patients may have swelling behind or under the lateral malleolus. They may notice more pain when pressure is applied along the tendons.

Diagnosis

How do doctors diagnose the condition?

The diagnosis of peroneal tendonitis is usually made by examination of the ankle. X-rays may be ordered to make sure there is no fracture or other problem. The physical examination helps determine where the tendons are inflamed, ruptured, or degenerated. The doctor will move your ankle into different positions. The peroneal tendons are checked by holding your foot up and out against the doctor’s downward pressure. Stretching the foot up and in can also be used test whether the tendons hurt.

Your doctor may order a magnetic resonance imaging (MRI) scan of your ankle. These images can show if there is abnormal swelling or scar tissue in the tendons. MRI scans can also show lengthwise tears in the tendons.

Sinus Tarsi Syndrome

Tarsal tunnel syndrome is a condition that occurs from abnormal pressure on a nerve in the foot. The condition is similar to carpal tunnel syndrome in the wrist. The condition is somewhat uncommon and can be difficult to diagnose.

Anatomy

Where is the tarsal tunnel, and what does it do?

The tibial nerve runs into the foot behind the medial malleolus, the bump on the inside of the ankle. As it enters the foot, the nerve runs under a band of fibrous tissue called the flexor retinaculum. The flexor retinaculum is a dense band of fibrous tissue that forms a sort of tunnel, or tube. Several tendons, as well as the nerve, artery, and veins that travel to the bottom of the foot pass through this tunnel. This tunnel is called the tarsal tunnel. The tarsal tunnel is made up of the bone of the ankle on one side and the thick band of the flexor retinaculum on the other side.

Causes

What causes tarsal tunnel syndrome?

In many cases, doctors aren’t sure what causes tarsal tunnel syndrome. Inflammation in the tissues around the tibial nerve may contribute to the problem by causing swelling in the tissues and pressure on the nerve.

Anything that takes up space in the tarsal tunnel can increase pressure in the area because the flexor retinaculum cannot stretch very much. This can occur from swollen varicose veins, a tumor (noncancerous) on the tibial nerve, and swelling caused by other conditions, such as diabetes. As pressure increases in the tarsal tunnel, the nerve is the most sensitive to the pressure and is squeezed against the flexor retinaculum. This causes problems in the nerve that may lead to symptoms of tarsal tunnel syndrome.

In the case of a nerve, the area of skin supplied by the nerve usually feels numb, and the muscles controlled by the nerve may become weak. Pain is sometimes felt near the area where the nerve is squeezed or pinched.

Symptoms

What does tarsal tunnel syndrome feel like?

Tarsal tunnel syndrome usually causes a vague pain in the sole of the foot. Most patients describe this pain as a burning or tingling sensation. The symptoms are typically made worse by activity, especially standing and walking for long periods. Symptoms are generally reduced by rest. You may feel pain if you touch your foot along the course of the nerve. If the condition becomes worse, your foot may feel numb and weak.

Diagnosis

How do doctors identify tarsal tunnel syndrome?

The diagnosis of tarsal tunnel syndrome begins with a complete history and physical examination. A Tinel’s sign may be present. This is a tingling sensation that shoots what feel like electric shocks into the foot when the skin above the nerve is tapped with a finger at the level of the irritation.

If more information is needed to make the diagnosis, a nerve conduction velocity (NCV) test may be suggested by your doctor. This test measures how fast nerve impulses travel along a nerve. If the test shows that the impulses are traveling slowly across the ankle, this may confirm a diagnosis of tarsal tunnel syndrome.

Flatfoot

Introduction

Adult acquired flatfoot deformity (AAFD) is a painful condition resulting from the collapse of the longitudinal(lengthwise) arch of the foot. As the name suggests, this condition is not present at birth or during childhood. It occurs after the skeleton is fully matured.

In the past it was referred to a posterior tibial tendon dysfunction (or insufficiency). But the name was changed because the condition really describes a wide range of flatfoot deformities. AAFD is most often seen in women between the ages of 40 and 60.

Anatomy

What parts of the foot are involved?

The skeleton of the foot begins with the talus, or ankle bone, that forms part of the ankle joint. The two bones of the lower leg, the large tibia and the smaller fibula, come together at the ankle joint to form a very stable structure.

The two bones that make up the back part of the foot (sometimes referred to as the hindfoot) are the talus and thecalcaneus, or heel bone. The talus is connected to the calcaneus at the subtalar joint. The ankle joint allows the foot to bend up and down. The subtalar joint allows the foot to rock from side to side.

Just down the foot from the ankle is a set of five bones called tarsal bones that work together as a group. These bones are unique in the way they fit together. There are multiple joints between the tarsal bones. When the foot is twisted in one direction by the muscles of the foot and leg, these bones lock together and form a very rigid structure. When they are twisted in the opposite direction, they become unlocked and allow the foot to conform to whatever surface the foot is contacting.

The tarsal bones are connected to the five long bones of the foot called the metatarsals. The two groups of bones are fairly rigidly connected, without much movement at the joints.

The large Achilles’ tendon is the most important tendon for walking, running, and jumping. It attaches the calf muscles to the heel bone to allow us to rise up on our toes. The posterior tibial tendon attaches one of the smaller muscles of the calf to the underside of the foot. This tendon helps support the arch and allows us to turn the foot inward. Failure of the posterior tibial tendon is a major problem in many cases of adult-acquired flatfoot deformity (AAFD).

The toes have tendons attached that bend the toes down (on the bottom of the toes) and straighten the toes (on the top of the toes). The anterior tibial tendon (tibialis anterior) allows us to raise the foot. Two tendons run behind the outer bump of the ankle (called the lateral malleolus) and help turn the foot outward.

Many small ligaments hold the bones of the foot together. Most of these ligaments form part of the joint capsulearound each of the joints of the foot. A joint capsule is a watertight sac that forms around all joints. It is made up of the ligaments around the joint and the soft tissues between the ligaments that fill in the gaps and form the sac.

The spring ligament complex is often involved in adult-acquired flatfoot. This group of ligaments supports thetalonavicular joint. The spring ligament complex works with the posterior tibial tendon and the plantar fascia to support and stabilize the longitudinal arch of the foot. Failure of the ligaments that support this arch can contribute to flatfoot deformity. Injury, laxity (looseness), or other dysfunction of the ligament and tendon structures can result in deformity of the foot and/or ankle resulting in AAFD.

Causes

What causes adult-acquired flatfoot deformity?

There are multiple factors contributing to the development of this problem. Damage to the nerves, ligaments, and/or tendons of the foot can cause subluxation (partial dislocation) of the subtalar or talonavicular joints. Bone fracture is a possible cause. The resulting joint deformity from any of these problems can lead to adult-acquired flatfoot deformity.

Dysfunction of the posterior tibial tendon has always been linked with adult-acquired flatfoot deformity (AAFD). The loss of active and passive pull of the tendon alters the normal biomechanics of the foot and ankle. The reasons for this can be many and varied as well. Diabetes, high blood pressure, and prolonged use of steroids are some of the more common causes of adult-acquired flatfoot deformity (AAFD) brought on by impairment of the posterior tibialis tendon. Overstretching or rupture of the tendon results in tendon and muscle imbalance in the foot leading to adult-acquired flatfoot deformity (AAFD).

Rheumatoid arthritis is one of the more common causes. About half of all adults with this type of arthritis will develop adult flatfoot deformity over time. In such cases, the condition is gradual and progressive.

Obesity has been linked with this condition. Loss of blood supply for any reason in the area of the posterior tibialis tendon is another factor. Other possible causes include bone fracture or dislocation, a torn or stretched tendon, or a neurologic condition causing weakness.

Symptoms

What does the condition feel like?

At first you may notice pain and swelling along the medial (big toe) side of the foot. This is where the posterior tibialis tendon travels from the back of the leg under the medial ankle bone to the foot. As the condition gets worse, tendon failure occurs and the pain gets worse. Some patients experience pain along the lateral (outside) edge of the foot, too.

You may find that your feet hurt at the end of the day or after long periods of standing. Some people with this condition have trouble rising up on their toes. They may be unable to participate fully in sports or other recreational activities.

Diagnosis

How do doctors diagnose the problem?

The history and physical examination are probably the most important tools the physician uses to diagnose this problem. The wear pattern on your shoes can offer some helpful clues. Muscle testing helps identify any areas of weakness or muscle impairment. This should be done in both the weight bearing and nonweight bearing positions.

A very effective test is the single heel raise. You will be asked to stand on one foot and rise up on your toes. You should be able to lift your heel off the ground easily while keeping the calcaneus (heel bone) in the middle with slightinversion (turned inward).

X-rays are often used to study the position, shape, and alignment of the bones in the feet and ankles. Magnetic resonance (MR) imaging is the imaging modality of choice for evaluating the posterior tibial tendon and spring ligament complex.

There are four stages of adult-acquired flatfoot deformity (AAFD). The severity of the deformity determines your stage. For example:

    • Stage I means there is a flatfoot position but without deformity. Pain and swelling from tendinitis is common in this stage. Stage II there is a change in the foot alignment. This means a deformity is starting to develop. The physician can still move the bones back into place manually (passively). Stage III adult-acquired flatfoot deformity (AAFD) tells us there is a

fixed

    deformity. This means the ankle is stiff or rigid and doesn’t move beyond a neutral (midline) position. Stage IV is characterized by deformity in the foot and the ankle. The deformity may be flexible or fixed. The joints often show signs of degenerative joint disease (arthritis).

 

Ankle Syndesmosis Injuries

A Patient’s Guide to Ankle Syndesmosis Injuries

Introduction

An ankle injury common to athletes is the ankle syndesmosis injury. This type of injury is sometimes called a high ankle sprain because it involves the ligaments above the ankle joint. In an ankle syndesmosis injury, at least one of the ligaments connecting the bottom ends of the tibia and fibula bones (the lower leg bones) is sprained. Recovering from even mild injuries of this type takes at least twice as long as from a typical ankle sprain.

Anatomy

What part of the ankle is involved?

syndesmosis is a joint where the rough edges of two bones are held together by thick connective ligaments. The connection of the lower leg bones, the tibia and fibula, is a syndesmosis. The tibia is the main bone of the lower leg. The fibula is the small, thin bone that runs down the outer edge of the tibia.

Only a few joints in the body are syndesmosis joints. In addition to the ankle syndesmosis (the connection of the tibia and fibula), syndesmosis joints are also located in the lower spine, where the top of the triangular-shaped sacrum bone fits between the pelvis bones.

Most joints in the body are synovial joints. Synovial joints are enclosed by a ligament capsule and contain a fluid, called synovium, that lubricates the joint. The ankle syndesmosis sits next to the ankle synovial joint, where the tibia meets the talus bone.

The ankle syndesmosis is supported and held together by three main ligaments. The ligament crossing just above the front of the ankle and connecting the tibia to the fibula is called the anterior inferior tibiofibular ligament (AITFL). The posterior fibular ligaments attach across the back of the tibia and fibula. These ligaments include the posterior inferior tibiofibular ligament (PITFL) and the transverse ligament. The interosseous ligament lies between the tibia and fibula. (Interosseous means between bones.) The interosseus ligament is a long sheet of connective tissue that connects the entire length of the tibia and fibula, from the knee to the ankle.

The syndesmosis ligaments hold the bottom ends of the tibia and fibula in place. This arrangement forms the upper surface of the ankle joint. The ankle joint is a hinge joint. The hinge is formed where the tibia and fibula sit above the talus bone. This connection is called a mortise and tenon, a stable connection that woodworkers and craftsmen routinely use to create strong and stable constructions.

Causes

Why do I have this problem?

Doctors do not completely understand how syndesmosis injuries occur, though they appear to happen most often when the foot is forced upward and outward. Such injuries frequently happen in high-level football players, although snow skiers also account for a high percentage of syndesmosis injuries.

Many times, a patient describes having sprained an ankle. It isn’t until later, when standard treatments for the ankle sprain aren’t helping, that further testing shows a syndesmosis injury.

An ankle syndesmosis injury involves a sprain of one or more of the ligaments that support the ankle syndesmosis. A ligament is made up of multiple strands of connective tissue, similar to a nylon rope. A sprain stretches or tears the ligaments. Minor sprains only stretch the ligament. A tear may be either a complete tear of all the strands of the ligament or a partial tear of only some of the strands. The ligament is weakened by the injury. How much it is weakened depends on the degree of the sprain.

Mild syndesmosis sprains usually involve a stretch or slight tear in only one of the ligaments making up the syndesmosis. Moderate tears of the ankle syndesmosis may lead to ankle joint instability, which make the ankle mortise loose. In severe tears of the ligaments, the ends of the tibia and fibula actually spread apart. This condition is called diastasis.

Symptoms

What does an ankle syndesmosis injury feel like?

Syndesmosis injuries are the most severe sprains of the foot and ankle. They also cause the most problems for people trying to get back to normal activity, especially athletes hoping to resume intense running, cutting, and jumping.

Mild to moderate syndesmosis sprains may at first feel like a routine sprained ankle. Symptoms include pain and swelling on the outside of the ankle.

If the problem has been ongoing, patients may have pain due to an unstable ankle joint. They may feel vague pain around the ankle. Attempts to turn or twist the injured foot may cause sharp pain in the ankle joint. Pain may radiate upward along the side of the lower leg. And the ankle may feel weak, like it can’t be trusted to hold steady, even during routine activities.

Diagnosis

How do doctors diagnose the condition?

The diagnosis of syndesmosis injuries is usually made by examining the ankle. The doctor moves your ankle in different positions in order to check the ligaments and tendons around the ankle. The syndesmosis is stressed by turning the ankle outward while holding the lower leg still. Another test, called thesqueeze test, is done by grabbing the calf just above the ankle joint and squeezing it. Pain with this test is a hallmark of a syndesmosis injury.

Tenderness can usually be pinpointed over the front ankle ligaments (the AITFL) and possibly over the posterior fibular ligaments (the PITFL and transverse ligaments).

X-rays are used to determine the severity of the syndesmosis injury. Stress X-rays are done to see if the tibia and fibula splay apart. The stress X-ray is done with the foot angled outward. An enlarged gap between the tibia and fibula indicates a diastasis (mentioned earlier). X-rays are also used to check for other problems, such as a fracture in the leg or ankle.

Doctors usually suspect a syndesmosis injury when patients have severe pain that lingers after what was thought to be a routine ankle sprain.

Freiberg’s Disease

This is a rare disease characterised by osteonecrosis of the second metatarsal head, most commonly seen in teenage girls.[1] It was first described in 1914 by Alfred H. Freiberg.[2]

It is difficult to ascertain the true incidence of Freiberg’s disease, as many cases may resolve spontaneously before treatment has been sought. Most series in the literature have small numbers.

It occurs during the growth spurt at puberty. Most commonly it is found in young females with a male:female ratio of 1:5.[3] It is also more common in patients whose first metatarsal is shorter than the second metatarsal, which increases the weight on the second metatarsal head.

 

The initial injury, as described by Freiberg, was thought to be repetitive stress with microfractures at the junction of the metaphysis and the growth plate. The fractures deprive the epiphysis of adequate circulation, and there is avascular necrosis of the metatarsal head.

Although the second metatarsal is most often affected, the third metatarsal may also be involved; involvement of the fourth or fifth is rare.

However, despite much subsequent research, the true aetiology remains elusive – it’s like to be a combination of vascular compromise, genetic predisposition and altered biomechanics.[4] It is thought to belong to a group of related diseases involving growth disturbances of the epiphysis or apophysis, collectively termed the osteochondroses.

Other osteochondroses include:

  • Köhler’s bone disease – tarsal navicular bone
  • Panner’s disease – capitulum[5]
  • Blount’s disease – proximal tibia
  • Sever’s disease – calcaneus
  • Sinding-Larsen and Johansson syndrome – patella
  • Pain in the forefoot, usually localised to the head of the second metatarsal.
  • Usually this is associated with physical activity.
  • Wearing high-heeled shoes makes it worse.
  • There may also be localised swelling and stiffness in the metatarsophalangeal joint.
  • A limp may be visible.

Tarsal Tunnel Syndrome

Tarsal tunnel syndrome is a condition that occurs from abnormal pressure on a nerve in the foot. The condition is similar to carpal tunnel syndrome in the wrist. The condition is somewhat uncommon and can be difficult to diagnose.

Anatomy

Where is the tarsal tunnel, and what does it do?

The tibial nerve runs into the foot behind the medial malleolus, the bump on the inside of the ankle. As it enters the foot, the nerve runs under a band of fibrous tissue called the flexor retinaculum. The flexor retinaculum is a dense band of fibrous tissue that forms a sort of tunnel, or tube. Several tendons, as well as the nerve, artery, and veins that travel to the bottom of the foot pass through this tunnel. This tunnel is called the tarsal tunnel. The tarsal tunnel is made up of the bone of the ankle on one side and the thick band of the flexor retinaculum on the other side.

Causes

What causes tarsal tunnel syndrome?

In many cases, doctors aren’t sure what causes tarsal tunnel syndrome. Inflammation in the tissues around the tibial nerve may contribute to the problem by causing swelling in the tissues and pressure on the nerve.

Anything that takes up space in the tarsal tunnel can increase pressure in the area because the flexor retinaculum cannot stretch very much. This can occur from swollen varicose veins, a tumor (noncancerous) on the tibial nerve, and swelling caused by other conditions, such as diabetes. As pressure increases in the tarsal tunnel, the nerve is the most sensitive to the pressure and is squeezed against the flexor retinaculum. This causes problems in the nerve that may lead to symptoms of tarsal tunnel syndrome.

In the case of a nerve, the area of skin supplied by the nerve usually feels numb, and the muscles controlled by the nerve may become weak. Pain is sometimes felt near the area where the nerve is squeezed or pinched.

Symptoms

What does tarsal tunnel syndrome feel like?

Tarsal tunnel syndrome usually causes a vague pain in the sole of the foot. Most patients describe this pain as a burning or tingling sensation. The symptoms are typically made worse by activity, especially standing and walking for long periods. Symptoms are generally reduced by rest. You may feel pain if you touch your foot along the course of the nerve. If the condition becomes worse, your foot may feel numb and weak.

Diagnosis

How do doctors identify tarsal tunnel syndrome?

The diagnosis of tarsal tunnel syndrome begins with a complete history and physical examination. A Tinel’s sign may be present. This is a tingling sensation that shoots what feel like electric shocks into the foot when the skin above the nerve is tapped with a finger at the level of the irritation.

If more information is needed to make the diagnosis, a nerve conduction velocity (NCV) test may be suggested by your doctor. This test measures how fast nerve impulses travel along a nerve. If the test shows that the impulses are traveling slowly across the ankle, this may confirm a diagnosis of tarsal tunnel syndrome.

Ingrown Toenail

Ingrown toenail is a condition that most commonly affects the hallux, or big toe. This condition usually results when pressure from improper shoe wear and improper care of the toenails leads to pain and overgrowth of the tissue at the side of the nail.

Anatomy

How does a toenail normally grow?

The toenail (and any other nail) is produced by the nail’s germinal matrix (special nail-generating tissue) and grows forward to the end of the toe. Most of us have lost either a fingernail or toenail and watched as the nail regrew slowly over several months. The area under the nail that attaches the nail to the toe is called the sterile matrix. The sterile matrix doesn’t produce the nail. The sterile matrix just attaches the nail to the toe. On either side of the nail is an area called the nail groove, where the skin of the toe meets the nail matrix and the edge of the toenail.

Causes

How does the problem develop?

In the case of the ingrown toenail, the nail groove begins to disappear, probably due to pressure from ill fitting shoes. The chronic pressure of the nail edge rubbing against the nail groove causes irritation and swelling of the surrounding skin. If the condition continues, hypertrophy, or overgrowth, of the tissue, leads to permanent changes in the tissue. These changes only make the situation worse. Eventually, an infection can occur in the area, leading to even more pain and swelling. Improper trimming of the toenail can also cause problems. If the corner of the toenail is not allowed to grow out past the skin at the end of the nail groove, it may dig into the skin. This makes the pressure from the shoe even more painful.

Symptoms

What does an ingrown toenail feel like?

The primary symptom of an ingrown toenail is pain. The toe is red and painful to the touch, and it can be difficult to wear shoes. If infection is present, pus may drain from the area as well.

Diagnosis

How will my doctor confirm it’s an ingrown toenail?

Diagnosis is generally easily made on examination. No X-rays or tests are usually required, unless your doctor suspects that the infection may have spread to the bone.

Diseases

Foot & Ankle
Foot & Ankle

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