Your body is an amazing machine made up of many connected parts that work together to allow movement. A tendon, also known as a sinew, is a fibrous tissue that helps to facilitate this movement.1 Tendons join muscles to their corresponding bones. Without tendons, your muscles wouldn’t be able to make your bones move.
Tendons are sometimes confused with ligaments. Ligaments and tendons serve similar purposes, but in different ways. While tendons connect muscle to bone, ligaments connect bones to other bones.2
Your feet contain more than 100 muscles, tendons, and ligaments.3 These invisible structures work together to help you do your most important movement – walking.
Tendons have different jobs, depending on their location. If you have a foot injury, it can benefit you to know the types of tendons and where they exist in your feet. Injuries to tendons, such as tendinitis and tendinosis, are common, especially for athletes.
Here is an explanation of the types of tendons present in your feet – and their purposes.
Your Achilles tendon, also called your calcaneal tendon, is one of the most well-known tendons in the body. It is also the thickest and strongest. Your Achilles tendon runs from your lower calf to your heel, connecting your heel bone to your leg muscles. The main function of the Achilles tendon is the movement known as plantar flexion – moving the foot and ankle downward.5
Unfortunately, the Achilles tendon is the tendon most prone to injury.6 Achilles tendinitis is a common injury that includes symptoms of pain in the lower back of the leg. This is often caused by strenuous exercise, or by not exercising properly. Achilles tendinitis is not serious, and it usually heals within a day to six weeks.7
Achilles tendinosis is a more serious condition involving the degeneration of the Achilles tendon.8 It is often caused by a heel bone spur, which is a bone growth that can occur on the back of your heel. Surgery is sometimes required, but patients’ conditions often improve after physical therapy or other treatments.9
Achilles tendons are also susceptible to bursitis, which is inflammation in the fluid-filled sacs that cushion bones and tendons. Achilles tendon bursitis often occurs on the backside of the heel. Swelling and tenderness at the back of the heel are the main symptoms. Treatment involves stopping inflammation with medications, along with warm and cold compresses, and rest.10
Another problem that can occur is Achilles tendon enthesopathy.11 Achilles tendon enthesopathy is one of the main causes of pain in the back of the heel.12 Treatment is usually physical therapy, including stretching and heel lifts.13
Extensor Foot Tendons
Your extensor foot tendons connect muscle to bone on the top of your feet. The two main extensor foot tendons are the extensor hallucis longus and the extensor digitorum longus. These tendons help your extensor muscles pull your foot upwards, which is necessary for walking.14
Extensor tendinitis happens when the tendons on top of your foot become inflamed. Runners are often subject to this painful condition. Symptoms include aching and burning in the top of your foot, especially when you try to move your toes.15
Flexor Foot Tendons
Your flexor foot tendons are located on the bottom of your feet. These tendons help the flexor muscles to stabilize your toes.16 There are four flexor tendons: flexor hallucis longus, flexor hallucis brevis, flexor digitorum longus, and posterior tibialis. Ballet dancers often have cases of tendinitis in their flexor hallucis longus because of the repeated movements associated with ballet dancing.
Your feet have two peroneal tendons located just behind your ankle bone. These tendons’ job is to stabilize and protect your ankle. Injuries of the peroneal tendons can occur suddenly during exercise, or gradually due to high arches.17 Marathon runners are susceptible to peroneal tendinitis, or the more serious peroneal tendinosis.18
What to Do If You Have Tendinitis or Tendinosis of the Feet
Tendinitis is the inflammation of a tendon. The American Podiatric Medical Association (APMA) recommends treating tendinitis by icing the area and getting plenty of rest. If your foot tendinitis doesn’t feel better after a week, it’s time to visit a podiatrist. You are more likely to get tendinitis again once you’ve gotten it already. Take proper precautions, such as stretching before exercise, getting used to exercise gradually. and wearing proper shoes, to prevent repeated cases of tendinitis.19
Tendinosis occurs when a tendon’s collagen degenerates over time, making the tendon weaker.20 This can happen as a result of chronic tendinitis. Treatment for tendinosis varies according to severity and may include surgery in severe cases.21 Your podiatrist can examine you to see if you have tendinosis and recommend treatment options.
Your feet are responsible for many important tasks in your life. Without your tendons, your foot muscles wouldn’t be able to move. Tendons play an important role in foot health, so taking care of them should be a priority.