Tendons link your muscles to your bones. They let your bones move as your muscles tighten and relax. Overuse, injury, aging and health conditions, such as arthritis, can damage your tendons. You can lessen the chances of tendon problems with a balanced exercise routine.
A tendon is a cord of strong, flexible tissue, similar to a rope. Tendons connect your muscles to your bones. Tendons let us move our limbs. They also help prevent muscle injury by absorbing some of the impact your muscles take when you run, jump or do other movements.
Your body contains thousands of tendons. You can find tendons from your head all the way down to your toes. The Achilles tendon, which connects your calf muscle to your heel bone, is the largest tendon in your body.
Tendons are highly resistant to tearing but aren’t stretchy. This means they can be easily injured when strained (stretched to point partial tearing of rope fibers) and may take a long time to heal.
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When you contract (squeeze) your muscle, your tendon pulls the attached bone, causing it to move. Tendons essentially work as levers to move your bones as your muscles contract and expand.
Tendons are stiffer than muscles and have great strength. For instance, the flexor tendons in your foot can handle more than eight times your body weight.
Tendons are located all over your body. For instance, tendons connect your muscles to your bones in your elbow, heel, knee, shoulder and wrist.
Tendons have different shapes and sizes depending on which muscles they’re attached to. Wider and shorter tendons usually connect to muscles that generate a lot of force. Thinner and longer tendons usually connect to muscles that perform more delicate movements.
Tendons are mostly collagen, one of the most abundant proteins in your body. Tendons also contain blood vessels and nerves.
Collagen fibers are flexible, strong and resistant to damage. A tendon’s structure is similar to a fiberoptic cable or a rope, with small collagen fibers arranged in bundles. This bundling reinforces the tendon and makes it stronger.
The collagen fibers in a tendon group into:
A tendon consists of:
Tendons connect your muscles to your bones at the following points:
The Sharpey fibers that are part of the tendon extend into the bone. The tendon of the hand and foot commonly slides through a connection called a reflection pulley that helps hold it in place. Small, fluid-filled pads called tendon bursae (plural of bursa) cushion tendons where they meet the bone.
Because tendons connect every muscle in your body, a wide range of injuries and disorders can cause tendon problems. Tendon issues are more common with age. As people get older, tendons become thinner, have less blood flow and accumulate microscopic damage to fibers that weaken the tendon.
Most commonly, disorders that affect the tendons include:
Strains: Strains occur when you tear, twist or pull a tendon. Tendon strains often happen in your arms and legs.
Tendonitis: Tendonitis results when your tendons become inflamed, usually due to repetitive activities, overuse or aging. Tendonitis (also called tendinitis) often occurs in your Achilles tendon, elbow, hip, knee, shoulder or thumb. The most common types of tendonitis include:
Tenosynovitis: Tenosynovitis occurs when tendinitis combines with inflammation of the tendon sheath. This commonly occurs in the hand and feet. Two common types are:
Other tendon disorders include:
Your healthcare provider will first do a physical examination. The key components are evaluating the joints connected by tendon, palpation of tendon for pain or defects, evaluating the tendons flexibility, and manual strength test. They may ask you to move the joints near your injured or inflamed tendon. You may experience pain when your provider moves or presses your tendon. Your tendon may also be swollen or warm. Your provider will also test your range of motion around your area of pain. Sometimes the areas around your joints may also feel stiff or weak.
Your healthcare provider may also use tests including:
Healthcare providers treat tendon problems in different ways, depending on the condition:
To help reduce your risk of tendon conditions:
Talk to a healthcare provider right away if you experience:
Without proper treatment, continued overuse of your tendons can lead to tendinosis. If you notice ongoing discomfort, talk to a provider about how to protect your tendons.
A note from Cleveland Clinic
Tendons connect your muscles to your bones. They let your bones move as your muscles tighten and relax. Conditions that affect your tendons include strains, tendinitis and tears, including rotator cuff tears and biceps tendon injuries. You can help keep your tendons healthy by monitoring your exercise habits and not pushing yourself past the point of pain. Be sure to see your healthcare provider if you have pain that doesn’t go away or comes back.
Last reviewed by a Cleveland Clinic medical professional on 08/10/2021.
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