Tendons are strong, flexible tissue bands connecting muscles to bones.
When you tighten your muscles, tendons shorten and pull on your bones to move your joints.
They are prone toinjuries like inflammation(swelling) from overuse, strains from overstretching, and tears.
Natastic / Getty Images
Natastic / Getty Images
Anatomy
Tendons are structures located at each end of a muscle.
These structures are flexible but not elastic, and may tear if you stretch them too far.
Tendons are composed ofcells called fibroblastsand an extracellular matrix (a supportive web connection of proteins and molecules).
Fibroblasts fuse to form bundles of fibers.
Groups of fiber bundles formfascicles, and groups of fascicles form your tendons.
The tendons' extracellular matrix is comprised of water, collagen, and other proteins.
Location
In some areas of the body, muscles attach directly to your bones.
Function of Tendons
Tendons attach muscles to bone.
Early treatment is key for the best outcome after this injury.
Common Tendon Injuries
Some tendons are more prone to injuries than others.
Commonly injured tendons include theAchilles tendon,tibialis posterior,patellar tendons,forearm extensors, and therotator cuff.
This movement occurs with every step you take throughout the day.
It also helps you stand up on your toes and jump.
Achilles tendinitisoften occurs with activities such as runningparticularly if you do too much, too fast.
It can also occur from tight calf muscles or frombone spursthat rub the tendon as you move.
This tendon supports your arch while you walk.
These injuries cause pain, swelling, and difficulty bearing weight on your foot.
Patellar tendinitis can occur from sports activities that include a lot of running and jumping.
This condition is sometimes called “jumper’s knee.
“Symptoms include pain at the front of your knee and eventually weakness.
The patellar tendon can alsotear.
This high-force injury occurs from trauma, such as a fall or landing from a jump.
Tendon tears can cause an audible “pop” or tearing sound.
You’ll also have severe pain, swelling, and difficulty straightening your knee.
If your patellar tendon tears completely, you’ll need surgery to repair it.
After surgery, you won’t be able to put pressure on your leg for several weeks.
Physical therapy is also key for regaining function after this surgery.
Full recovery takes six to 12 months.
Forearm Extensor Tendon
The forearm extensor muscles bend your wrist backward.
They share a tendon that attaches to the outside of your elbow.
The forearm extensor tendon is prone to overuse injurya condition called lateralepicondylitisor “tennis elbow.
It can also be treated with steroid injection orplatelet-rich plasma injection.
Very rarely,surgeryis required to repair damaged tissue with tennis elbow.
These muscles include thesupraspinatus,infraspinatus, teres minor, andsubscapularis.
Rotator cuff tendons are prone to tendinitis, as well as tears.
These injuries often develop over time from overuse activities, as tendons “fray” and become inflamed.
Tears are treated based on the extent of the injury.
Rotator cuff tearsare classified as “partial” or “full-thickness.
“Partial tears affect part of the tendon, while full-thickness tears mean that the tendon is torn completely.
Small tears in the rotator cuff tendons can be treated conservatively.
However, larger or complete tears oftenrequire surgery.
Full recovery from rotator cuff surgery often takes six to nine months.
Summary
Tendons are made of connective tissue that attaches muscles to bone.
These structures can be found on muscles located around the moveable joints in your body.
Tendons are prone to injury, including tendinitis and tendon tears.
Treatment for these injuries include rest, anti-inflammatory medications, physical therapy, and sometimes surgery.
If you suspect that you have a tendon injury, talk to your healthcare provider.
Early intervention can prevent more serious injuries from developing.
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