What is the Achilles tendon?

The Achilles tendon is the largest, strongest tendon in the human body. Tendons are long, tough cords of tissue that connect muscle to bone. The Achilles tendon is located in the back of the heel and connects the heel bone to the calf muscle. It helps a person walk, run and jump. The Achilles tendon is able to endure stress, but sometimes injury can occur to the tendon when it is overly stressed.

What is Achilles tendinitis?

Overuse of the Achilles tendon may cause the tendon to swell, become irritated, inflamed, and painful. This is Achilles tendinitis. It is a common sports injury that is related to running, but it can happen to anyone who puts a lot of stress on their feet (e.g., basketball players and dancers). If one does not get treatment for Achilles tendinitis, the problem can become chronic (long-term) and make it difficult to walk.

What is an Achilles tendon rupture?

In an Achilles tendon rupture, the tendon that connects the heel bone to the calf muscle tears and the fibers separate. This happens mostly to people between the ages of 30 and 50, and usually is caused by sports activity.

What causes Achilles tendinitis?

Achilles tendinitis is caused by a great deal of stress on the feet. It is a common athletic injury. Things that can cause tendinitis include:

  • Pushing the body too fast and too soon
  • A sudden increase in activity
  • Sports that have quick starts and stops
  • Poor fitting shoes/bad footwear
  • Injury to the Achilles tendon
  • Running or exercising on uneven ground
  • Running uphill
  • Tight calf muscles
  • Bone spur (extra bone growth in the heel that rubs the tendon and causes pain)
  • Flat arches, feet that roll in (overpronation), and weak calf muscles
  • Not warming up before exercising

What are the symptoms of Achilles tendinitis?

Common symptoms of Achilles tendinitis include:

  • Weakness in the leg
  • Slight pain in the lower leg above the heel after activity
  • Feeling of stiffness in the leg that usually appears in the morning and lessens throughout the day
  • Bad pain the day after exercising
  • Pain as you climb stairs or go uphill
  • Swelling in the area of the Achilles tendon  

What causes an Achilles tendon rupture?

The causes of an Achilles tendon rupture are very similar to those of Achilles tendinitis. Causes include:

  • Running uphill;
  • Running on a hard surface;
  • Quickly changing speeds from walking to running;
  • Playing sports that cause you to quickly start and stop.

What are the symptoms of Achilles tendon rupture?

Symptoms of Achilles tendon rupture include the following:

  • A pop or snap when the tendon tears
  • Severe pain in back of the ankle, making it difficult to walk
  • Swelling and discoloration
  • Tenderness
  • Inability to rise on the toes
  • A gap in the back of the ankle where the tendon ends separated after the tear.

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