According to the American Academy of Orthopaedic Surgeons, the Achilles tendon is the largest tendon in the human body and can withstand forces of 1,000 pounds or more. The Achilles tendon connects the calf muscles to the heel. When the calf muscles contract, the force is transferred to the heel via the Achilles tendon, and the heel is lifted and propelled forward. The Achilles tendon is also one of the most frequently injured tendons.
Anatomy and Function
The Achilles tendon connects the large muscles in the back of the lower leg, called the gastrocnemius, to the heel. The tendon is made of a thick fibrous band of connective tissue and is surrounded by a sheath which reduces friction. When the calf muscles contract to perform the movements of walking, running, jumping and standing on the toes, the force is transferred to the heel via the Achilles tendon. The Achilles tendon is also involved in the lowering of the heel during similar activities.
Types of Injuries
The Achilles tendon is one of the most often injured tendons of the body. Achilles tendon injuries generally are classified as tendinitis, tendinosis and rupture. Achilles tendonitis is an inflammation of the tendon itself and is rarely used as a diagnosis on its own. Achilles tendinosis indicates the existence of small tears to the surrounding sheath and is a more likely cause of pain. Often a physician will use the diagnosis of Achilles tendinopathy to indicate the presence of both tendinitis and tendinosis. A more dramatic injury is the Achilles tendon rupture, which involves a partial or complete tear of the Achilles tendon.
Symptoms
Morning stiffness and soreness during activities are common symptoms of Achilles tendinopathy. There may be soreness to the touch and mild, localized, swelling near the attachment of the Achilles to the heel. As the tendinopathy progresses, the stiffness and soreness will become more persistent and more severe.
An Achilles tendon rupture is an acute and abrupt injury. Often the athlete will describe the feeling of being kicked in the back of the calf and will be unable to control the movement of his foot. He will be unable to continue any activity.
Causes of Injury
Achilles tendinopathy is the result of overuse or over-training. Often, symptoms will appear with an increase in training mileage and/or intensity, introducing hill running or with repetitive jumping exercises. In some cases, poor or inappropriate footwear can contribute to tendinopathy. Achilles tendon ruptures tend to occur during activities requiring quick, explosive, changes in speed or direction, such as racquetball or basketball. According to the Mayo Clinic, men ages 30 to 40 are more likely to rupture an Achilles tendon.
Treatment
It is important to begin treatment of Achilles tendinopathy as soon as symptoms appear. Treatment of tendinopathy should involve rest from the offending activity and ice to control any swelling. Other forms of exercise, such as swimming and bicycle riding, should be implemented. Aggressive stretching should be avoided. If soreness does not resolve within two weeks, the athlete should see a physician.
An Achilles tendon rupture will require immediate treatment with either immobilization or surgical repair. Both approaches will require casting for about six weeks, followed by four to eight weeks of physical therapy. The physician and the athlete will decide which approach is appropriate on a case by case basis.
