Achilles Tendon Problems

Patients with pain in the region of the Achilles tendon usually have a good long-term prognosis. Achilles tendon problems can affect anyone at any age. Nevertheless, runners have a 15 times greater risk of Achilles tendon rupture, and athletes have a 30 times greater risk of Achilles tendinopathy than do sedentary people.

Problems that affect the Achilles tendon are common among active, middle-aged people. These problems cause pain at the back of the calf. Severe symptoms may be the result of a complete rupture of the Achilles tendon.

What is the Achilles Tendon?

The Achilles tendon is a strong, fibrous band that connects the calf muscle to the heel. The calf is actually formed by two muscles, the underlying soleus and the thick outer gastrocnemius. Together, they form the gastroc-soleus muscle group. When they contract, they pull on the Achilles tendon, causing your foot to point down and helping you rise on your toes. This powerful muscle group helps when you sprint, jump, or climb. Several different problems can occur that affect the Achilles tendon, some rather minor and some quite severe.

What Causes Achilles Tendon Problems?

Overuse is the most common cause of Achilles tendon problems, especially in athletes. Initially, irritation of the outer covering of the tendon, called the paratenon, causes paratendonitis. Inflammation of the bursae in this region may also be present with paratendonitis. Most Achilles tendon problems are due to the following conditions:

Degeneration

As we age, our tendons can degenerate. Degeneration in the Achilles tendon shows up as a loss of the normal arrangement of the fibers of the tendon. Tendons are made up of strands of a material called collagen. Over time, some of the individual strands of the Achilles tendon become jumbled due to the degeneration, other fibers break, and the tendon loses strength.

Bursitis

Bursitis is an inflammation of the bursae that are designed to limit friction in the joints. The bursa behind the heel bone normally limits friction where the thick, fibrous Achilles tendon glides up and down behind the heel. There are actually two bursae in this region: the retrocalcaneal bursa, which lies between the posterior aspect of the calcaneus and the insertion of the Achilles tendon, and the Achilles bursa, which lies between the insertion of the Achilles tendon and the skin. Inflammation of one or both of these bursae can cause pain in and around the Achilles tendon.

Tendinopathy

Achilles tendinopathy may arise with increased training volume or intensity but may also arise insidiously. The athlete with overuse tendinopathy notices a gradual development of symptoms and typically complains of pain and morning stiffness after increasing activity level. Pain diminishes with walking about or applying heat (e.g. a hot shower). In most cases, Achilles tendon pain diminishes during training, only to recur several hours later.

Tendonosis

The healing process in the Achilles tendon causes it to become thickened as scar tissue tries to repair the tendon. This process can continue to the extent that a nodule forms within the tendon. This condition is called tendonosis. The area of tendonosis in the tendon is weaker than normal. The tendonosis sets the stage for the possibility of actual rupture of the Achilles tendon.

Partial Tear

A violent strain can cause a partial tear of the Achilles tendon. This can happen during a strong contraction of the muscle. Landing on the ground after a jump can force the foot upward and cause a patial tear of the Achilles tendon. The onset of pain is usually more sudden than that of tendinopathy and may be more disabling in the short term.

Achilles Tendon Rupture

In severe cases, the force of a violent strain may rupture the Achilles tendon. A sudden, severe pain in the Achilles region with marked disability suggests a complete rupture. The patient often reports hearing a 'shot'. In some instances, the rupture may be preceded by tendonosis, which renders the Achilles tendon weaker than normal.