The Achilles tendon is the single strongest tendon in the human body. The primary function of the Achilles tendon is to transmit the power of the calf to the foot enabling walking and running. If it has to do with upright, bipedal motion, the Achilles tendon is a part of that activity. Occasionally the Achilles tendon looses the ability to keep up with us and the tendon becomes inflamed resulting in Achilles tendonitis. This article discusses the onset, symptoms and treatment of Achilles tendonitis. Achilles tendon ruptures are also discussed.

Acute Achilles tendonitis
Acute Achilles tendonitis (also known as Albert's Disease) typically has a abrupt onset with moderate pain 2-3 cm proximal to the tendons' insertion on the back of the heel. Many individuals who suffer from acute Achilles tendonitis can describe an injury or single event that initiated the pain. Symptoms of acute Achilles tendonitis occur at the beginning of an activity and are typically described as sharp pain. As the activity continues and the Achilles tendon 'warms up', the Achilles tendon pain begins to feel a bit better. With excessive use, the Achilles tendon again becomes painful at the end of activity. For example, runners with Achilles tendonitis experience pain as they begin their run. The pain subsides during their run only to recur near the end of their normal running distance.

Chronic Achilles tendonitis
Chronic Achilles tendonitis differs from acute Achilles tendonitis in the location of pain. While acute Achilles tendonitis is specific to the body of the tendon, chronic Achilles tendonitis tends to be found more on the back of the heel at the insertion of the Achilles tendon. Due to the location of the pain found in chronic Achilles tendonitis, this condition is sometimes called insertional Achilles tendonitis. Chronic Achilles tendonitis can also cause hypertrophy (enlargement) of the posterior heel, and in a limited number of cases, enlargement of the tendon itself. In years gone by when pump high heels were popular, the term pump bump was applied to this condition. Pump high heels had a tendency to irritate the posterior heel contributing to tendonitis and bursitis. Bursitis often occurs in conjunction with chronic Achilles tendonitis and is called retrocalcaneal bursitis.

In cases of chronic Achilles tendonitis it's important to differentiate between pain strictly due to the pull of the Achilles tendon and pain due to the enlargement of the posterior heel rubbing against the shoe. The difference between Achilles tendonitis and a pump bump can easily be understood by evaluating the pain while barefoot (suggestive of Achilles tendonitis) compared to pain while wearing shoes with an enclosed heel (pump bump). It's not unusual to find both conditions simultaneously.

This picture shows the back of a right heel, the outside of the ankle and a few of the small toes. The red dotted line outlines the Achilles tendon. This is the area within the tendon where we are most likely to find an acute tear of the Achilles tendon or tendonitis. The red circle shows the area where the Achilles tendon inserts into the calcaneus and is the location of chronic Achilles tendonitis. This are will often become hypertrophied (enlarged) as the result of spurring that forms on the posterior heel at the insertion of the tendon. The red circle is also the area where we would find pain associated with retrocalcaneal bursitis. The blue area is on the outside, or lateral aspect of the heel. The blue area is where we would find the symptoms of Haglund's Deformity or a pump bump. You can see that a Haglund's Deformity is usually found on the posterior lateral heel (blue) while insertional Achilles tendonitis is central to the Achilles tendon.

Treatment of acute and chronic Achilles tendonitis
Knowing that the single greatest contributing factor to acute and chronic Achilles tendonitis is equinus (see the biomechanics section below for more information on equinus), we know that we need to weaken the calf muscle to allow the Achilles tendon an opportunity to heal. This can be done by elevating the heel with heel lifts or by wearing a subtle high heeled pair of shoes. Inflammation of the tendon can be calmed by ice, both before and after activities. Anti-inflammatory medications, casting or ultrasound treatment can also be used. Steroid injections are typically not used to treat Achilles tendonitis since injecting the tendon has a tendency to weaken the tendon resulting in a possible rupture.

In cases of chronic Achilles tendonitis, patients who do not respond to heel lifts and anti-inflammatory medications require a lengthening procedure of the Achilles tendon with or without a partial resection of the posterior heel. In cases with minimal hypertrophy of the heel, lengthening of the tendon will suffice. Lengthening of the Achilles tendon may be performed through three 0.5cm incisions but does require a period of casting. Full recovery may take 6-18 months. Endoscopic techniques are also available in a limited number of cases, correcting equinus with a procedure called an endoscopic gastrocnemius recession.