The anatomy and biomechanics of the Achilles tendon

The Achilles is the largest tendon in the body, and it attaches the gastrocnemius muscle and the soleus muscle ( the muscles in the back of the calf) to the calcaneus (heel bone).  It transmits the force of the muscles through a relatively short lever arm, and is subjected to very large tensile forces, sometimes exceeding 1000 pounds.

The junction of the Achilles and the calcaneus is a complex of tissues that includes fibrocartilage on the back of the calcaneus where it touches the tendon, and sometimes a fibrocartilagenous surface on the corresponding front-facing surface of the tendon. The retrocalcaneal bursa lubricates the motion of these two agains each other. Collagen fibers run from the tendon into the bone to anchor it, and continue around onto the bottom of the foot, forming a single functional unit with the plantar fascia.

Achilles tendon - a common area for pain

Due to the incredible loads and demands placed on the Achilles' tendon, it is a common site of problems, and it is the most common ruptured tendon in the human body.

Most patients develop gradually increasing symptoms in the Achilles, but some still nothing until the moment they're tendon ruptures.  Chronic Achilles problems are the type which develops slowly and progressively.  These problems cause heel pain, pain in the back of the foot with running, pain with working out on inclined treadmills or running uphill, lumps in the Achilles' tendon, and a king and swelling in the tendon or on the heel bone where the Achilles' tendon inserts.

Achilles rupture can occur high up in the back of the leg, where the muscle and tendon joint, or it can occur in the tendon right at the heel bone or just above the heel bone.

Treatment without surgery

Treatment of chronic Achilles problems involves a multifaceted approach.  Simply stated, the goal of treatment is to reduce the factors that are leading to injury and damage, and promote the factors that are leading to natural healing.  This involves improving the biomechanics of the tendon to reduce the tensile loads the tendon is subjected to.  Physical therapy, medicines, orthotics, and other treatments are the mainstay.  Rest or changes to the workout pattern are vital.  General fitness measures, such as weight loss, flexibility, and nutrition need to be considered as well.  Patients need to understand that the gradual, progressive changes that lead to the problem did not happen overnight, and thus, the gradual progress of healing that will lead eventually to a healthy tendon takes time as well.

If patients apply a program of General fitness, weight loss, flexibility, activity modification, rest, and appropriate nutrition, virtually any Achilles' tendon problem will respond to treatment in time.

In reality, these goals can be very difficult for patients to achieve.  Many have been suffering for years and have been trying various therapeutic programs often on for months and months, without lasting relief.  For these patients surgery should be considered.

What about surgery?

Surgical treatment of Achilles' tendon problems is very successful, but the main thing to remember is that it takes a long time to recover from any Achilles problem, whether it is treated surgically or without surgery.  Patients need to set aside several weeks during which the tendon is immobilized, although most patients are able to walk within days of surgery.  Following this, return to sports must be delayed by at least three months, and most patients take six months or a year to achieve their maximum benefit following Achilles' tendon surgery.

See more on partial rupture of the Achilles