The largest tendon in the body, the Achilles tendon is a cord connecting the calf muscles to the heel bone. Also called the ?cord of Achilles,? the tendon gets its name from the hero of Greek myth. According to legend, Achilles was invulnerable everywhere but his heel, where a poisoned arrow eventually felled him. Because the blood supply to the Achilles tendon lessens with age, the tendon becomes vulnerable to inflammation and rupture, a fact which makes it a true ?Achilles heel? for many older patients. Achilles tendon injuries are also common among athletes and those who engage in more physically demanding activity.
Causes
Your Achilles tendon helps you point your foot downward, rise on your toes and push off your foot as you walk. You rely on it virtually every time you move your foot. Rupture usually occurs in the section of the tendon located within 2 1/2 inches (about 6 centimeters) of the point where it attaches to the heel bone. This section may be predisposed to rupture because it gets less blood flow, which also may impair its ability to heal. Ruptures often are caused by a sudden increase in the amount of stress on your Achilles tendon. Common examples include increasing the intensity of sports participation, especially in sports that involve jumping, falling from a height, stepping into a hole.
Symptoms
Often the person feels a whip-like blow that is followed by weakness in the affected leg - usually he or she is not able to walk afterwards. At place where the tendon ruptured, a significant dent is palpable. Often the experienced physician can diagnose a ruptured Achilles tendon by way of clinical examination and special function tests. Imaging techniques, such as ultrasound and magnetic resonance imaging (MRI) allow for a more precise diagnosis.
Diagnosis
Some patients mistakenly believe the tendon is working if they can push the foot down, however, patients will usually be able to move the foot up and down while sitting because the other surrounding muscles and tendons are still intact. Trying to push up while standing and applying body weight to the foot will reveal the true weakness. Sensation and circulation to the foot and ankle will be normal. In addition, x-rays will be normal unless the Achilles injury involves pulling off (avulsion) of the bone on the calcaneus (heel bone). This is quite rare, occurring in only a small fraction of patients with Achilles injuries. Patients suffering this type of Achilles avulsion injury tend to be older with weaker bone.
Imaging Studies. Plain x-rays will be negative in patients who have suffered an Achilles tendon rupture. The rupture can be seen on ultrasound or MRI. However, these studies are not indicated for acute ruptures unless there is some uncertainty about the diagnosis. For chronic problems of the Achilles or ruptures that are old, an MRI may be very helpful.
Non Surgical Treatment
Not every torn Achilles tendon needs an operation. Recent studies have shown that even a conservative treatment, i.e. immobilizingt the leg can lead to satisfactory healing successes. This requires, however, that the patient is fitted with a cast (immobilization splint) and/or a special boot for a period of approximately 6 - 8 weeks. After that, the boot must be worn during the day for about two more weeks. An intensive physiotherapy will start after about six weeks to train the calf muscles so that the initial coordination can be restored. Running training on flat ground can be started again after another 10 - 12 weeks. Studies show that the danger of a recurring torn tendon is higher after a conservative treatment opposed to an operative treatment. Depending on the type of treatment, about 10 - 15 percent of those affected can expect at some point to again suffer from a tear of the Achilles tendon. Moreover, in the non-operated cases, we see more often a significant permanent weakness of the footprint, particularly restricting the ability to participate in sports.
Surgical Treatment
While it is possible to treat an Achilles tendon rupture without surgery, this is not ideal since the maximum strength of the muscle and tendon rarely returns. The reason is the ends of the tendon are ruptured in a very irregular manner, almost like the ends of a paint brush. As soon as the tendon ruptures, the calf muscle (gastrocnemius muscle) continues to pull on the tendon and the end of the ruptured tendon pulls back into the leg, which is called retraction. Once the tendon retracts, it is never possible to get sufficient strength back without surgery, because the muscle no longer functions at the correct biomechanical length and is now stretched out. There are patients for whom surgery cannot be performed, in particular, due to existing medical conditions that may add to potential for complications following surgery. For these patients, a specially designed boot that positions the foot correctly and takes the pressure and tension off the muscle and tendon is used. Most importantly, a cast is never used because it causes permanent shrinkage (atrophy) of the calf muscle. The special boot permits pressure on the foot with walking. The boot also has a hinge to permit movement of the ankle. Many studies of Achilles tendon ruptures have shown that this movement of the foot in the boot while walking is ideal for tendon healing. If surgery is not recommended, it is essential to obtain special tests to check that the ends of the tendon are lying next to each other so that healing can occur. The best test to do this is an ultrasound and not an MRI.
Prevention
Prevention centers on appropriate daily Achilles stretching and pre-activity warm-up. Maintain a continuous level of activity in your sport or work up gradually to full participation if you have been out of the sport for a period of time. Good overall muscle conditioning helps maintain a healthy tendon.