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Overview

The Achilles tendon is the largest and most vulnerable tendon in the body. It joins the gastrocnemius (calf) and the soleus muscles of the lower leg to heel of the foot. The gastrocnemius muscle crosses the knee, the ankle, and the subtalar joints and can create stress and tension in the Achilles tendon . Tendons are strong, but not very flexible so they can only so far before they get inflammed and tear or rupture.

Causes
The Achilles tendon is a strong bands of fibrous connective tissue that attaches the calf muscle to the heel bone. When the muscle contracts, the tendon transmits the power of this contraction to the heel bone, producing movement. The Achilles tendon ruptures because the load applied to it is greater than the tendon's ability to withstand that load. This usually occurs as a result of a sudden, quick movement where there is a forceful stretch of the tendon or a contraction of the muscles eg: jumping, sprinting, or pushing off to serve in tennis. This occurs most often in sports that require a lot of stopping and starting (acceleration-deceleration sports) such as tennis, basketball, netball and squash. The Achilles tendon is on average 15cm in length. Most ruptures occur 2-6cm above where the tendon inserts into the heel bone. This is the narrowest portion of the Achilles tendon and is also the area with the poorest blood supply. achilles tendon rupture is most common when the muscles and tendon have not been adequately stretched and warmed up prior to exercise, or when the muscles are fatigued. the Achilles tendon has a poor blood supply, which makes it susceptible to injury and slow to heal after injury. During exercise the amount of blood able to travel to the tendon is decreased, further increasing the risk of rupture. Most experts agree that there are no warning signs of an impending rupture. However, frequent episodes of Achilles tendonitis (tendon inflammation) can weaken the tendon and make it more susceptible to rupture.

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
Laboratory studies usually are not necessary in evaluating and diagnosing an Achilles tendon rupture or injury, although evaluation may help to rule out some of the other possibilities in the differential diagnosis. Plain radiography. Radiographs are more useful for ruling out other injuries than for ruling in Achilles tendon ruptures. Ultrasonography of the leg and thigh can help to evaluate the possibility of deep venous thrombosis and also can be used to rule out a Baker cyst, in experienced hands, ultrasonography can identify a ruptured Achilles tendon or the signs of tendinosis. Magnetic resonance imaging (MRI). MRI can facilitate definitive diagnosis of a disrupted tendon and can be used to distinguish between paratenonitis, tendinosis, and bursitis.

Non Surgical Treatment
Nonsurgical method is generally undertaken in individuals who are old, inactive, and at high-risk for surgery. Other individuals who should not undergo surgery are those who have a wound infection/ulcer around the heel area. A large group of patients who may not be candidates for surgery include those with diabetes, those with poor blood supply to the foot, patients with nerve problems in the foot, and those who may not comply with rehabilitation. Nonsurgical management involves application of a short leg cast to the affected leg, with the ankle in a slightly flexed position. Maintaining the ankle in this position helps appose the tendons and improves healing. The leg is placed in a cast for six to 10 weeks and no movement of the ankle is allowed. Walking is allowed on the cast after a period of four to six weeks. When the cast is removed, a small heel lift is inserted in the shoe to permit better support for the ankle for an additional two to four weeks. Following this, physical therapy is recommended. The advantages of a nonsurgical approach are no risk of a wound infection or breakdown of skin and no risk of nerve injury. The disadvantages of the nonsurgical approach includes a slightly higher risk of Achilles tendon rupture and the surgery is much more complex if indeed a repair is necessary in future. In addition, the recuperative period after the nonsurgical approach is more prolonged.


Surgical Treatment
Unlike other diseases of the Achilles tendon such as tendonitis or bursitis, Achilles tendon rupture is usually treated with surgical repair. The surgery consists of making a small incision in the back part of the leg, and using sutures to re-attach the two ends of the ruptured tendon. Depending on the condition of the ends of the ruptured tendon and the amount of separation, the surgeon may use other tendons to reinforce the repair. After the surgery, the leg will be immobilized for 6-8 weeks in a walking boot, cast, brace, or splint. Following this time period, patients work with a physical therapist to gradually regain their range of motion and strength. Return to full activity can take quite a long time, usually between 6 months and 1 year.

Prevention
To help prevent an Achilles tendon injury, it is a good practice to perform stretching and warm-up exercises before any participating in any activities. Gradually increase the intensity and length of time of activity. Muscle conditioning may help to strengthen the muscles in the body.