Torn Achilles tendon

Every year, about 16,000 Achilles tendons tear, especially under athletic stress.


The Achilles tendon (= tendo calcaneus (Achilles)) is the supposedly strongest tendon in the human body. It is located at the calcaneus tuber (= heel bone) and combines the end tendons of the three calf muscles as the end tendon of the musculus triceps surae (calf muscle). In the case of an Achilles tendon rupture, which is caused by degenerative damage, it is a complete severing of the tendon, usually as a result of direct or indirect force.

Development of a torn Achilles tendon

In addition to the wear and tear factors, which are due to the poorer blood supply to the tendon tissue with increasing age and the purely mechanical explanations for the occurrence of an Achilles tendon tear, there are also biological aspects which will be briefly explained at this point. With regard to these biological aspects, patients are particularly at risk, who are particularly susceptible to the occurrence of ruptures of the Achilles tendon on both sides. A rupture of the Achilles tendon can also occur with good physical condition.

This is particularly the case if the tendon fibres were not warmed up sufficiently during the warm-up phase, or if so-called lactic acid fatigue occurs due to a low PH value. In both cases, the Achilles tendon is mechanically overstressed and tearing is encouraged. – take certain drugs, such as cortisone or cytostatics.

Antibiotics from the group of gyrase inhibitors (fluoroquinolones) such as ciprofloxacin (Ciprobay) or ofloxacin (Tarivid) are also said to increase the risk. They are used to treat cystitis (inflammation of the bladder), but also diseases of the nasopharynx. – suffer from diabetes (= sugar disease).


A rupture of the Achilles tendon usually occurs spontaneously, without the person affected having previously felt pain or other symptoms. In almost 90% of the cases, it is a rupture that occurs when the tendon is subjected to heavy sporting strain. Therefore, most of those affected are also young men who are active in sports.

Nevertheless, in most cases there were minor injuries (micro-fractures) to the tendon beforehand, which reduced its resilience during the subsequent sporting activity. In addition, the tendon can be damaged by injuries, for example by a cut in the heel area. If this injury is very deep, the tendon can be completely severed.

Some drugs also affect the strength of the tendons in the body. Taking such drugs can therefore lead to an increased susceptibility to tendon ruptures of all kinds. Drugs that can promote tendon rupture include certain antibiotics (gyrase inhibitors), corticosteroids and immunosuppressants.

Although the Achilles tendon can withstand very strong mechanical stress, it can be subject to wear and tear due to age or illness. In addition, the Achilles tendon of athletically inactive people is less resilient because it is not used to stress and therefore yields more quickly when stress suddenly sets in. The signs of wear and tear also lead to reduced extensibility of the tendon.

In addition, the connective tissue fibres of which the tendon is made are partially damaged in this case, so that the structure of the tendon which provides support is no longer intact. All these factors can additionally promote a rupture of the Achilles tendon. The Achilles tendon as such is mechanically very resilient.

A maximum load capacity of up to 400 KP is assumed. The cause of an Achilles tendon rupture is usually favoured by wear and tear processes, which can be intensified by a possibly poor training condition. With such causes, the entire muscle and tendon apparatus is significantly less elastic, making the Achilles tendon rupture more likely.

As a result of maximum load (unexpectedly high force), for example when starting to sprint, when jumping off or coming up after a jump, when skiing or playing football, an Achilles tendon rupture can occur. As a rule, the Achilles tendon rupture is accompanied by a loud bang, the acoustic appearance of which can be compared to a whip cracking. Usually the Achilles tendon is then completely torn.

The Achilles tendon usually tears at the narrowest point. You can feel this point yourself: starting from the uppermost part of the heel bone (rear edge) you go up about 5cm. After a tear, plantar flexion (= active bending of the ankle joint, e.g. tip-toe flexion) of the foot is no longer possible due to the missing connection between the calf and the rear edge of the heel bone; the patient can no longer walk normally.