Causes

Even though tendons are not very elastic, not every extreme strain causes a tendon to tear. First of all, tendons can be stretched/overstretched. However, if a certain tolerance limit of tensile strength is then exceeded, the rupture event occurs.

Depending on its severity, the tendon tears only partially or completely, possibly including a bone rupture. The causes of a ruptured tendon are variable. Since the tendons are closely related to their respective muscles, certain movement sequences or force effects are the main causes of a tendon lesion.

Sudden loads with extreme pressure and tension can lead to a torn tendon. In general, strong external forces, such as a blow to the tendon area, provoke a torn tendon. A tendon is also particularly susceptible if it is under tension at the time of the violent or forceful impact or if the load is oblique.

Certain factors or conditions can increase the risk of a tendon tear. These include, for example, the inevitable aging process, which causes a loss of elasticity of tendons throughout the body. Another risk factor is the fact that already damaged tendons are more susceptible and tendon rupture is more likely.

Such predamaging causes can be inflammatory processes or overloading. Overloading plays an important role, especially in sports. Often small lesions on the tendon, e.g. small partial tears, remain undetected and the risk of a complete tendon rupture increases further and further as the strain continues without regeneration time.

Apart from this creeping injury process, acute tendon ruptures can of course also occur in sports. Traumatic tendon ruptures are generally the most common. Not to be forgotten, however, are degenerative and inflammatory processes, which are considered a risk factor for a torn tendon.

A torn tendon can be present in various parts of our body. Typical manifestations are described below. In the upper extremity, the tendons of the shoulder region, forearm and hand are mainly affected.

Shoulder region and forearms

At the shoulder, a tendon tear of the supraspinatus tendon often occurs. The supraspinatus tendon is part of the important muscle of the shoulder joint of the same name, the supraspinatus muscle. Together with three other muscles, it forms the rotator cuff, which is crucial for the stability of the shoulder joint, since it is a muscle-secured joint.

In general, therefore, the rotator cuff is primarily affected by a torn tendon, but the long biceps tendon in the shoulder region can also rupture.However, the supraspinatus tendon is very susceptible to lesions due to its course. It passes between the bony acromion and the head of humerus and is attached to a specific bony process (tuberculum majus) of the humerus. This tightness can lead to a bottleneck syndrome, the so-called impingement syndrome, which can be associated with severe pain.

Further damage due to overloading or signs of wear and tear can weaken the supraspinatus tendon to such an extent that the tendon finally tears. It is therefore important to treat warning signals like an impingement syndrome to prevent a rupture of the tendon. Further down the arm, the tendons of the muscles of the forearm are popular manifestation sites of a torn tendon.

Since we have many muscles on the forearm that function both as extensors or flexors and are divided into superficial and deep muscle groups, it is too complex to explain each individual muscle now. What they have in common are the causative factors mentioned above that lead to a torn tendon. Sports such as weightlifting, gymnastics, wrestling, javelin throwing and shot put are also particularly dangerous.

The supraspinatus muscle belongs to the shoulder muscles and is part of the so-called rotator cuff, a group of muscles that together move and stabilize the shoulder joint. The supraspinatus muscle is primarily responsible for the external rotation and abduction (the lateral movement of the upper arm away from the body) of the upper arm. The supraspinatus tendon runs in the shoulder joint in the narrow space between the acromion and the head of humerus.

As a result, the tendon is exposed to strong mechanical stress, which can lead to a rupture due to chronic incorrect loading, the aging process or an accident. Often the symptoms develop only gradually over months or years. Patients often complain of pain when the arm is strained as well as of shooting pains at night.

An experienced orthopedist can suspect a supraspinatus tendon rupture with the help of a physical examination. However, the gold standard for final diagnosis is an MRI examination. Supraspinatus tendon rupture can be treated both conservatively (e.g. physiotherapy, pain therapy) and surgically.

The optimal solution should be found individually for each patient. The biceps muscle is located on the upper arm and is responsible for flexion in the elbow joint. In case of a biceps tendon rupture, either the long, upper or lower biceps tendon can be affected.

A rupture of the long biceps tendon (also known as a proximal rupture) is the most common form of biceps tendon rupture and usually occurs as a result of trivial accidents with chronic previous damage. A rupture of the long biceps tendon is usually relatively painless and the strength and function of the arm is only slightly limited. The biceps muscle appears as a muscle bulge above the elbow joint, so it slides down, so to speak.

The lower biceps tendon tears mainly in acute injuries, often in the context of sports injuries. It is accompanied by acute, stabbing pain. A large hematoma (bruise) is often formed.

The flexion in the elbow joint is limited, the outward rotation of the hand is usually no longer possible. In addition to the physical examination, an ultrasound examination can also be used diagnostically. If trauma is the cause of the biceps tendon rupture, an X-ray may be useful to exclude fractures.

A rupture of the long biceps tendon is usually treated conservatively with pain therapy and protection. A rupture of the short biceps tendon is always treated surgically. A rupture of the tendon can also occur in the crook of the arm.

This is the lower tendon of the biceps muscle, which starts at the upper arm and connects to the spoke of the forearm via the crook of the arm. The tear of the lower biceps tendon is rather rare and occurs mainly in acute injuries, especially among athletes. The rupture is very painful, often resulting in the formation of a bruise.

The flexion in the elbow joint is mostly weakened, the outward rotation of the hand is usually completely stopped. A reliable diagnosis is possible by means of MRI or ultrasound. Therapeutically, the tendon is surgically reattached.