Tearing of the extensor tendon of the finger


The extensor tendon of a finger can tear due to an accident or degenerative changes. Such a tear is not uncommon, especially in sports accidents. A distinction is made between a tear at the distal phalanx of the finger and a complete tear of the tendon close to the palm.


The most common occurrence of a finger tendon tear is on the fourth finger, the ring finger. The cause may be a longstanding tendon inflammation (tendosynovitis) due to a rheumatic disease. However, the extensor tendon can also tear during traumas or when the finger is stretched more, for example during ball sports or when sleeping.


Initially, patients complain of a significant reduction in strength when the affected finger is extended. The active extension in the affected joint is then no longer possible. Since there is normally a balance between the muscles on the finger, the flexor tendon predominates in the case of an extensor tendon tear.

This makes the injury clearly visible to the outside, as the affected finger is in an excessive bending position. As a rule, the tear is accompanied by a strong, short, shooting pain. Then there is swelling and possibly bleeding on the affected finger.

Particularly in patients with a chronic rheumatic disease, the pain is often absent, so that the actual time of injury is often not remembered. This article may also be of interest to you:

  • Pain in the little finger

At the moment of the injury, there may be a brief shooting and stabbing pain in the finger. This is caused by the tear and the snapping back of the tendon in the tissue.

Often no further pain occurs after the injury. However, the injury may cause small concomitant injuries in the tissue, causing bruising and swelling. Due to the irritation in the tissue, the tear of the extensor tendon can be painful under pressure a few days after the injury.

In the further course, however, the tear does not cause pain. There is only an extension deficit and a reduction in strength, which is why many affected persons consult a doctor only late. When the extensor tendon of the finger tears, local inflammatory processes rarely occur. An injury in the tissue can always be accompanied by concomitant injuries, bleeding, pain, swelling, redness and restricted movement. However, this local inflammation usually subsides within a few days.


In most cases, the clinical picture of the injury is sufficient to make a tentative diagnosis. The affected finger is in an extreme bending position, active extension of the finger is no longer possible. However, passive extension by the doctor should still be possible if the joint is not affected.

This is an important diagnostic distinction, as the therapy depends on it. In some cases, the anamnesis about the course of the accident can contribute to finding a diagnosis. In order to rule out the joint condition and bone fractures, an X-ray can be taken.

However, the tendons and muscles of the fingers are not visible here. These can be examined by means of a tomography (magnetic resonance imaging (MRT) or computer tomography (CT)). In some cases, it is also possible to view the tendons of the fingers using ultrasound.

In addition, all other fingers of the hand, as well as the hand’s blood circulation and sensitivity should also be examined during the clinical examination. In this way, severe vascular damage or nerve damage can be excluded. If only a small part of the extensor tendon on the end phalanx of the finger is torn, surgical treatment is usually not necessary.

A splint treatment is usually sufficient. However, this should not be removed prematurely in order to achieve a good final result. As a rule, conservative treatment takes 6 weeks.

If the joint is intact and the tendon is completely torn so that healing without surgery is impossible, the extensor tendon of the finger can be surgically repaired. First, the torn tendons are visualized intraoperatively and their torn ends are refreshed. The further procedure depends on the torn tendon:

  • If the tendon of the little finger is affected, its end close to the body is connected to the tendon of the ring finger.

This procedure is relatively simple and allows early mobilisation. – If the extensor tendons of the little finger and ring finger are severed, another tendon, the tendon of the index finger base joint, is severed. Its ends are then sutured so that the function can be restored.

  • If the tendon of the middle finger is also torn, it is sewn to the side of another extensor tendon of the index finger. – If the long tendon of the thumb is affected, a tendon of the index finger can also be used. – In the rare case that all extensor tendons of a hand are torn, it is possible to use the two flexor tendons of the 3rd and 4th finger (middle and ring finger).

The tendons must be completely removed and then sutured to the extensor part of the arm. Then the suture is applied to the torn extensor tendons. Taping the finger is a therapeutic alternative to conservative treatment with a splint.

A tape bandage is applied along the length of the finger on the extensor side to splint and stabilize the finger. The flexibility and mobility of the finger are significantly greater during treatment with a tape bandage than with splinting. However, complete immobilization cannot be guaranteed.

If the tendon is partially torn, the tape bandage can be used. In the case of a complete tear, however, treatment with the splint should be the main focus of attention, at least during the first few weeks. As a preventive measure, an elastic tape bandage can be worn on the fingers during sports to prevent tendon injuries. This stabilises the fingers and leads to a more conscious exercise of movements, which is associated with a reduced risk of injury.