A torn extensor tendon can happen quickly, as it is only protected by a thin layer of skin and is a common hand injury. Our hands are very delicately built for their many uses and the tendons in our fingers in particular enable us to bend and extend our hands. In the following article, we clarify what is important to better understand the diagnosis.
Anatomy of the hand and tendons
Tendons are links between muscles and bones or their joints and play an important role in the transmission of force from muscles to bones . In our hands, too, for example, when we reach for our daily glass of water, the force of the tightening muscles in our forearm must be transferred to our finger bones. Two different types of tendons are responsible for this bending and extending movement of our fingers - namely flexor and extensor tendons. Everything you need to know about injuries to flexor tendons can be found here .
Our fingers each consist of three phalanges, which are connected by the base, middle and end joints. Above the phalanges, on the back of the hand, the extensor tendons run to the tips of the fingers. Here they are only protected by thin skin and are therefore often affected by hand injuries.
Extensor tendons (blue) run along the phalanges and cover the base, middle and end joints. Causes of an extensor tendon injury
There are many causes for an injured extensor tendon. Accidents with knives, broken glass or burns often lead to an extensor tendon injury, but so does a sudden overstretching of the finger, such as when catching a fall with the hand or when a ball hits the tip of the finger. Even piercing a cellophane wrapper of your favourite chocolate spread can spell doom for the extensor tendon.
Every gaping cut on the hand should be urgently examined by a doctor, as tendons are often injured as well. If left untreated, an extensor tendon injury can lead to arthrosis and deformity in the long term.
Symptoms: How do I recognise an injured extensor tendon?
A distinction is made between a closed and an open extensor tendon tear. A closed extensor tendon rupture is characterised by a sudden, but then decreasing pain , and above all by the fact that a finger limb hangs down and can no longer be actively stretched . A haematoma or swelling of the affected area is also common.
An open extensor tendon tear is when it is accompanied by an open visible wound. Here too, depending on the specific location of the tear, the corresponding phalanges remain bent . If the tendon is only partially torn, the affected fingers are usually slightly less flexed.
An extensor tendon rupture is often accompanied by concomitant injuries, which means that other symptoms may also occur.
Diagnosis of extensor tendon injuries
A characteristic feature of extensor tendon injuries is a tear directly at the joints, which is why the injury is often accompanied by an avulsion of small pieces of bone - this is called a bony tendon avulsion . In addition, other concomitant injuries often occur , such as a capsular tear. Ligaments, nerves and vessels can also be affected.
Such concomitant injuries must be clarified in detail during the medical examination . The course of the accident and the complaints are asked in a conversation and already provide important clues for the diagnosis. The individual joints are then checked for their function and mobility. In addition, an X-ray image provides information about possible bony injuries.
In bony tendon rupture , not only the tendon is torn but also small pieces of bone are affected. A distinction is made between three types of extensor tendon ruptures. The classification depends on the location of the injury . A close look at the flexion of the affected finger can already provide information about the location of the injury.
End joint
A typical sports injury is a tear of the extensor tendon at the end joint, i.e. at the tip of the finger, which is why it is sometimes called a "baseball finger". If you try to stretch the finger, the last phalanx of the finger remains bent - because of its shape, this injury is also called "hammer finger ".
Centre joint
A tear of the tendon at the middle joint of the finger can be easily overlooked at first. Often, a so-called buttonhole deformity develops in the course of time: If one tries to stretch the finger, the middle joint remains bent while the end joint is stretched, which visually resembles a button in a buttonhole.
Finger base joint
If the injury is directly at the base joint of the finger, the entire finger can no longer be actively extended.
The type of flexion of the injured finger often already shows where the tendon is torn. How is an injured extensor tendon treated?
If the diagnosis confirms the suspicion of an extensor tendon injury, the treatment method is considered: directly to the operating theatre or is a splint sufficient?
A splint often offers sufficiently good chances of healing, especially at the end phalanx . The finger end phalanx is immobilised in a so-called Stack splint for 6 weeks before exercises can be carefully started. During this time, it is essential that the other fingers continue to be moved in order to avoid stiffening of the hand. However, very few patients regain full range of motion in the injured joint. People who are absolutely dependent on full mobility, for example in music or handicrafts, should consider surgery.
In the case of closed injuries at the end joint, conservative treatment with the aid of a splint is often resorted to. Open injuries in the area of the middle and base joints are almost always operated on . The tendon stumps are sutured with needle and thread or - if this is not possible - another tendon is transplanted from the surrounding tissue. Some tendons are duplicated or not absolutely necessary for function, so they can be taken out and replace more important tendons if needed. Screws or wires may also be used if there is a bony avulsion.
In the case of open injuries, the tendon is sewn together during surgery. After the operation , the affected joint is immobilised with a splint . The further towards the palm of the hand the injury is, the shorter: about three weeks for the base joint, up to eight weeks for the end joint.
If the splint or the hand is cleaned, the finger must never hang freely in the air, but must always be supported or placed on a straight surface to avoid a new tear at all costs.
The optimal aftercare after an extensor tendon injury
In the follow-up treatment, the motto is: Healing by moving . Hand therapy and regular exercise at home are essential for successful healing. In the healing process, moderate movement also prevents various tissues from growing together and sticking together, such as tendons with their tendon sheaths.
Scars remain, especially in the case of open injuries or after an operation. These scars often lead to restrictions in the fine structures of the fingers. The more the scar is integrated into movement therapy during the healing process, the more supple it remains and contributes to natural movement after healing is complete.
How can the healing of the extensor tendon be supported?
If the extensor tendon injury is recognised quickly and treated appropriately depending on the type of injury, the prognosis for a complete recovery is positive. Here are a few tips on how you can support the healing process.
This way you can positively influence the healing of the extensor tendon:
Address complaints and uncertainties regarding the therapy plan directly with your medical and therapeutic team .Reliablyfollow the home programme set up by your therapist to avoid overload but also stiffening Your motivation contributes decisively to the success of the therapy!
More information about AnyHand for patients? More info Whether in sport or in everyday life - a torn extensor tendon can happen quickly. It is important that it is recognised quickly and treated according to the type of tear. Afterwards, optimal aftercare supports the healing process and prevents movement restrictions. This way, you are well on your way to being able to use your hand in everyday life again as soon as possible.
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Frequently asked questions
Where are the extensor tendons in the hand?
Our fingers have flexor and extensor tendons. The extensor tendons run above the phalanges, on the back of the hand to the fingertips. Since they are only protected by thin skin, they are susceptible to hand injuries.
What do extensor tendons do?
Like all tendons, extensor tendons are responsible for transmitting force from muscles to bones and joints. They are specifically responsible for the extension of our fingers and thus essential for the function of our hand in everyday life. If an extensor tendon is injured, the affected finger can no longer be actively extended.
What to do if you suspect an extensor tendon injury?
If an injured extensor tendon is suspected, the injury should definitely be clarified by a doctor, who can initiate a suitable therapy after examining the affected fingers.
How long is the splint worn for an extensor tendon injury?
In the case of exclusively conservative therapy, usually for injuries to the end joint, the splint is usually worn for about 6 weeks. A splint is also prescribed for immobilisation after surgery. Here the duration depends on the location of the injury: the further towards the palm of the hand the injury is, the shorter the splint usually has to be worn: about three weeks for the base joint, up to eight weeks for the end joint.
How long does it take for an extensor tendon tear to heal?
The healing time depends on the location and complexity of the extensor tendon injury. It usually takes at least 6 weeks, often longer, until the finger can be used again. You can try to contribute to a shorter and successful recovery through good aftercare and motivated cooperation.
This article deals with a health topic, but is not suitable for self-diagnosis or the selection of a suitable therapy. The individual case can only be reliably diagnosed by medical expertise.
Sources
Breier S, Diday-Nolle AP, Reiter Eigenheer A, Saur I. Hand Rehabilitation Volume 1 Fundamentals, Diseases. 3rd ed. Waldner-Nilsson B, editor. Heidelberg/Berlin: Springer-Verlag; 2013.
Schmidt H-M, Lanz U. Surgical Anatomy of the Hand. 1st ed. Stuttgart: Thieme; 1992.
Hirt B, Seyhan H, Wagner M, Zumhasch R. Anatomy and Biomechanics of the Hand. 3rd ed. Stuttgart, New York, Delhi, Rio: Thieme; 2015.
