Some common complications of tendon repair include infection, the tendon rupturing and the repaired tendon sticking to nearby tissue.

Infection

An infection develops after about one in every 20 tendon repair operations. The risk of infection is highest if you damaged your hand where there were a lot of germs, such as a farm. Crushing injuries are also more likely to cause an infection.

Symptoms that may indicate your hand has developed an infection include:

• redness and swelling in your hand
• a feeling of tenderness or pain
• a high temperature (fever) of 38°C (100.4°F) or above

Contact your GP if you think you have developed an infection. Most infections can be successfully treated with antibiotics.

Repair failure

After about one in every 20 tendon repair operations, the repair fails and the affected tendon ruptures.

When this happens, it usually occurs soon after the operation, when the tendon is weakest. Tendon ruptures often happen in people who do not follow the advice about resting the affected tendon. Accidental trips, falls or suddenly catching your splint on an object can also rupture the tendon.

Sometimes, it is obvious you have ruptured the tendon because you notice a sudden snapping or ‘pinging’ sensation in your hand. However, you may not notice the tendon has ruptured until you discover that you cannot move your finger or fingers in the same way as before.

If you think your tendon has ruptured, contact your surgical team or hand therapist. Further surgery is usually required to repair the tendon.

Tendon adhesion

Tendon adhesion is a medical term which means the tendons have become stuck to surrounding tissue and have lost some of their range of movement.

This can cause loss of movement, which in most cases is minor. More serious cases of tendon adhesion require surgery to free the stuck tendon.

Contact your surgical team or hand therapist if you notice a reduction in your ability to move your hand while you recover from surgery.

Before the cut tendons in your hand are repaired, X-rays of your hand, wrist and forearm may be taken to check for things such as fragments of glass (if the tendon was cut by broken glass) or other damage, such as a fracture, that may also need to be repaired.

Tendon repair is not usually regarded as emergency surgery, but is generally carried out as quickly as possible after the injury – usually within a few days.

This is because the longer the tendons remain ruptured, the more scarring will develop on the end of the tendons. This could reduce the range of your hand movement after surgery.

Depending on the nature of your injury, you may be given antibiotics and a tetanus jab before surgery to prevent your hand from becoming infected.

Extensor tendon repair

Extensor tendon repair is usually performed under a regional anaesthetic. This is when an injection is used to make part of your body totally numb. For hand surgery, regional anaesthetic is injected into base of the neck or top of the shoulder to numb the whole arm.

If your tendon was damaged due to a wound, the wound will be thoroughly cleaned. An incision may be made in your hand to make the wound larger and the two ends of the ruptured tendon will be stitched together.

The wound will then be closed with stitches and a rigid splint (a support to protect the hand) made of plaster is usually fitted to stop you moving your hand and damaging the repaired tendons.

If nothing else has been damaged, extensor tendon repair surgery can take around 30 minutes to complete.

Flexor tendon repair

Flexor tendon repair is usually performed under a regional or general anaesthetic.

A tourniquet will be applied to your upper arm to stop the blood circulating and to make it easier to perform the operation safely. A tourniquet is like a blood pressure cuff used to constrict (squeeze) the arm and temporarily cut off the blood supply.

The surgeon will then extend the wound, or make an incision if there is no wound, to locate the damaged tendons. They will bring the two ends of the damaged tendon together, before stitching them to each other.

The wound in the hand is then closed with stitches and a rigid plaster splint usually applied to protect the repaired tendons.

A simple flexor tendon repair takes 45-60 minutes. Complex surgery for more severe injuries could take much longer.

Read more information about recovering from hand tendon repair and the complications of hand tendon repair.

If any of the tendons in your hand are damaged, surgery may be possible to repair them and help restore movement in the affected fingers or thumb.

What are tendons?

Tendons are tough cords of tissue that connect muscles to bones. When you contract (tighten) a group of muscles, the attached tendons will pull on certain bones, allowing you to make a wide range of physical movements.

There are two groups of tendons in the hand:

• extensor tendons – which run from the forearm, across the back of your hand to your fingers and thumb, allowing you to straighten your fingers and thumb
• flexor tendons – which run from your forearm, through your wrist and across the palm of your hand, allowing you to bend your fingers

Surgery can often be carried out to repair damage to both these groups of tendons.

When hand tendon repair is carried out

Hand tendon repair is carried out when one or more tendons in your hand rupture or are cut, leading to loss of normal hand movements.

If your extensor tendons are damaged, you will be unable to straighten one or more of your fingers. If your flexor tendons are damaged, you will be unable to bend one or more of your fingers. Tendon damage can also cause pain and inflammation (swelling) in your hand.

In some cases, damage to the extensor tendons can be treated without the need for surgery, using a rigid support called a splint that’s worn around the hand.

Common causes of tendon injuries include:

• Cuts – Cuts across the back or palm of your hand can result in injury to your tendons. 
• Sports injuries – Extensor tendons can rupture when stubbing a finger, such as trying to catch a ball. A flexor tendon can occasionally be pulled off the bone when grabbing an opponent’s jersey, such as in rugby. In activities that involve excessive and strenuous gripping (such as rock climbing), the pulleys holding the flexor tendons can rupture.
• Bites – Animal bites can cause tendon damage. Human teeth can also cause tendon damage, usually when a person punches another person in the teeth, cutting their hand in the process.
• Crushing injuries – Jamming your finger in a door or having your hand crushed in a car accident can divide or rupture a tendon. 
• Rheumatoid arthritis – Rheumatoid arthritis can cause your tendons to become inflamed. In the most severe cases, this can lead to tendons rupturing.

Tendon repair surgery

Tendon repair may involve making an incision in your wrist, hand or finger so the surgeon can locate the ends of the divided tendon and stitch them together.

Extensor tendons are easier to reach, so repairing them is relatively straightforward. Depending on the type of injury, it may be possible to repair extensor tendons in an accident and emergency (A&E) department using a local anaesthetic to numb the affected area.

Repairing flexor tendons is more challenging because the flexor tendon system is more complex. Flexor tendon repair usually needs to be carried out under either general anaesthetic or regional anaesthetic (where the whole arm is numbed) in an operating theatre by an experienced plastic or orthopaedic surgeon who specialises in hand surgery.

Read more about how hand tendon repair is performed.

Recovering from surgery

Both types of tendon surgery require a lengthy period of recovery (rehabilitation) because the repaired tendons will be weak until the ends heal together. Depending on the location of the injury, it can take up to three months for the repaired tendon to regain its previous strength.

Rehabilitation involves protecting your tendons from overuse using a hand splint. You will usually need to wear a hand splint for several weeks after surgery.

You will also need to perform hand exercises regularly during your recovery to prevent the repaired tendons from sticking to nearby tissue, which can prevent you from being able to fully move your hand.

When you can return to work will depend on your job. Light activities can often be resumed after 6-8 weeks and heavy activities and sport after 10-12 weeks.

Read more about recovering from hand tendon repair.

Results

After an extensor tendon repair you should have a working finger or thumb, but may not regain full movement. The outcome is often better when the injury is a clean cut to the tendon rather than one that involves crushing or damage to the bones and joints.

A flexor tendon injury is generally more serious as they are often put under more strain than extensor tendons. After a flexor tendon repair, it is quite common for some fingers not to regain full movement, although the tendon repair will still give a better result than no surgery.

In some cases, complications develop after surgery, such as infection or the repaired tendon snapping or sticking to nearby tissue. If these occur, further treatment may be required.

Read more about the complications of hand tendon repair.

When you will be able to return home after surgery will depend on how badly your hand was damaged.

You may be able to go home on the same day, once you have recovered from any anaesthetic and arrangements have been made for your aftercare.

After the operation

If you have had a general anaesthetic, you will wake up in the recovery room after your operation. You may have an oxygen mask on your face and you may feel a bit drowsy.

If you had a regional or local anaesthetic, you will be able to go back to the ward sooner, but your arm will be numb and floppy for several hours.

It is normal for your hand to be elevated in a sling (a large bandage designed to support a body part) to reduce swelling.

Following the operation, your hand is likely to be bruised and swollen and, when the anaesthetic wears off, it will be painful. You may need to take painkillers, such as ibuprofen, paracetamol or codeine for up to two weeks.

Before you leave hospital, you will be advised about keeping your hand above the level of your heart whenever possible to help reduce swelling. For example, you may be advised to raise your arm on cushions while seated or hold your arm up to your other shoulder while standing and walking.

You will not be able to drive for several weeks after the operation, so you will need to arrange for someone to pick you up and take you home from the hospital. If you live on your own and you have had a general anaesthetic, you may be advised to stay in hospital overnight. You may also need to stay overnight if you need hand therapy in hospital before you go home.

Recovery and rehabilitation

Before you leave hospital, a hand therapist may replace the rigid plaster splint (a support designed to protect the hand) fitted during the operation with a lighter and more flexible plastic one. This splint will help to prevent the repaired tendons from being overstretched.

You will usually be advised to wear the splint at all times for three to six weeks, possibly followed by just wearing it at night for a further couple of weeks.

Your hand therapist will advise you about looking after your splint and what to do if you develop any problems with it. It’s important to avoid getting the splint wet, so covering it with a plastic bag while having a bath or shower will usually be recommended.

You will be taught a number of different hand exercises after the operation, either before you leave hospital or at an appointment a few days later. These exercises are designed to prevent the repaired tendons from getting stuck to surrounding tissue, which would reduce your range of hand movements.

The specific exercises recommended by your hand therapist or surgeon will vary according to the type of tendon repair you had.

If you smoke, it is highly recommended that you stop because smoking can impair the blood circulation in your hand and delay your recovery time. Read more about stopping smoking.

Returning to work and activities

How quickly you can return to work and resume normal daily activities will depend on the nature of your job, as well as the type and location of your injury.

The repaired tendon will usually be back to full strength after about 12 weeks, but it can take up to six months to regain the full range of movement and in some cases you may never be able to move the affected finger or thumb as much as you could before it was damaged.

In general, most people are able to:

• resume light activities, such as using a keyboard or writing with a pen, after 6-8 weeks
• drive a car, motorcycle or heavy goods vehicle (HGV) after 8-10 weeks
• resume medium activities, such as light lifting or shelf stacking, after 8-10 weeks
• resume heavy activities, such as heavy lifting or building work, after 10-12 weeks
• resume sporting activities after 10-12 weeks

Your hand therapist or surgeon can give you a more detailed estimate of your likely recovery time.

It is vital that you follow all the instructions and advice given to you regarding the use of your hands during your recovery period. If you attempt to use the repaired tendons before they have fully healed, it could cause the repair to rupture.