Arthroscopy - knee

How knee arthroscopy is carried out

About knee arthroscopy

Knee arthroscopy is a procedure used to investigate and diagnose knee problems such as inflammation or injury. You can also have a knee problem treated during arthroscopy, for example, damaged tissue and cartilage can be repaired or removed. It’s also used to take small tissue samples (biopsies), which can help to diagnose problems such as infection.

Knee arthroscopy is performed through small cuts in your skin. Your surgeon will use a special telescope (arthroscope) attached to a video camera and small surgical instruments to do the procedure. You should recover from arthroscopy more quickly than if you have open surgery.

What are the alternatives?

Not everyone who has a knee problem needs to have arthroscopy. Your doctor may diagnose your knee problem by examining your knee or from an X-ray or an MRI scan. An MRI scan uses magnets and radio waves to produce images of the inside of your body. Some knee problems, such as injuries can be treated using physiotherapy and medicines.

Preparing for a knee arthroscopy

Your surgeon will explain how to prepare for your operation. For example if you smoke you will be asked to stop, as smoking increases your risk of getting a chest and wound infection, which can slow your recovery.

The operation is usually done as a day case, which means you will have the procedure and go home on the same day.

You may have arthroscopy under general anaesthesia or local anaesthesia. If you have a general anaesthetic you will be asleep during the procedure. A local anaesthetic completely blocks pain from your knee and you will stay awake during the operation. Your surgeon may offer you a sedative with a local or regional anaesthetic, which relieves anxiety and helps you to relax during the operation.

If you're having general anaesthesia, you will be asked to follow fasting instructions. This means not eating or drinking, typically for about six hours beforehand. However, it’s important to follow your anaesthetist’s advice.

At the hospital your nurse may check your heart rate and blood pressure, and test your urine.

Your surgeon will discuss with you what will happen before, during and after your procedure, and any pain you might have. This is your opportunity to understand what will happen, and you can help yourself by preparing questions to ask about the risks, benefits and any alternatives to the procedure. This will help you to be informed, so you can give your consent for the procedure to go ahead, which you may be asked to do by signing a consent form.

You may be asked to wear a compression stocking on the unaffected leg to help prevent blood clots forming in the veins in your legs. You may need to have an injection of an anticlotting medicine called heparin as well as, or instead of, wearing compression stockings.

What happens during a knee arthroscopy

Arthroscopy can take from 30 minutes to over an hour, depending on how much work your surgeon needs to do inside your knee joint.

Once the anaesthetic has taken effect, your surgeon will make small cuts in the skin around your knee joint. He or she will put sterile fluid into your knee joint to rinse out any cloudy fluid. This helps your surgeon to see the inside of your knee clearly. Once the arthroscope has been inserted, your surgeon will examine your knee joint by looking at images sent to a monitor. He or she can insert instruments, such as scissors or lasers, to repair or remove damaged tissue, such as cartilage or ligaments.

Afterwards, your surgeon will drain the fluid out and close the cuts with stitches or adhesive strips. Then he or she will wrap a dressing and a bandage around your knee.

What to expect afterwards

You will need to rest until the effects of the anaesthetic have passed. It may take several hours before the feeling comes back into your knee. Take special care not to bump or knock the area.

You may need pain relief to help with any discomfort as the anaesthetic wears off.

You will usually be able to go home when you feel ready. However, you will need to arrange for someone to drive you home. You should try to have a friend or relative stay with you for the first 24 hours.

Your nurse will give you some advice about caring for your healing wounds before you go home. You may be given a date for a follow-up appointment.

The length of time your dissolvable stitches will take to disappear depends on what type you have. Non-dissolvable stitches are usually removed 10 to 14 days after surgery.

Recovering from knee arthroscopy

If you need pain relief, you can take over-the-counter painkillers such as paracetamol or ibuprofen. Always read the patient information that comes with your medicine and if you have any questions, ask your pharmacist for advice.

General anaesthesia temporarily affects your co-ordination and reasoning skills, so you must not drive, drink alcohol, operate machinery or sign legal documents for 24 hours afterwards. If you're in any doubt about driving, contact your motor insurer so that you're aware of their recommendations, and always follow your surgeon’s advice.

You may be asked to wear compression stockings on your unaffected leg to help maintain circulation.

You will have a dressing over your knee joint when you leave the hospital. Keep your knee and the dressings clean and dry. Your surgeon or nurse will tell you when you can have a bath or shower.

Continue with the exercises your physiotherapist has given you, as they will help to improve your knee movement and strength.

You may not be able to put weight on the leg that has been operated on, so you may not be able to stand or walk without help. Crutches or a walking frame may be available to help you. Your surgeon or nurse will give you advice on how to use these and for how long.

Your knee joint is likely to feel sore and swollen. Try to keep your leg raised on a chair or footstool when you're resting. You can apply a cold compress such as ice or a bag of frozen peas, wrapped in a towel, to help reduce swelling and bruising. Don’t apply ice directly to your skin as it can damage your skin.

Follow your surgeon's advice about driving. You shouldn't drive until you're confident that you could perform an emergency stop without discomfort. This is usually about one to three weeks after your operation.

Your recovery time will depend on the type of treatment, if any, your surgeon performs on your knee joint. You should be back to your usual activities six to eight weeks after your operation, depending on how severe your knee problems were. Some people may be able to return to their usual activities sooner than this. If you do heavy physical work as part of your job, you may need a longer time before you can return to work.

What are the risks?

As with every procedure, there are some risks associated with knee arthroscopy. We have not included the chance of these happening as they are specific to you and differ for every person. Ask your surgeon to explain how these risks apply to you.


These are the unwanted, but mostly temporary effects you may get after having the procedure.
You may have some pain and swelling around your knee after the procedure. You will also have small scars on your knee from the cuts.


This is when problems occur during or after the operation. The possible complications of any operation include an unexpected reaction to the anaesthetic, a wound infection, excessive bleeding or developing a blood clot, usually in a vein in the leg (deep vein thrombosis).
Arthroscopy complications can include:

  • accidental damage to the inside of your joint
  • infection inside your knee joint, called septic arthritis
  • damage to your nerves, which can lead to loss of feeling in the skin over your knee
  • bleeding into your knee joint

What can I do to make my recovery easier?


Try to be as fit and healthy as possible before your operation and prepare your home for when you return.


If you're having knee arthroscopy, it's a good idea to try to be as fit and healthy as possible before your operation to speed up your recovery.

You should stop smoking as smoking can increase the chances of getting an infection and slows your recovery. If you're overweight your doctor may recommend a weight loss programme to follow before your operation.

You can also exercise to strengthen your upper body. This will help you to get around after the surgery when using walking aids such as crutches.

If possible you should try to strengthen your leg muscles. Strengthening the muscles around your knee will speed your recovery and will make it easier to perform the exercises you will be given after your operation. Your surgeon or physiotherapist will be able to recommend exercises for you.

It's a good idea to prepare your home for when you return from hospital. This may involve rearranging furniture to make it easier to move around when you’re using crutches and placing commonly used items where you can reach them easily. It's also a good idea to stock up on non-perishable food such as frozen or tinned items, so that you don't need to go shopping immediately after your surgery.

You may need someone to help during the first few days at home.

When can I start exercising again and what exercises are suitable?


After your arthroscopy you should exercise regularly to restore your knee's movement and strength. Don't do any high-impact exercises, such as running, until you're fully recovered.


You will need to gradually rebuild the strength and movement in your knee following arthroscopy.

Your surgeon may recommend specific exercises for your knee which you can do at home. These exercises involve stretching and tightening muscles and bending and flexing your knee. You may also have physiotherapy for several weeks after your operation.

To begin with you will need to take it very easy. You will need to do exercises at home for about two weeks and then you should be able to start gentle exercise such as walking. Always stop if your knee swells or if you feel any pain. If this happens you should follow the PRICE procedure:

  • Protect your knee from further harm.
  • Rest your knee for two to three days, then re-introduce movement so you don't lose too much muscle strength.
  • Ice the injured area using an ice pack or ice wrapped in a towel to reduce swelling and bruising. Don’t apply ice directly to your skin as it can damage your skin.
  • Compress the area by bandaging it to support your knee and help reduce swelling. The bandage should fit snugly but not be too tight, and you should remove it before going to sleep.
  • Elevate your knee to control swelling. Keep the area supported and try to keep it elevated as much as possible until the swelling goes down.

You should be able to return to your usual levels of activity after six to eight weeks but you shouldn't do any high-impact exercises, such as running, or exercises that involve twisting, such as skiing, until you have made a complete recovery.

Your surgeon or physiotherapist will be able to give you more information about what activities are suitable for you.

Will my knee recover completely?


Your knee may not recover completely after your operation. Your recovery will depend on the damage to your knee and how severe it is.


A knee arthroscopy can be used to treat a variety of knee conditions but your recovery will depend on the amount of damage to your knee. Your surgeon may not know how severe your injuries are until you have your arthroscopy and your surgeon has a good view of the inside of your knee. You may have injured your knee in such a way that prevents it from recovering completely.

If the injury or damage to your knee is severe, you may need to change your lifestyle to adapt. This may mean changing the activities and exercises you do.

Do the exercises recommended by your surgeon or physiotherapist so that you recover as much fitness as possible. Don’t do any high-impact exercises, such as running, or exercises that involve twisting, such as skiing, until you have made a complete recovery.