Patient Information Sheet
It has been recommended that you undergo an arthroscopy of your knee. This information sheet is designed to explain what is involved in an arthroscopy, the reasons why you may require one and what to expect on the day of surgery and after.
The Anatomy of the Knee Joint
What is an arthroscopy?
‘Arthro’ means joint and ‘scope’ is to look at. Therefore a knee arthroscopy allows the surgeon to view inside your knee and directly inspect the bone and structures within. This gives a much more accurate picture than any other investigation such as x-ray or MRI.
Arthroscopy is commonly known as ‘keyhole surgery’ as the incisions are minimal and therefore reduce scarring and allow quicker recovery. Prior to the advent of the arthroscope, such operations would mean a full open operation with extensive scarring etc.
During an arthroscopy a small camera-type device is inserted into the knee and this relays pictures to a television screen. At the same time instruments can be inserted into the knee so that surgery can be performed e.g. removing a portion of meniscus (“cartilage”).
Reasons for arthroscopy
There are many reasons for an arthroscopy. Listed below are the most common reasons.
1. Meniscus (Cartilage) Tears
These tears can happen with a sudden twisting movement and even by repeated squatting. Your knee may swell and it may also catch or lock when you move it. The meniscus will need to be resected (trimmed) or repaired. The menisci are 2 semi – circular structures of soft fibrocartilage which act as shock absorbers within the joint. If you have a tear in the meniscus the torn section is resected - ‘trimmed’ back to healthy stable meniscus. Occasionally it is possible in some circumstances to repair the torn cartilage, although this is most common in the young adult or child.
2. Anterior Cruciate Ligament Tears (ACL Tears)
The cruciate ligaments are 2 strong ligaments, the anterior and the posterior, which provide stability to the knee on twisting and pivoting activities. The ACL Ligament can be torn by falling, a twist and even a blow. Often injured in contact sports and skiing. These tears cause pain, swelling and an unstable knee. Arthroscopy allows a clear view and physical inspection of the cruciate ligaments. The cruciate ligaments do not have the ability to repair themselves and it may be necessary to operate at a later date to reconstruct them. In a reconstruction, the damaged tissue is replaced with healthy, strong tissue.
3. Often through trauma or degenerative changes (osteoarthritis) small fragments of bone or articular cartilage can become loose within the knee joint. These can be removed and ‘washed out’ of the joint.
4. The smooth articular cartilage lining of the bone which allows smooth movement can be damaged when the knee is injured. This may result in a ‘divot’ of cartilage becoming loose and causing pain and locking of the joint. Via an arthroscopy the extent of the damage can be assessed and procedures carried out. The lesion can be shaved or a procedure known as micro – fracture performed where small ‘pricks’ are made in the bone to stimulate healing from the deeper levels. If the lesion is too large for this, further surgery can be planned from the arthroscopy findings.
5. If the joint lining is particularly inflamed then a small area of this lining (biopsy) can be taken and sent for further investigations as to the cause.
6. The kneecap (patella) can be a source of pain in the knee. The arthroscope allows inspection of the under surface of the patella. If there is any loose articular cartilage this can be shaved. Another procedure called a ‘lateral release’ can be performed. This is the surgical division of the soft tissues on the outer aspect of the patella. These structures can be extremely tight causing the patella to track in the wrong position. This tightness over a long time can place excess pressure on the under surface of the patella resulting in pain.
These are the most common reasons to have an arthroscopy. There are other reasons and your Consultant will explain these to you if necessary.
Please take the time to shave the front half of your knee from the middle of your thigh to the middle of your shin prior to your admission. This makes the admission process easier and quicker and helps you and the staff. Please take care though not to cut yourself!
A knee arthroscopy is almost always performed under a general anaesthetic. This can normally be done as a day case procedure, although on some occasions you may be advised to remain in hospital on the night of the surgery.
In most arthroscopies, three small incisions are made at the front of the knee. One incision is to insert the arthroscope, the other to insert the instruments required during the procedure and the third to attach a tube that inflates the knee with fluid. In some cases additional incisions are necessary.
Most arthroscopies take between 30 – 60 minutes to perform. At the end of the operation, the fluid is drained from the knee. Stitches are not usually required to close the wounds; Local anaesthetic is injected into the knee to minimize discomfort after surgery. A white stocking and padding are applied to the leg. Adequate information on what to do with the dressings, padding and stockings will be given to you on the day of your surgery.
With modern anaesthetic techniques, most patients usually wake relatively quickly and are aware of their surroundings within one hour of the end of the procedure.
What can you expect after your arthroscopy?
You will only have to spend a short time in the recovery room and will only have a few incisions to look after. Pain and scarring are limited.
Unless advised to the contrary, you may place weight upon your knee immediately after surgery (although on the first time please do this under the supervision of a nurse or physiotherapist). You may go home once you are safely walking and you do not normally require crutches. As a general anaesthetic has been given, you must not drive for 48 hours after surgery, and should not be alone for about a 24 hour period. The nurses on the ward will advise you further on this if necessary.
It is normal for the knee to feel a little uncomfortable on the day after your operation. This is because the local anaesthetic inserted into the knee at the end of the operation may have started to wear off. Pain-relieving tablets may be required for a few days. These will be given to you on discharge from hospital. You will also be given some anti inflammatory tablets to reduce swelling and, indirectly, pain unless there are any contra-indications to these.
You may consider driving again after approximately 3-4 days. However, do NOT drive unless you are happy that you are safe. It may be in your interests to inform your motoring insurance company that you are resuming driving after your operation.
You will normally be seen in the out-patient clinic at 1 week after surgery. At this appointment, your surgeon or his nursing assistant will look at your knee to check the status of the wound healing, function and your general status. If a video or cd is recorded at the operation, this will be given to you. Please bring it back so it can be used to explain the operation. Some surgeons usually suggest that physiotherapy commences at about 1-2 weeks, but your surgeon will discuss this with you on the day of your surgery.
You will be told how much activity the knee can tolerate after surgery. This varies from patient to patient, but in most cases strenuous activity should be avoided for one month. If activity is resumed too early, the knee can swell somewhat and be painful.
It is vital to realize that although arthroscopy is ‘key hole surgery”, it is still a significant procedure. It is normal for the knee to swell for 2-3 months after the operation and for the knee to feel a little unstable until the muscles are fully developed again. You may experience an ache at the front of the knee at the site of the incisions for 2-3 months.
An arthroscopy is only recommended if it is thought that it will improve your symptoms and may help plan further surgery. However, it may not be possible for all your symptoms to improve, especially in degenerative (“wear and tear”) conditions.
What can go wrong after an arthroscopy?
There is no surgical procedure in existence that is without possible complications! Arthroscopy can result in a number of complications. However, these are infrequent and the procedure is one of the safest operations in Orthopaedic Surgery.
- Bleeding after the operation.
- Swelling of the knee – some swelling is inevitable after the operation.
- Venous thrombosis (“clots in the veins”). Every attempt is made to minimise this complication. TED stockings (white long stockings) are used on both legs which compress the calf muscles and prevent DVT. Anti-inflammatory medications also play a role in thinning the blood slightly and contributing to prevention of DVT. We mobilize patients very quickly after surgery thus reducing the risk further. The risk of DVT after arthroscopic surgery is extremely low.
- Infection – a rare but serious complication.
- Following a lateral release of the patella it is quite common to be bruised on the outer aspect of the thigh and calf as soft tissue and muscle is cut.
IT IS RECOMMENDED THAT YOU DO NOT UNDERTAKE ANY AIR TRAVEL FOR 4 WEEKS AFTER YOUR SURGERY. PLEASE DISCUSS ANY TRAVEL PLANS WITH YOUR SURGEON PRIOR TO YOUR SURGERY.