Knee Arthroscopy

Knee arthroscopy is a surgical procedure performed using a small camera, called an arthroscope, inserted into the knee joint to diagnose and treat a wide range of knee problems.The camera displays pictures on a video monitor, and these images are used to guide miniature surgical instruments. As the arthroscope and surgical instruments are thin, only very small incisions are required, rather than the larger incision needed for open surgery. This results in less pain for patients, less joint stiffness, and often shortens the time it takes to recover and return to favorite activities. The majority of patients are discharged from the hospital on the same day.

Anatomy

The knee is the largest and one of the most complex joints in the body. The bones that make up the knee include the lower end of the femur (thighbone), the upper end of the tibia (shinbone), and the patella (kneecap). The patella glides in a groove (trochlea) in the distal anterior femur. The smaller bone of the lower leg (fibula) forms a joint with the shinbone.

Other important structures that make up the knee joint include:

Articular cartilage - The ends of the femur and tibia, and the undersurface of the patella are covered with articular cartilage. This slippery substance helps your knee bones glide smoothly across each other during movement
Synovium - The knee joint is surrounded by a thin lining called synovium, which releases a fluid that lubricates the cartilage and reduces friction during movement.
Meniscus - Two C-shaped pieces of meniscal cartilage act as "shock absorbers" between your femur and tibia. The meniscus is tough and rubbery to help cushion and stabilize the joint as well as increasing the conformity of the ends of the bones.
Ligaments – The bones ones are connected to each other by ligaments. The four main ligaments in your knee act like strong ropes to hold the bones together and provide stability.
The two collateral ligaments are found on either side of your knee.
The two cruciate ligaments are found inside your knee joint. They cross each other to form an "X" with the anterior cruciate ligament in front and the posterior cruciate ligament behind.
Muscles – These are attached via tendons to the bones and provide mobility to the knee.

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Indications for Knee Arthroscopy

Knee arthroscopy may be recommended if you have a painful condition that does not respond to nonsurgical treatment. Nonsurgical treatment includes rest, physical therapy, and medications or injections that can reduce inflammation.

Common arthroscopic procedures for the knee include:

Removal or repair of a torn meniscus
Reconstruction of a torn cruciate ligament (most commonly the anterior cruciate)
Removal of inflamed synovial tissue
Trimming of damaged articular cartilage
Removal of loose fragments of bone or cartilage
Treatment of patella (kneecap) problems, in particular patellar maltracking/malalignment
Certain fractures involving the knee
Treatment of knee sepsis (infection)
Management of a Baker’s cyst (a fluid filled cyst that develops at the back of the knee due to the accumulation of synovial fluid, and often occurs with knee conditions such as meniscal tear, knee arthritis and inflammatory conditions.

Surgical Procedure

Knee arthroscopy is usually performed under general anaesthesia, but can be performed under local or regional anaesthesia.

To begin the procedure, two or three small incisions, called "portals", are made in the knee. A sterile solution will be used to fill the knee joint and rinse away any cloudy fluid as well as to push apart the various internal knee structures, providing a clear view.

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An arthroscope, which is a narrow metal tube with a small camera on the end is inserted, and the image is projected onto a video monitor screen. The internal knee structures are examined to assess the cause of the knee problem. If surgical treatment is needed based on the diagnosed problem, tiny instruments are manipulated through other small incisions. Specialized instruments are used for tasks like shaving, cutting, grasping, and meniscal repair. In many cases, special devices are used to anchor stitches into bone. Most knee arthroscopy procedures last less than an hour. The length of the surgery will depend upon the findings and the treatment necessary. The saline is then drained from the knee joint, and each incision is closed with sutures, and then the knee is covered with a sterile dressing and a soft compression bandage.

After the Surgery

After surgery, you will be moved to the recovery room and should be able to go home within 1 or 2 hours. Be sure to have someone with you to drive you home and check on you that first evening. While recovery from knee arthroscopy is faster than recovery from traditional open knee surgery, it is important to follow instructions carefully after you return home:

The small incisions generally heal without much of a scar; the stitches are removed after 10-14 days at your postoperative appointment. Patients are advised to leave waterproof dressings on the wounds until this time. The knee can be washed but should be dried thoroughly.
You will be given specific pain killers and/or anti-inflammatory medication which the discharge nurse will go over with you before you leave the hospital
If you are discharged home the same day following a surgical procedure in the Day Surgery Unit, you will usually be contacted within 24 hours by a nurse educator to access your progress and to answer any queries you may have.
Full weight bearing after surgery is acceptable provided that you are comfortable. Crutches can sometimes be required, but please ask the hospital staff or physiotherapist for the correct instructions on their use before you leave.
You can remove the bandage but leave the wound dressing intact after 48 hours. You can shower and wet the operated area but be sure to dry thoroughly. Apply tubigrip mid-thigh to lower calf to assist with any swelling.
Patients should try to do at least 200 straight leg raise exercises per day for the first week after surgery.
It is possible to return to work the day following surgery, however it is recommended that you rest and elevate the leg with ice for 5 days. Should you need a medical certificate please ask the rooms and this can be provided.

Complications

The complication rate after arthroscopic surgery is very low. If complications occur, they are usually minor and are treated easily. Possible postoperative problems with knee arthroscopy include:

Infection
Blood clots (DVT)
Knee stiffness
Accumulation of blood in the knee
Continuing knee problems
Compartment syndrome.