Knee scope, Arthroscopic lateral retinacular release; Knee arthroscopy; Patellar debridement
Knee arthroscopy is a surgery in which a small camera is attached to a video monitor and is used to examine or repair tissues inside the knee joint with special instruments.
Arthroscopic surgery on the knee involves inserting a small camera (less than 1/4 inch diameter) into the knee joint through a small incision (barely larger than the camera). This camera is attached to a video monitor which the surgeon uses to see inside the knee. In some facilities, the patient can choose to watch the surgery on the monitor as well.
For a simple surgical procedure, a local or regional anesthetic is administered, which numbs the affected area, but the patient remains awake and able to respond. For more extensive surgery, general anesthesia may be used. In this case the patient is unconscious and pain-free.
After the camera is inserted, saline is pumped in under pressure to expand the joint and to help control bleeding. Some surgeons also use a tourniquet to prevent bleeding.
After looking around the entire knee for problem areas, the surgeon will usually make 1-4 additional small incisions to insert other instruments. Commonly used instruments include a blunt hook to pull on various tissues, a shaver to remove damaged or unwanted soft tissues, and a burr to remove bone. A heat probe may also be used to remove inflammation (synovitis) in the joint.
At the completion of the surgery, the saline is drained from the knee, the incisions closed, and a dressing applied. Many surgeons take pictures of the procedure from the video monitor to allow the patient to see what was done.
Arthroscopy may be recommended for knee problems, such as:
- A torn meniscus (either repair or remove)
- Mild arthritis
- Loose bodies (small pieces of broken cartillage) in the knee joint
- A torn or damaged anterior cruciate or posterior cruciate ligament
- Inflamed or damaged lining of the joint (synovium)
- Malalignment of the knee cap (patella)
The risks for any anesthesia are:
- Allergic reactions to medications
- Problems breathing
The risks for any surgery are:
Additional risks include:
- Bleeding into the joint (hemarthrosis)
- Damage to the cartilage, meniscus, or ligaments in the knee
- Failure of the surgery to relieve symptoms
- Knee stiffness
Expectations after surgery
Use of arthroscopy has reduced the need to surgically open the knee joint. This has resulted in less pain and stiffness, fewer complications, decreased length (if any) of hospitalization, and faster recovery time. Expectations vary widely with the indication for the surgery.
Surgery done for a meniscal tear or loose bodies when the patient has no other problems (like arthritis) is usually uncomplicated, and most patients can expect a full recovery. The presence of arthritis dramatically reduces the effectiveness of arthroscopy and up to 50% of patients may not improve post-operatively.
Arthroscopic removal of the synovium (arthroscopic synovectomy) can be of great benefit to patients with rheumatoid arthritis. Arthroscopic or arthroscopic-assisted surgery done to repair the meniscus or reconstruct ligaments in the knee is much more complicated with prolonged recovery and more variable results.
For a simple meniscal cleaning (debridement), recovery is usually quite rapid. The patient may need to use crutches for a while to reduce weight placed on the knee joint to control pain. Pain can be managed with medications.
For more complicated procedures where anything is fixed or reconstructed, patients may not be able to walk on the knee for several weeks, and the overall recovery may be anywhere from several months to a year.
by Potos A. Aagen, M.D.