Surgical Treatment of Osteoarthritis of the Knee

The first line of treatment for osteoarthritis of the knee is always conservative nonsurgical treatment. However, if conservative treatment does not relieve pain and improve function, your physician may recommend surgery. The choice of treatment should be a joint decision between you and your physician.

The purpose of surgical treatment for osteoarthritis of the knee is to reduce pain, increase function, and improve overall symptoms. Patient satisfaction is a fundamental goal in treating osteoarthritis of the knee. Surgical treatment options include arthroscopy, osteotomy, and arthroplasty.


Arthroscopy is a surgical procedure that uses small incisions and miniature instruments. A tiny telescope, called an arthroscope, is inserted into the joint space, which is then filled with fluids so the surgeon can clearly see the components of the joint. This enables the surgeon to look directly at the bone surfaces and determine how advanced your arthritis is.

Using the miniature arthroscopic instruments, the surgeon can trim damaged cartilage, remove loose particles or debris from the joint (débridement), and clean the joint (lavage or irrigation). If other problems are discovered, such as a torn meniscus (a C-shaped piece of cartilage that cushions the knee) or a damaged ligament, the surgeon can correct them during the same surgery.

Arthroscopy can be helpful if your joint pain results from a tear in the cartilage or meniscus, or if bits of debris are causing problems with bending or straightening the joint.

In people younger than 55 years, arthroscopic surgery may help delay the need for more serious surgery, such as a joint replacement.

As with any surgery, there are some risks with arthroscopy due to the use of anesthesia and the possibility of infection. Other complications include damage to nerves or blood vessels, the development of blood clots in veins, and scarring.

Arthroscopy is not the best option for everyone. Although the incisions are small and pain is minimal, it takes several weeks for the joint to recover fully. Your physician will prescribe a specific activity and rehabilitation program to encourage recovery and protect future function of the joint.


An osteotomy may be recommended if damage to your knee cartilage is primarily in one section (compartment) of the knee. The inside (medial) compartment, where the inner knob of the thighbone (femoral condyle) meets the top of the shinbone (tibia), is most commonly involved.

An osteotomy may also be recommended if a broken knee does not heal properly. This procedure involves reshaping the bones to improve knee alignment. The surgeon repositions the joint to move the mechanical axis of weight bearing for the limb away from the damaged area. This shifts the stresses of weight bearing from the damaged section to a healthier part of the knee.

An osteotomy can restore knee function and diminish osteoarthritis pain. It may even stimulate the growth of new cartilage. Although an osteotomy can decrease pain and improve function, the results often deteriorate over the long term. Many people who have an osteotomy will eventually need a total knee replacement (arthroplasty).

As with all surgeries, there is a slight possibility of infection, complications from the anesthesia, or other surgical complications, such as blood clots, nerve damage, and circulation problems. There will be a cosmetic difference between the surgically treated knee and the untreated knee.


An arthroplasty is a joint replacement procedure. If your knee pain is severe and significantly limits your movement, your physician may recommend that the diseased bone and tissue be replaced by an artificial joint.

If your arthritis is localized to one side of the knee, an orthopaedic surgeon may recommend a unicompartmental knee arthroplasty. If both sides of the knee are affected, a total joint replacement may be more appropriate. The replacement parts are made of cobalt-chrome or titanium metals and smooth, wear-resistant plastic (polyethylene).

The results of total joint replacement are generally excellent. Patients experience significant pain relief and improved physical functioning. There are some risks to the surgery, and full rehabilitation may take 3 to 6 months. In addition, the prosthesis (artificial joint) may eventually loosen or wear out so that a second surgery is needed. However, at the 10-year mark, the success rate with most prostheses today is about 90%.

Your orthopaedic surgeon should discuss the type of knee replacement, the type of surgery (minimal incision or standard incision), the potential risks, and the rehabilitation protocol with you before you make your decision.

This information is based on the Improving Musculoskeletal Care in America project of the Council on Research, Evidence-based Practice Committee, and Department of Research and Scientific Affairs, American Academy of Orthopaedic Surgeons.

The material presented is for educational purposes only and is not intended to present the only, or necessarily best, method or procedure for the medical situations discussed.