The vast majority of patients reading this book with an interest in knee surgery will be considering either total or partial knee replacement. However, there are some other surgical alternatives that exist for arthritis. Most of these options were developed in the years before joint replacement or resurfacing was widely available, but some are still performed today in select cases.
One notable exception is knee arthroscopy, which is a versatile procedure with many applications that involve looking inside the knee. For that reason, it is discussed in its own chapter.
Knee Fusion (Arthrodesis)
In the years before knee replacement, a common surgery for a severely arthritic knee was to fuse the femur to the tibia, usually with a long rod through the center of the bones, effectively eliminating the joint and creating a single bone from the thigh to the ankle.
This surgery persisted even after the development of knee replacements, primarily as an option for young patients (such as laborers) who would otherwise wear out an artificial joint very quickly. Modern designs and materials have largely made this surgery obsolete, however, and it is very rarely considered as a first (primary) surgery for arthritis in this country. Few patients today in America would be willing to accept the limitations of a fused knee. It is problematic with sitting at a movie theater or on an airplane, and even getting in and out of a car can be difficult.
The principal disadvantage of a fusion is that there is no longer any motion at the knee, given that the bones are fused together. This leads to an awkward gait pattern. Sitting and walking are severely affected. Also, the back and the hip typically begin to develop arthritis from "double duty" trying to accommodate the lost motion.
However, once the two bones have fully grown together, a fusion will rarely need any further medical treatment. There is no implant to wear out, break, or become infected. It is also much cheaper than using a knee replacement prosthesis. For this reason, this surgery is still used in poorer parts of the world where knee replacement is not an option for patients. In this country, it is primarily used today as a salvage option after failed or infected joint replacement surgery.
Osteotomy
An osteotomy involves cutting the bone and realigning it to heal in a different position or angle. You could think of it as a controlled, surgical fracture. Several types of osteotomies have been used over the last century for the treatment of arthritis and other knee problems. Note that osteotomies are used for different bones in the body for treatment of a variety of problems.
One particular application that is still used for early knee arthritis is a high tibial osteotomy, which involves cutting the upper end of the tibia and re-aligning it in such a way as to take weight off of the worn out side and to increase weightbearing on the "good" side of the knee. This changes the angle of the leg. Therefore, to be considered a candidate for the surgery, most patients need to have severe arthritis in only one side of the knee with preservation of the joint on the other side. It is most often considered for a young patient with heavy physical demands, such as a heavy laborer, who traditionally has been a difficult to treat candidate for replacement surgery because of the demands placed upon the knee.
Most osteotomies take a long time (months) to heal. Studies have also shown increased incidence of complications when the osteotomy is later converted to a knee replacement, making that eventual surgery significantly more complex and riskier. Increasingly, many orthopaedic surgeons and the orthopaedic literature in general are considering partial and total knee replacements with modern materials and designs to be a better option than osteotomy, but there are still many advocates of its use, and for certain patients with specific needs it may still be an attractive option.
Interpositional Devices
When one side of the knee joint wears out and the leg becomes bowed, some surgeons have tried inserting various interpositional devices into the knee to "shim" it back to normal alignment. Essentially, this involves making a small incision and inserting a small disk-like device (typically metal) into the worn out side of the knee. This was initially tried many years ago and abandoned by most surgeons in favor of partial or total knee replacement, although periodically newer designs resurface with renewed interest.
While the various "spacer" devices often do work in correcting alignment, they typically have not been very effective with pain relief. Most orthopaedic surgeons recommend partial or total knee replacements as a more proven technology.
At the time of this writing, there is some renewed interest in this type of surgery with custom-made inserts. Several companies are offering smooth metal spacers that are custom made based on 3D CT scan or MRI data for individual patients. Once the custom made spacer is manufactured, it is inserted in a very short (possibly outpatient) procedure through a small incision and using an arthroscope. While it is an attractive concept, there is not much experience or data on these new devices yet.
Knee Arthroscopy
Knee arthroscopy involves looking inside the knee with a small camera. Frequently in this type of surgery instruments are used via small incisions, typically less than a quarter of an inch, to remove debris or loose bodies, trim torn cartilage, smooth rough cartilage, and perform a variety of other tasks without a large incision. An entire chapter in this book is devoted to this category of surgical procedures.
While there has been widespread use of arthroscopy to "clean out" arthritic changes from the knee, many joint replacement specialists find that it is best used for accomplishing specific tasks, such as finding a loose body that is causing locking or buckling. While arthroscopy is a great tool for meniscal tears, loose bodies, and other problems, it has a limited role for arthritis treatment.
I explain to my patients that arthroscopy does not "cure" arthritis, and at best it may temporarily improve their discomfort and symptoms for a while, but the best use for outpatient arthroscopy with an arthritic knee is to fix a mechanical problem such as locking. It can also be used to smooth out some isolated areas of roughened cartilage (e.g., chondroplasty), but it does not cure or reverse generalized arthritis. It also can often be used to inspect and photograph the inside of a knee joint to decide whether a patient is a good candidate for a partial versus total knee replacement.
Please remember the information on this site is for educational purposes only and should not be used to make a decision on a condition or a procedure. All decisions should be made in conjunction with your surgeon and your primary care provider.
