Ever wonder what osteoarthritis is? In order to understand the reason I perform total joint surgery, I think it is helpful to understand the nature of the disease. When you understand what is going on, the procedure makes more sense.
Osteoarthritis is a Joint Surface Problem
Osteoarthritis is the wearing out of the joint. All of the joints in our bodies have cartilage that cover the bone. This joint surface cartilage, also known as articular cartilage, is critical for the joint to work properly. When the cartilage is normal, the joint works without any problems.
I often compare this cartilage to the tread on the tires of your car. In the same way that the tread can wear down and thin over time, so can the articular cartilage. The wear is sometimes minimal and you may not even notice any problems with the joint. Sometimes, however, the wear is severe. In some patients the cartilage wears all the way down to the bone. In this case, instead of having a joint surface with cartilage against cartilage, the joint is bone against bone. This is the most severe form of osteoarthritis.
Sadly, currently there is no way to put cartilage back in an arthritic joint to make it like it used to be.
What Does This Look Like on an X-ray?
X-rays of the joint primarily just show the bone. The cartilage is not visible at all. When you look at a normal X-ray of a joint, there is a “space” between the two sides. This “space” isn’t a real space at all. It is actually the cartilage.
As you can imagine, when the cartilage starts to wear out, the joint space starts to thin. In severe forms of osteoarthritis, bone on bone osteoarthritis, the joint space will be completely gone.
Many people also develop bone spurs or osteophytes at the sides of the joint surface. The osteophytes are a result of the chronic inflammation in the joint. While the osteophytes look bad, they are rarely a cause of pain. They are more an indication of what is going on inside the joint and help make the diagnosis.
How do You Treat Osteoarthritis?
Since we are unable to put cartilage back in the joint, treatments surrounding osteoarthritis focus on decreasing inflammation. As you can imagine, a bad joint surface can create high levels of chronic inflammation. Many patients start with a nonsteroidal anti-inflammatory (NSAID) medicine such as ibuprofen (often known as Advil) or naproxen (often know as Aleve). There are other NSAID’s that are available as prescription only.
Some patients will try other noninvasive treatments such as physical therapy and bracing. For some people this will provide relief, but for many they do not help as much.
The next step in treatment is often a cortisone injection. Cortisone is a combination of a numbing medicine, such as lidocaine, and a steroid. The steroid is injected directly into the joint and can have a strong anti-inflammatory effect.
With steroid injections there are two important questions to ask. How well does it work? How long does it last? How long the injection lasts is very difficult to predict. In some people it can provide relief for months and months. In others it only lasts a few weeks. A common response would be around 3 months. Cortisone injections can cause the osteoarthritis to get worse faster, so there is a limit to how often the injections can be performed.
How Does Joint Replacement Surgery Fix the Problem?
Joint replacement surgery, whether it is a knee or a hip, give the patient a new joint surface. In knees I basically resurface the joint, cutting off about 8mm of bone to replace with metal on both the femur and tibia sides. I then put a plastic liner between the new metal surface of the femur and the tibia. The new joint surface is metal and plastic.
In hip replacement surgery I cut below the ball of the hip and remove it. I insert a metal stem into the femur which has a metal neck that I can put a ceramic ball on to. On the socket side, I insert a metal socket and then insert a plastic liner. The new hip joint surface is ceramic and plastic.
When Should Patients Consider Joint Replacement Surgery?
There are multiple factors in deciding when to consider joint replacement surgery. It is important that the diagnosis be correct. Some issues that can cause joint pain overlap with osteoarthritis. For example, hip pain sometimes is actually caused by a pinched nerve in the low back.
It is also important for the patient to try conservative measures before proceeding with surgery. In medicine, we are always weighing the risks and benefits of treatment. If an NSAID or a cortisone injection can keep you going, in general there are fewer risks to these treatments and are often preferred. Taking on the risks of surgery begin to make sense once these simpler treatments no longer work.
The third, and perhaps most important, consideration is how the pain affects you. I always ask my patients what their pain keeps them from doing. For some people it is exercise or sports such as tennis or golf. For other patients it is shopping. For many it is traveling or working in the garden. If you find yourself giving up on the things you love to do because of arthritis pain, I would highly encourage you to have a conversation with a surgeon about joint replacement options.
The right time to do a surgery is when you have exhausted the other treatments and the pain from the osteoarthritis keeps you from being yourself.
