By Henry Clayton Thomason, III, M.D.
As the population grows older, arthritis will affect hundreds of thousands of people and more and more will go to their doctor to see what, if anything, can be done to alleviate the pain. There are numerous conservative, non-operative treatments available from nutritional supplements like glucosamine and chondroitin sulfates to anti-inflammatory drugs like naproxen to cortisone and hyaluronate injections. But for some people the pain continues and surgery becomes the treatment of choice. Knee replacements, both partial and total, have improved in many ways in the last five to ten years from newer techniques to improved implants to better pain management to a quicker rehabilitation process. All of these modifications offer hope for the population to get back to a happier, pain free lifestyle.
Modern technology has improved the knee replacement in many ways. The traditional cobalt chrome metal used for years has been improved with titanium alloys and even some ceramic models. The old polyethylene, or plastic, inserts have also been improved to become stronger and last longer. Some designs have rotating components to allow more motion and less wear or breakdown of the plastic. We now have implants that replace only a portion of the knee if the arthritis has only worn out part of the joint. All of these improvements mean that in the average sixty-five year old patient, the chance that the knee replacement will last twenty years is over ninety percent. Not long ago people were hoping for ten to fifteen years before the implant wore out and the surgery needed to be revised.
Surgeons have developed better techniques for knee replacement surgery as well. Smaller incisions with less dissection and cutting of the deeper tissues allow quicker recovery and less pain. The partial knee replacement is also done through improved techniques. In some hospitals surgeons have begun to use computer assisted techniques to optimize implant position and alignment to prevent long term wear of the components. This means that the replacements may last even longer.
There have also been many changes in the anesthesia used and the post-surgery pain management. Many patients are candidates for and now receive spinal or epidural anesthetics for their surgery. Most knee replacements can be done in less than two hours which allows this type of anesthesia to be used. This means that the patient is less likely to get nauseated and sick afterwards and can participate in rehab sooner. Regional anesthetics like these have also been proven to reduce the chance of blood clots. In the days following surgery, intravenous morphine and other narcotics were traditionally used. Now, longer acting oral medications control the pain better and are not as sedating.
Many hospitals like Gaston Memorial Hospital have instituted dedicated “joint camps” or programs that streamline the entire process to make it more efficient and successful for patients. Patients take classes before the surgery to get oriented to the procedure and then go through the physical therapy afterwards in groups. Group therapy provides an improved level of comfort for the patients and the camaraderie helps encourage people through the process. There are also dedicated nurses on the orthopaedic floors for patients with joint replacements. Patients are up out of bed often the same day of surgery and walking. Most patients are able to leave the hospital in just three days. Many are able to walk comfortably and even start driving within just a few weeks.
All of these improvements do not mean that total knee replacements are small or trivial operations or that they should be taken lightly. Many people still get great relief with conservative, non-operative treatments and do well for years without surgery. Joint replacement should be for only those that have tried and failed to get adequate relief from other modalities. Younger patients may want to proceed with a total knee replacement prematurely to get rid of the pain. However, we still have a long way to go before the implants are expected to last for thirty or forty years.
Total knee replacements can and do improve the lifestyle of patients immensely. There is a wealth of information available to people now in the literature and through the internet about all of these new improvements and modifications. However, not all of it is proven yet and should not be taken for granted. The academy of orthopaedic surgeons has a website (orthoinfo.aaos.org) that is very informative to the public and non-biased to specific implants and companies and can provide answers to many questions. Not everyone is a candidate for every prosthesis or technique as a patient’s overall health, weight, mechanical alignment, or history of prior surgeries on the knee may affect the procedure and the ultimate outcome. Overall, patients should feel better about the results of the modern total knee replacement but should consult their doctor or orthopaedic surgeon if the pain of arthritis is affecting their activities and they are considering surgery.
Dr. Clay Thomason is an Orthopaedic surgeon with Carolina Orthopaedic & Sports Medicine Center, P.A. in Gastonia, NC. He is on staff at Gaston Memorial Hospital. For more information, please visit our website at www.CarolinaOrthopaedic.com.