Knee replacement surgery advanced by computer technique

For patients, minimally invasive surgery means significantly less scarring, less soft tissue disruption, less pain and much speedier recovery times — benefits that cannot be overstated

By: Lorraine Seabrook
   Did you know that more than 300,000 Americans (a number that is expected to increase as the population ages) undergo knee replacement surgery each year, making the knee the most frequently replaced joint in the body? Because the knee is assigned to the body’s heavy work detail, it is at high risk for injury and disability caused by damage to cartilage from rheumatoid arthritis, osteoarthritis or trauma.
   Knee replacement surgery is generally recommended for patients with severe knee pain and disability. This type of surgery is highly successful in relieving pain and restoring the function and use of the knee.
   Not long ago, however, total knee replacement surgery was largely reserved for people at least 60 years old. Long-lasting materials, improved mobile-bearing design and advanced techniques now allow surgeons to replace total and partial knees on younger people. Mobile bearing designs in partial and total knee replacement, where the polyethylene insert can pivot as well as flex and extend, are becoming increasingly popular. They have increased conformity of the plastic, which acts to spread out the load and minimize the wear that can cause early failure.
   Patients contemplating knee replacement surgery will be thrilled to learn that an incredibly advanced computer-assisted technique is now available, enabling surgeons to decrease the size of a patient’s incision without sacrificing precision. For patients, minimally invasive surgery means significantly less scarring, less soft tissue disruption, less pain and much speedier recovery times — benefits that cannot be overstated.
   How does this technology work? Consider how the Global Positioning System (GPS), the worldwide radio-navigation system that uses 24 man-made satellites and their ground stations to calculate accurate positions anywhere on earth, has made life easier for hikers, sailors, even local drivers, by giving every square meter on the planet its own address.
   Now imagine a GPS for human anatomy, which uses markers and infrared signals picked up by a computer with two cameras attached, and you will understand the excitement generated by the Ci System, developed by Brainlab and customized for Johnson & Johnson/DePuy implants. This totally integrated, customizable, computer-assisted package offers surgeons the ability to make informed decisions and exercise more control over the surgery at every stage of the procedure.
   According to Harvey E. Smires, M.D., board-certified orthopaedic surgeon at University Medical Center at Princeton, "This system allows me to verify everything I’m doing on a step-by-step basis, giving me confirmation of the choices I’m making, from tibia cuts to implant size. The computer navigation is accurate to fractions of a millimeter and fractions of a degree of alignment. I am able to anticipate the outcome before the surgery is complete and make the best possible decisions during surgery."
   Using its integrated components (software, hardware and instruments), the Ci System provides real-time, three-dimensional images of the individual patient’s anatomy that are easily visible regardless of the size of the incision. As a result, surgeons using the system have a clear view of the bone structure and detailed information to assist with alignment of the implants during surgery.
   In addition, surgeons are able to customize joint replacement procedures by defining individual patient anatomy with unique technology that morphs the patient’s bone directly onto the computer screen. This happens without the use of X-rays during surgery.
   Dr. Smires, who has performed countless joint replacement surgeries, used this new system in early July when he performed a bilateral total knee replacement surgery on a 61-year-old patient who was suffering from osteoarthritis. The surgery was a complete success and both surgeon and patient knew this immediately.
   The patient, Robert Cirigliano of Monroe Township, explains, "I’ve been eager to undergo the procedure performed with the Ci System ever since Dr. Smires told me about it. I felt extremely reassured prior to my surgery knowing Dr. Smires had technology at his fingertips that would help him customize the surgery and implant to my own knee. Of course, like all patients, I had my fears about surgery and my doubts about being able to attain the quality of life I had before I began experiencing knee problems. I’m happy to say that my doubts, along with my pain, have been erased. The ability to resume my normal daily routine without debilitating knee pain is amazing."
   Dr. Smires admits that patient fear associated with surgery is quite common. "It’s unfortunate that people would rather live in pain than pursue surgery. It’s my hope that with the benefits I see with the Ci System — better accuracy and precision — as well as patient success stories, people will choose quality of life over living with pain."
   The surgeon is quick to point out that, as with any surgery, there are risks, and this procedure is not appropriate for everyone. Recovery takes time and hard work, and each patient responds differently. The life of a new joint depends on weight, activity level, age and other factors.
   If you are experiencing pain, and treatments such as pain medication, injection therapy or arthroscopic surgery fail to provide pain relief, explore the possibility of this advanced surgery with your physician.