Dallas County Living Well Magazine Summer 2014

The Perfect Fit—Customizing Your Knee Replacement Surgery By Dr. Richard G. Buch P eople living with advanced knee arthritis often experience severe pain when climbing stairs, exercising or even just walking. Medication, physical therapy, and injections are commonly prescribed to treat the pain associated with arthritis, but these options often provide only short term or partial relief. For many patients a knee replacement is the only option left. There are only two different types of knee implants available: “off-the-shelf” standard implants that are premade or customized implants that are produced individually to fit a specific patient. Standard implants are the most commonly advertised knee replacements. Understanding the differences between these options can help patients better prepare for a discussion with your physician about knee implant surgery. Off-the-shelf implants Off-the-shelf knee implants are manufactured by the majority of companies, and were for many years the only 36 North Dallas Living Well Magazine • Summer 2014 type of implant available. Most off-the-shelf knee implants are manufactured in a range of sizes––usually with six or seven size options. Because every knee has a unique size and shape, surgeons have to take steps to try to fit off-theshelf knee implants to a patient’s knee. To do this, surgeons must surgically remove more of the patient’s healthy bone and tissue. Even with these steps, surgeons are often unable to align an off-the-shelf implant precisely for a perfect fit. In many cases, the implants are slightly wider or narrower than the patient’s surrounding bone. Even minor differences in fit can affect knee function and studies show this occurs in 20-25% of patients, causing pain, stiffness, swelling, and loss of motion. Customized implants In recent years, a company called ConforMIS introduced customized knee implants. Each implant is developed based on a CT scan of the patient’s own knee. The scan is first used to develop a full 3D map of the knee. Using 3D printing, ConforMIS then produces a precise wax implant mold. This mold is then used to form the metal components of

Dallas County Living Well Magazine Summer 2014 | Page 38