Pomerene Hospital Blog
A Total Knee Replacement "Just For You"
Knee replacement surgery was first performed in 1968. Originally, joint replacement surgery was reserved for patients typically over 70 years old. Due to concerns of implant failures, replacement surgery on younger patients was avoided. Although these procedures typically improved arthritic knee pain, some residual pain, stiffness and a feeling that the knee was never quite normal was not uncommon. Since then, there have been advancements in surgical materials and techniques which have greatly increased the effectiveness and longevity of the replacement. Knee replacement surgeries are commonly performed at the hospitals of Wayne and Holmes County as well as the Wooster Ambulatory Surgery Center by local orthopaedic surgeons.
Standard off-the-shelf, non-customized knee joint replacement surgery is a safe and effective procedure to relieve pain, correct deformity and help you resume normal activities. Despite this, some patients are still hesitant to consider total knee replacement surgery. When asked why patients with a painful, arthritic knee are postponing surgery, many patients admit to waiting for a "new or better" procedure. Customized knee replacement surgery with patient specific cutting guides and a customized implant may likely be their answer. In simple terms, the implant is the metal and plastic that is used by the surgeon to replace the patient's removed arthritic knee bone.
For the first time in this area, customized knee implants are now available for patients who need partial or total knee replacement surgery. These fully customized knee implants are uniquely designed for each patient and are manufacturing using proprietary, advanced "image to implant" technology developed by ConforMIS. With the use of a standard computerized tomography (CT) scan of the patient's arthritic leg, an individual patient specific total knee replacement or partial knee replacement, with associated custom cutting blocks to be used by the surgeon, can be performed. Using 3-D printing technology, the knee joint is created one thick layer at a time with the same materials used for a traditional non-custom replacement. In essence, they are designing the implant to fit the bone rather than the bone to fit the implant, which better replicates the patient's natural anatomy. This process results in the implant that is the precise size and shape of the patient's individual joint.
This technology may represent a significant advantage over the current off-the-shelf knee implants. Off-the-shelf implants are available in only a limited range of sizes and shapes. As a result, when using off-the-shelf implants, surgeons need to make more extensive cuts to the patient's bone to accommodate the implant. This may be a major factor that causes approximately 1 out of every 5 knee replacement patients to suffer residual pain caused by ill-fitting implants. This also may result in a mismatch between the size and shape of the patient's bone and non-custom implant which may result in functional limitations for the patient. With customized implants, the size and shape of the implant is knee and patient specific, which may lead to a more normal feeling knee with better range of motion and higher patient satisfaction.
During the custom procedure, the surgeon cuts less bone to accommodate the implant, therefore patients can experience less trauma and postoperative pain. Patients with customized implants may have faster recoveries and be more satisfied with the results. The greater preservation of bone also helps to position patients for successful future surgeries if necessary,
Another benefit of customized knee implants is that they are developed with complete single use, customized cutting guides for the orthopaedic surgeon to use only on that patient. Because the implants are single use and disposable, there is reduced sterilization required compared with reusable instruments. There is less potential for contamination compared to reusable instruments. The cutting guides are also manufactured via 3-D printing and calibrated based on the patient's unique CT scan so they can fit the implant with the maximum precision. This allows the orthopaedic surgeon to align the implant more exactly. Proper placement and alignment has been found to help reduce implant wear and help ensure that the prosthesis lasts as long as possible.
While many patients do fine with non-customized knee replacement surgery, it is hoped that customized total knee replacement surgery will increase the number of more satisfied patients, giving them a more normal feeling, long-lasting knee replacement with less postoperative pain and an easier recovery.
If you or a loved one are experiencing arthritic knee pain and have been told you may need a knee replacement, the best way to find out if you are a candidate is to be evaluated by an orthopaedic surgeon. Please call 330.674.0775 for more information or to schedule an appointment.
Blog Written By: Rodney Miller, MD