Patient-Specific Total Knee Replacement

Total Knee Arthroplasty can sound scary.  

The truth is, the total knee replacement that we know today (aka total knee arthroplasty) is a relatively new accomplishment in the world of medicine.  The Total Condylar Knee, which was the first knee replacement system to completely replace all of the joint surfaces of the human knee, was only developed in 1974 (John Insall, MD, Hospital for Special Services, New York, NY).  This is the system that all subsequent total knee replacements were based on, including the ones that we use today.  So it's only been since the 1970s that we've learned all we know about successfully reproducing total knee replacement.

Dr. Insall's total condylar knee called for replacement of the end of the femur (thigh bone), the tibia (shin bone) and the patella (the kneecap).  He used a special bone cement to hold the components in place, and that's still how most knee systems are put in today.  Its secure, and its proven.  

 
A SUCCESS STORY, STILL BEING WRITTEN.

Given that knee replacement is so relatively new, knee replacement as a specialty continues to evolve and make improvements.  Some specialists are working with knee replacement systems that allow for a patient's bone to grow into the replacement components so that the specialized bone cement is no longer needed.  But so far, the results with these implants haven't proven any better than the tried and true method developed by Dr. Insall.  

Other interesting changes have taken place since those early days of total knee replacement, with surgeons continually focused on trying to improve the experience of the patient as well as the durability of the implant.  Some examples included gender-specific knee replacement in hopes to achieve better results with components that were designed specifically for women because of the inherent differences in their anatomy (these didn't show any difference), variations in surgical technique (also no difference in outcomes) and even robotic knee replacement (also no significant difference in patient outcomes compared to knee replacement by a talented surgeon).

Traditionally, the surgical tools used to make the specific preparations to the bone were the same, regardless of which implant manufacturer's components might be used to replace the knee joint surfaces.  And these tools are still used successfully by many highly skilled and knowledgeable orthopedic surgeons today.  They require drilling holes in the bone, and using metal guides inserted into the bone to provide angles necessary for the cuts to remove the painful joint surfaces ravaged by arthritis.  These guides, while largely dependable, still introduce the possibility of variation on the part of the surgeon.  That variability can play a significant role in the outcome of a total knee replacement.  

Variability is something to be eliminated when it comes to the exacting precision of a joint replacement.  The minimization of variability can be considered key to improving the experiences of patients who undergo total knee replacement.  For this reason, our surgeons use advanced computer-based programs to create a detailed plan for knee joint replacement, using the most contemporary components, specifically tailored for the unique anatomy of each and every individual total knee replacement patient.  

HOW PATIENT-SPECIFIC KNEE REPLACEMENT WORKS

Each patient with painful arthritis of the knee requiring a total knee replacement is first sent for an MRI (magnetic resonance imaging) of their knee, which provides unique data entered into our specialized computers.   Using these computers, changes in not only size, but angle, alignment, and position can all be adjusted and optimized before a patient ever sees the inside of an operating room!  Once the surgeon is satisfied with the plan and component selection, this data is then used to create the physical patient-specific cutting guides, which are uniquely created from the map of a patient's individual anatomy.  

These patient-specific cutting guides are then sterilized and packaged for the sterile environment of the operating room.  These guides will accompany the patient on the day of their surgery into the operating room to help the surgeon recreate the very best knee replacement possible for the individual patient.

A very tall, or muscular person will necessarily have different anatomical variations of their knee compared to the anatomy of a very petite person.  Significant changes are also apparent in the degree to which a specific person's knee is affected by their arthritis.  The patient-specific cutting guides are created taking all of these factors into consideration.  These patient-specific cutting guides serve a critical role in the surgeon's skilled hands, helping him to create surfaces on the bone that reproduce, as closely as possible, a patient's own knee with new, replacement components.  

An added benefit of the patient-specific cutting guides is that they eliminate the need for drilling large holes in the ends of bone to insert guide rods for alignment; holes which can result in additional bleeding.  This means that bleeding is less than that experienced with traditional instrumentation.  This can lead to fewer problems after surgery, and better outcomes.

OUR FOCUS IS ON YOU

With patient-specific cutting guides, our highly skilled surgeons can create and carry out a well-thought out plan for replacement of your knee joint specific to your anatomy.  One size fits no one.  Your knee is as unique and individual as you are.  And we'd like to make sure it stays that way.  

Call us at 972-235-5633 (972-235-KNEE) in order to learn more about how our total knee replacement specialists can help you.