According to the Agency for Healthcare Research and Quality, over 600,000 knee replacement surgeries take place every year in the United States. If you suffer from osteoarthritis, other degenerative disease, or previous musculoskeletal trauma and are considering knee replacement surgery, Thomas F. Calton, MD, can help. Dr. Tom Calton is an orthopedic surgeon and leading specialist in knee replacement, including complex revisions. Using the Stryker Mako Robotic-assist allows Dr. Calton to utilize minimally invasive surgical techniques with precision. Schedule a consultation with Dr. Calton at Elevate Surgical in Ogden, Utah, to discuss options that will improve your life.

My Approach to Knee Replacement: Precision. It’s What I’m Passionate About.

Early in my career, I was frustrated with the lack of precision in knee replacement—with instruments that had a “one size fits all” approach and implants that more less fit the average person, but not those on the periphery. Within a few years of my career beginning, I was busy with hip and knee replacements. I was approached by a small upcoming company and offered a position on their knee replacement design team. I was intrigued. Their initial design had taken the best ideas from two of the leading designs and put them into one. I was presented with an opportunity that not many surgeons ever get, or ever have access to. I accepted the position and got to work. The ideas generated and marinating in my mind throughout years of training and experience were put into action:

  • The last part of a knee replacement is the plastic or polyethylene. Previous to the turn of the century the incremental increase was 2.5mm or 3mm.  This to me was too much. Sort of like having the option of size 6,8,10 or 12 shoes. I needed ½ sizes. My first endeavor was to encourage 1mm size options. No longer would the knee be too tight or too loose…the knee would be just right. 1mm increments were implemented and has now become the standard in the industry today. 
  • Femoral rotation:  When you look at the end of the thigh bone there is an inherent rotation. Early designs provided a 3-degree external rotation for pretty much all knees and there was no precise way to adjust for anatomic variation. I approached Ortho Development and they put their engineers to work. By 2001 we had applied for a patent and by 2009 we received patent number 9449359 for a rotational/adjustable AP block. This tool has allowed precise adjustments for rotation and anterior/posterior adjustment—key elements in placing an artificial knee in precise balance. 
  • Hemi lock:  Standard technique, as of this writing, most knee replacement technique involves checking the knee in two positions: full or near full extension and 90 degrees of bend. A knee requires, however, balance throughout the range of motion. But….there was no way to check. So I designed a way.  I asked our engineers to provide me a heme-block. This block was basically the knee component cut in half. It allows me to check the knee throughout the full range of motion before the final adjustments are made. Circa 2011   
  • Bone Spurs:  Bone spurs on the back of the femur or thigh bone are one of the reasons that arthritic knees lose range of motion. Toward the end of the case a chisel can be used to remove them. However, the limitation of the chisel did not allow for precise contouring of the back of the knee. An osteophyte removal guide was then designed to allow exact bone spur removal or contouring. circa 2014
  • Current design considerations:  My interest in Robotics has widened my view of standard instrumentation. One of the robotic tricks when a knee presents with a unique problem of being tall in the front back dimension is placing a too large of a knee component. The solution in robotics is to flex the knee component and downsize the knee which better accommodates a narrow femur bone. One night not long ago I awoke at 3AM and had an idea. I sketched it on a piece of paper and in the morning, I sent the drawings to our engineers. Within days I had seen the first CAD drawings and I am right now awaiting the prototype blocks to add yet another option to better prepare to replace every single knee with balance and precision.