Correct alignment of the component and soft tissue balancing have been cited as two of the most important aspects of successful knee replacement (arthroplasty). They are the most important predictors of longevity of knee replacement. Minor misalignment can lead to early loosening, early polyethylene wear and poor function.
Knees have traditionally been aligned using jigs either loosely clamped on to the outside of the leg or referenced from rods placed in the middle of the bones. The majority of knee replacements (prosthesis) can be implanted in a satisfactory position using this older technology. However, a proportion of components may be mal-aligned, potentially leading to poorer function and earlier failure.
Computer navigation in total knee replacement attempts to correct some of the problems faced in traditional total knee replacement.
Dr. (Prof.) Anil Arora and his team are among a very exclusive group of surgeons who have advanced training in computer navigation surgery and utilise this technique in the operating room.
The objective of computer-assisted surgery is to combine the precision and accuracy of computer technology with the surgeons’ skill and expertise. As a result, Dr. Arora and his team are able to achieve alignment of implants with a degree of accuracy not possible with the naked eye. This surgical procedure affords their patients enhanced results and recovery along with a quick return to normal life.
A computer-assisted knee replacement procedure begins with the Dr. Arora placing several small arrays on the patient’s leg. An infrared camera is used to track the movement of the arrays via a computer that analyzes the positions and creates an anatomical three dimensional drawing of the knee. Using this real-time graphic display, Dr. Arora makes cuts in the bone to ensure proper alignment on the mechanical axis for the implant. The implant is then secured with bone cement, tested to ensure proper alignment, and the incision is closed with stitches.
At the completion of total knee replacement surgery, balancing the ligaments surrounding the knee has always been the most difficult and "subjective" part of knee replacement surgery. In conventional surgery the knee ligaments are balanced chiefly by the surgeons "feel" to determine if the ligaments are appropriately taut. Though experienced surgeons can achieve excellent ligament balance in most cases, reproducibility is difficult and results are subjective. With computer navigation, ligament balancing can potentially be quantified to the nearest millimeter of ligament laxity or tautness.
Dr. Arora has been using use this exciting technology for his knee replacements for the last several years. He has now accumulated a wealth of experience using this technique and has been involved in training other surgeons wishing to use the technology.
For a brief demo of the procedure, visit Computer Assisted Knee Replacement
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