Robotic Total Knee Replacement Superior to Conventional Approach


Individuals who plan to undergo a total knee replacement may find that the doctors in the operating room have some help from a robot. Surgeons at Mercy Medical Center in New York have found that use of computer-assisted robotics for this procedure provides results superior to those associated with conventional techniques.

Approximately 478,000 total knee replacements are performed in the United States every year. About 70 percent of these procedures are performed on people older than 65. Serious complications occur in less than 2 percent of patients, according to the American Academy of Orthopaedic Surgeons (AAOS) , and about 90 percent of patients are satisfied with the results.

In the Mercy Medical Center study, surgeons evaluated the results of 1,000 consecutive computer-assisted robotic total knee replacements conducted over five years. They discovered that the procedure achieved leg alignment within three degrees in 100 percent of the robotic procedures, compared with only 50 to 80 percent of the time using conventional surgery.


The robotic approach also resulted in no early failures and no need for revision surgical procedures following a misalignment, instability or loosening of the replacement over the five years of the study. This compared with conventional total knee replacement surgeries which are associated with a 3 to 8 percent failure rate per year, with 50 percent of early knee replacement failures associated with misalignment, instability, and loosening.

Computer-assisted robotic knee replacement surgery resulted in a final post-surgical leg alignment that averaged less than one degree. This benefit is in addition to the lack of the need for a second surgical procedure, known as a revision total knee replacement, which typically is more difficult and less successful than the original procedure.

Knee replacements are most often performed because of knee osteoarthritis. The AAOS reports that knee osteoarthritis is a leading cause of disability in the United States, and that approximately 9 million adults were diagnosed with the condition in 2005. As the population ages, the need for more knee replacements will likely rise. Therefore, the finding that robotic knee replacement is superior to the conventional approach is good news for potential patients.

American Academy of Orthopaedic Surgeons
Mercy Medical Center