As we discussed in our last blog about total hip replacement, there are several factors that influence the outcome of knee replacement. These include surgical technique, fixation of implants, avoidance of wear of the bearing surface, and with regard to motion, the amount of motion that is present prior to knee replacement. Arthritis of the knee is associated with loss of range of motion and when it is significant this loss of motion can impair normal daily walking, getting out of a chair, going up and down stairs, and most recreational activities. Over the last two years, there has been quite a bit of discussion around “high-flex knees”. These are knee replacements designed to allow greater range of motion. In laboratory testing, these types of knees do allow more motion when placed in ideal situations and in patients who have a good range of motion prior to surgery. What is unclear is how significant the difference in range of motion of current total knee replacements and “high-flex knees” are under less than ideal situations or in large groups of patients. In addition to the implant, important surgical factors influence range of motion, including alignment of the limb, placement of the components in proper orientation with regard to rotation and position and the diligence of the patient with their postoperative rehabilitation. All influence range of motion. Talk to your orthopedic surgeon about the various options for treatment of arthritis in the knee.
William P. Barrett, M.D.