Computer Navigation in Hip Replacement
By Louay Toma, M.D.
Some of the latest technology in joint replacement includes not only implant material advances, but also advances in how we place the components during the reconstructive surgery. As other articles on this site discuss, there are different surgical approaches in hip replacement that can make significant differences in early and late outcomes. Another technology that is attempting to improve early and late outcomes by making implant placement more accurate is computer aided surgery or CAS.
Currently all primary hip and knee replacements in my practice are being done utilizing computer guidance for implant placement. I’ve used this technology since August 2006 for hip replacement. Nearly all patients are candidates for CAS except the very morbidly obese. The technology itself has been available in limited markets for a few years and mainly in knee replacement. Recent software developments have expanded the technology to hip replacement, however.
[info_box]The goals for CAS are simple; to improve implant placement, ligament balance and leg length control in an effort to customize each joint replacement with the patient’s anatomy, thereby minimizing implantation related complications. In hip replacement the potential complications of interest are angular malalignment, dislocation, and leg length discrepancy.[/info_box]
Thus far CAS has been very successful in achieving the above goals. In the hip, leg length prediction is very precise decreasing my need for x-ray during the case and avoiding any surprises post operatively.
It is important to understand that CAS is not robotic surgery. The surgeon obtains highly accurate information from the computer, but the surgeon ultimately has complete control and must apply the information correctly. The information obtained is highly precise but could be inaccurate if input information into the computer is incorrect.
There are very few downsides using CAS. Four additional 5mm wounds are made to place pins in the pelvis. There has been very little pain from these wounds reported by patients In my experience, there have only been improvements using CAS. No reconstructions have been adversely affected in my hands with this technology. Again, CAS is an additional tool not the only tool used to properly reconstruct hips.
At this point I have no reason to return to non-navigated replacements. Both in the knee and the hip CAS is another check in an effort to make every joint replacement as close to perfect as possible. Individual patient considerations at times force certain limitations in replacement surgery, but with proper pre-operative planning and additional intra-operative information from technologies such as CAS, surprises during and after surgery can be minimized.
For general information regarding hip replacement surgery or further details regarding the minimal anterior approach contact our office.