Computer Navigation

Figure 1. Light-emitting diodes are attached to the bones of the leg and knee and are used to communicate to a computer.

As osteoarthritis progresses, the knee becomes more misaligned, stiff, and deformed. Restoring alignment is critical for the long-term success of a knee replacement. Precise position of the implants is another critically important element of the durable knee replacement.

Figure 2. Computer Navigation Machine: Monitors every step of the surgery and allows error to be identified and corrected.

Most knee replacements done today are done using alignment jigs and cutting blocks. These are relatively simple devices that rely on the surgeon’s ability to see and feel when the knee is properly alignment and balanced. Research has demonstrated that experienced surgeons using these traditional methods have limited success in properly balancing and aligning knee replacements.

Figure 3. Real-time digital reconstructions of the knee and leg allow the surgeon to confirm every step of the surgery.

Computer navigation is a recent advancement in joint replacement surgery. Light-emitting diodes (Figure 1) are attached to the leg. These devices communicate directly with a camera attached to a computer (Figure 2) and allow the surgeon to create digital reproduction of the entire surgery (Figure 3).

Component position, range of motion, ligament tensioning, and overall limb alignment are accurately and clearly viewed at every step during the operation. Errors in techniques that would otherwise go unnoticed can be quickly seen and corrected. Computer navigation used during knee replacement helps to minimize the amount of surgical dissection and to ensure proper positioning of the implants.

Computer navigation in knee replacement

Tremendous advances have been made in joint replacement that makes it a viable option for a greater number of people than ever before. Over the past four decades joint replacement has been proven to relieve severe joint pain and restored joint function in over 90% of patients undergoing the procedure.¹²

Accurate alignment of the knee components is critical to the overall function of your new joint, ^9,10 and it also plays a role in helping your joint feel healthy again, and helping the joint replacement to potentially last longer. Computer-assisted technology has made it possible to navigate joint replacement procedures with a level of accuracy so precise it may improve the results of your surgery.⁶

Benefits of MIS-Navigation Knee Replacement

Potential advantages of Computer Navigation:

Provides comprehensive data about anatomy, alignment, and component position which may result in more exact placement of your joint replacement
Allows the surgeon to more accurately plan for your surgery with the use of digital images of your hip, knee and ankle⁷
Provides the surgeon with more control, feedback and the ability to correct potential errors during the surgery⁶
Allows for better visualization of anatomy with less need for exposure, which is particularly important when minimally-invasive techniques are used

There are several potential benefits for those who have computer-assisted surgery with their total joint replacement, including:

May increase the life of your replacement¹
Reduces the risk of dislocation and revision surgery⁶
Results in greater stability and range of motion ^3,8,9
Helps improve the overall function of your joint replacement ^5,9

Computer-assisted surgery may allow for less-invasive surgical techniques, which have several other potential advantages, including:

Reduced blood loss during surgery, which lessens the need for a blood transfusion ^5,8
Faster recovery ^3,5,7
Reduced length of your hospital stay ^5,11
Shorter post-operative physical rehabilitation ^5,12
Less scarring^10,12

¹ McAllister, CM. The Role of Unicompartmental Knee Arthroplasty Versus Total Knee Arthroplasty in Providing Maximal Performance and Satisfaction. The Journal of Knee Surgery. Vol 21. Number 4. October 2008.
² McAllister, CM and Stepanian JS. The Impact of Minimally Invasive Surgical Techniques on Early Range of Motion After Primary Total Knee Arthroplasty. The Journal of Arthroplasty, Volume 23, Issue 1, Pages 10 - 1.
³ McAllister, CM and Stepanian, JS. High-Performance Alternatives to Total Seminars in Arthroplasty, Volume 17, Issue 2, Pages 31-92 (June 2006).
⁴ McAllister, CM, Stepanian, JS. High Performance Alternatives to Total Knee Arthroplasty. Seminars in Arthroplasty June 2006 (Vol. 17, Issue 2, Pages 72-79).
⁵ McAllister, C.M., Stepanian J.D. Minimally Invasive Total Knee Replacement: The Impact of Everting the Extensor Mechanism on Early Range of Motion. Orthopedics Today. July, 2005.
⁶ Sikorski JM, Chauhan S. Computer- Assisted Orthopaedic Surgery: Do we need CAOS? J Bone Joint Surg 2003; 85-B:319-23.
⁷ Noble PC, Sugano N, Johnston JD, Thompson MT, Conditt MA, Engh CA Sr, Mathis KB. Computer Simulation: How can it help the surgeon optimize implant position? CORR. 2003 Dec; (417):242-52. ⁸ Widmer KH, Grutzner PA. Joint replacement-total hip replacement with CT-based navigation. Injury. 2004 Jun; 35 Suppl. 1:S-A84-9.
⁹ Klein GR, Parvizi J, Venkat RR, Mathew AS, HozackWJ. Evaluation of in vivo knee kinematics by a computerized navigation system during total knee arthroplasty. J Arthroplasty. 2004 Dec; Vol. 19:986-91.
¹⁰ Keggi, Kristaps. Total hip arthroplasty through a minimally invasive anterior surgical approach, JBJS, Vol. 85-A.
¹¹ Tria AJ, Minimal Incision Total Knee Arthroplasty, CORR 2003, Vol 416.
¹² Zanasi, Stefano. Minimally Invasive Computer-assisted Total Knee Arthroplasty through a Subvastus Approach, October 2006. Article from: Orthosupersite.com.
¹³ Kalairajah, et al. Blood Loss after total knee replacement, JBJS, Vol. 87-B, No. 11, Nov. 2005.