Custom Knee Replacement
This procedure restores function to a severely damaged knee. Most commonly, it is used to repair a knee that has been damaged by arthritis. During the procedure, the surgeon replaces the damaged portions of the knee with artificial parts. These parts consist of a metal femoral component, a metal tibial component and a plastic spacer. A small plastic patellar component may also be used.
Total knee arthroplasty (replacement) procedures have been vastly improved by new advances in technology. A custom-fit total knee arthroplasty offers patients an implant that has been tailored to the exact specifications of personal anatomy. Each device is comprised of replacement components for the ends of the tibia and femur bones as well as a spacer that rests in the middle. Rather than using standard implants, the custom-fit system replaces the worn joint with implants that are sized, shaped and contoured according to the patient's unique structure.
Creation of a Custom-Fit Implant
In order to develop a truly customized implant, 3-D image of the patient's knee must be created prior to the knee replacement surgery. An MRI scan is taken of the affected knee, producing images that provide extensive information about the tissues and bones of the joint. All of this data is entered into an advanced computer program that formulates a detailed 3-D image to be used to tailor the implant and surgery to the particular patient.
Based on the computer-generated 3-D image of the knee, the damaged areas are corrected virtually. This enables a customized implant to be designed, taking into consideration the precise measurements and angles necessary for the individual patient. It is specific to the anatomy of the patient's arthritic knee and takes into consideration the exact location in which device will be implanted.
Advantages of a Custom-Fit Implant
The custom-fit total knee replacement procedure offers a number of benefits over traditional methods. The precision of the customization allows:
- More consistently successful surgical outcomes
- Less wear and tear on the implant over time
- Shorter surgery
- Shorter recovery period
- Less pain after surgery
- Greater preservation of healthy tissue
- Greater postsurgical stability and function
In addition, patients with custom-fit appliances report that the knee feels more natural than do patients who have had traditional devices implanted.
The Custom-Fit Arthroplasty Procedure
After general anesthesia has been administered, the surgeon makes an incision in the knee. Using the information provided by the computer model as a guide, the surgeon cuts the bone in predetermined, highly specific locations. The exact placement of the surgical cuts helps ensure that the knee will have optimal alignment and stability as well as the ability to rotate normally.
A trial implant may initially be placed within the joint in order to test for fit and alignment. Once the surgeon determines the most accurate positioning and balance within the joint, the custom-fit implant itself is inserted and fixed in place with cement. The surgeon then closes the incision.
Recovery from Custom-Fit Arthroplasty
A custom-fit total knee arthroplasty generally requires a hospital stay of 2 to 4 days. Mobility is encouraged almost immediately following the surgery. Most patients have to use assistive devices, such as crutches, canes or walkers for several weeks to ensure that the knee does not bear too much weight while it heals.
Physical therapy is very beneficial after a custom-fit total knee replacement surgery. The length of rehabilitation varies, but a course of 6 to 12 weeks is usually recommended. The therapy focuses on restoring strength, flexibility and full range of motion to the affected knee. Patients are usually advised to continue assigned physical therapy at home. Complete recovery is typically achieved within 3 to 6 months after the procedure.