Knee

As the knee is comprised of 3 separate compartments, the typical x-ray involves 3 views to look at each compartment critically. Once non-operative measures have been implemented and failed, discussions of joint replacement become the logical next step. The goals of knee replacement are to restore function, improve range of motion, provide a fluid and smooth surface for mobility and decrease pain.

Knee replacement involves the measured resection of the remaining irregular cartilage surface down to the level of the subchondral bone. This is similar to removing the peel from an apple. Meticulous care is taken to realign the normal joint to its pre-arthritis condition. Instruments known as “jigs” are used to assist in this realignment. New technology involves the use of an MRI pre-operatively to create custom blocks and improve the accuracy of the alignment process. Your surgeon will address this with you, specifically assessing the benefits for your individual case. This process is called Visionaire and may help in decreasing the possibility of malposition of the components (the most common complication following knee replacement surgery). Once the bone has been prepared, the surgeon will choose a replacement style that best reproduces the kinematics of a normal knee. Multiple styles are available. Often choices are made based on a long effective track record with these implants. New models which may offer theoretical significant benefits may not be chosen until their successes are confirmed. Discussions regarding the choosing of company and model are always welcomed during your planning visits. Once chosen, this sizing is confirmed and adjusted accordingly intraoperatively for the best fit. The implants are then opened and affixed to the bone surfaces. There are two ways to apply the implants, cementation versus porous. In the cemented type, the implant is glued to the bone. This is in contrast to the porous type which requires the bone to adhere to the undersurface of the implant without any adhesive material. If either of these methods fail, the implant will loosen and a revision will be necessary. This is the second most likely complication of knee replacement surgery.

Following surgery, early and aggressive rehabilitation (physical therapy) is critical for maximum success. The knee capsule which was opened to perform the procedure will tend to scar and tighten resulting in stiffness of the knee joint postoperatively. Early motion is critical to preventing this complication. New anesthesia and postoperative pain techniques have become helpful in achieving early safe mobility. Hospital stays range between 1 and 3 days based on the completion of therapy goals. There is clearly a transition towards discharge home versus inpatient rehabilitation centers. Physical therapy will persist for approximately 12 weeks following surgery advancing in difficulty until all goals are met. Swelling and warmth of the joint, a measure of the inflammation, may persist up to 6 months post-surgery. This is normal and the way in which our bodies heal. During the postoperative period, there will be several scheduled visits at your surgeon’s office to evaluate your knee and your progression. X-rays will be obtained during your 8 week visit to confirm maintenance of the proper placement.

It is important to work hard on your range of motion after surgery. For some it can take 3-6 months to maximize your motion. The amount of motion that you get after knee replacement is dependent on several factors including how much motion you had prior to surgery. It is important to work closely with your physical therapist and your surgeon to ensure that you are meeting all of your range of motion goals.

The term revision encompasses many possible procedures, from single liner exchange to complete removal of all existing parts. The recovery difficulty is related to the type of revision procedure. However, revisions are usually more difficult, requiring more surgical time and, thus, more swelling and pain post-operatively. Ultimately, although slightly more difficult at the start, most revisions follow similar recovery timelines and are significantly improved three to six months post-operatively.

Yes. Due to needing to remove hardware (prior implants), there is increased risk of bone loss. With less bone available, the risks of subsequent fracture and loosening are also increased. Exposure is more difficult, and scar tissue formation may be increased. Finally, additional procedures increase the risk of subsequent infections.

Revision implants do look similar to primary components but with the addition of “stems” and “cones.” Stems are used to bypass weak and previously utilized regions of the femur and tibia bone. They are used to gain contact with normal bone further up and down. They are essential to adequate fixation of the new parts to host bone. Cones are a recent advancement in reconstructive surgery and allow the ability to fill bone deficits with metallic support structures allowing for bone on-growth. This combination of normal bone healing increases the likelihood of long term success.

When the arthritis (wear) is isolated to a single region.

No, there are several differences, but the overall outcome or success is similar.

The largest difference is the size of the implants. Because the surgery is isolated to a single compartment, the incision size is smaller, as is the surgical procedure. This results in a shorter procedure and quicker recovery. In addition, the center ligaments (ACL/ PCL) are maintained, and, thus, stability of the knee is improved.

No, the three options are markedly different. For medial or inside arthritis, there are two standard options. These are determined by whether the polyethylene insert is mobile or fixed. One is not better than the other, and the decision can be made after evaluation and discussion with your surgeon. For lateral, or outside, arthritis, there is only one option. Finally, the patellofemoral replacement involves resurfacing both the femur and the patella, and again only one option is available.

Inserting the camera through a small incision allows Dr. Bowling to see inside the knee without having to make a large incision. Many times, he is able to repair the problem using addition pencil thin instruments through another small incision. Some examples of conditions that may be repaired or corrected with arthroscopy include damaged or torn cartilage, ligament tears, infections, or loose bone fragments. The most common condition that requires a knee arthroscopy is a meniscus tear. The meniscus is a tough spongy tissue between the femur and tibia that act as shock absorbers on the knee. There are two type of meniscus tears, traumatic and degenerative. A traumatic tear is usually the result of an injury such as a twist or fall. A degenerative tear is more common in an older population. The meniscus can wear thin over time and become more prone to tear with less trauma.

As with any surgical procedure, there is a risk of infection. Placing the instruments and moving the instruments inside the joint can cause damage to the cartilage. Any procedure that last for more than an hour can place a patient a risk of developing a blood clot.

• You will not be able to drive yourself home from the hospital after anesthesia, so plan ahead to have a friend or family member be available drive you home and to take care of you after surgery. You will likely need help for the first few days to a week afterward. • Do not eat or drink anything after midnight the day before your surgery. This includes black coffee, tea or water. • Wear comfortable loose clothing to the surgery. This will make changing back into your clothes after the surgery less painful.