Knee replacements are preformed through an incision on the front of the knee. There are some different ways to handle the soft tissue and extensor mechanism of the knee which are discussed below. Each approach has advantages and disadvantages.
Knee Replacement Approach Types
Medial Parapatellar Approach
A medial parapatellar incision involves cutting the quadriceps tendon above the knee cap (patella) and around the inside (medial) of the knee cap. The tendon is then repaired at the end of the procedure. The idea behind cutting the tendon is that the tendon might heal better than cutting into the muscle belly of the VMO. The patella is typically flipped during this approach to gain access to the knee joint which may or may not affect the knee rehab in the short term.
Mid-Vastus Approach
A mid-vastus approach does not cut the quadriceps tendon but instead cuts into the VMO muscle belly and around the inside of the knee cap. The idea behind leaving a large portion of the VMO attached to the quadriceps is that the VMO muscle may help patellar tracking and knee extension strength. The muscle belly is repaired at the end of the procedure. The patella may or may not be flipped during this approach.
Sub-Vastus Approach
The sub-vastus approach elevates the VMO muscle instead of cutting into it. The incision then extends around the inside of the knee cap. The patella is typically not flipped with this approach. This approach is difficult in muscular patients with large VMO muscles and generally makes the operation a little harder. Theoretically, the patella tracking and quadriceps muscle strength may be temporarily improved with this approach in the short term, but there are no long term differences months later.
Quad-Sparing Approach
The quad-sparing approach cuts just the inside of the knee cap. This approach requires special side cutting instruments. There is definitely a steep learning curve regarding the use of these instruments and many physicians (including myself) worry about the accuracy of the bone cuts and limb alignment with these side cutting instruments. This approach has received some press, but has not caught on among orthopedic surgeons.
Lateral parapatellar Approach
The lateral parapatellar approach is a uncommon approach where the incision extends around the outside (lateral) of the knee cap. Some surgeons will use this approach for severe valgus deformities.
Good results after a total knee replacement can be achieved with any of the above approaches. Patients should allow the surgeon to perform the approach the surgeon is most comfortable with.
A total hip replacement is one of the most successful operations that orthopedic surgeons perform. A hip replacement is an elective surgery, which means patients decide if and when to have their hip replaced. As a physician, I never tell patients they have to have a hip replacement surgery, but many times surgery may offer the only possibility for pain relief. Although the surgery is elective, it is covered by most insurance companies; however, depending on your policy you maybe required to make a small co-payment. My philosophy is to give my patients as much information as they need to make informed decisions regarding their health and hip pain and then treat their hip pain according to their wishes.
A hip joint is basically a ball and socket joint. A hip replacement involves removing the ball (femoral head) and replacing it with a metal prosthetic ball. The femoral prosthesis is inserted into the hollow part of the femoral shaft. The socket of the pelvis is machined into a hemisphere and a metal hemisphere is inserted into the socket. The new metal ball and new metal socket form the new hip joint and allow the same and often times more motion than the native hip joint. The femoral and acetabular prosthesis are attached to your bones by creating a space in the bone that is slightly smaller than the metal prosthesis and then pressing the metal prosthesis into this tight space. Occasionally, the metal prosthesis is attached to the bone with bone cement. The parts are made of stainless steel, titanium, ceramic and/or polyethylene. I typically make an incision about 3-4 inches long for a hip replacement.
The purpose of this web page is to educate patients about the major aspects of hip replacement surgery. Many studies have shown that an informed patient will have less surprises and more satisfaction with their surgery. I do not intend to scare people away from getting their hip pain treated. Although the following information is a reasonable overview of what I consider the major aspects of hip surgery, it is not a substitute for a clinical consultation where I can directly answer your questions. If you would like more information, please schedule an appointment to see me.
Knee replacements are preformed through an incision on the front of the knee. There are some different ways to handle the soft tissue and extensor mechanism of the knee which are discussed below. Each approach has advantages and disadvantages.
Medial Parapatellar Approach
A medial parapatellar incision involves cutting the quadriceps tendon above the knee cap (patella) and around the inside (medial) of the knee cap. The tendon is then repaired at the end of the procedure. The idea behind cutting the tendon is that the tendon might heal better than cutting into the muscle belly of the VMO. The patella is typically flipped during this approach to gain access to the knee joint which may or may not affect the knee rehab in the short term.
Mid-Vastus Approach
A mid-vastus approach does not cut the quadriceps tendon but instead cuts into the VMO muscle belly and around the inside of the knee cap. The idea behind leaving a large portion of the VMO attached to the quadriceps is that the VMO muscle may help patellar tracking and knee extension strength. The muscle belly is repaired at the end of the procedure. The patella may or may not be flipped during this approach.
Sub-Vastus Approach
The sub-vastus approach elevates the VMO muscle instead of cutting into it. The incision then extends around the inside of the knee cap. The patella is typically not flipped with this approach. This approach is difficult in muscular patients with large VMO muscles and generally makes the operation a little harder. Theoretically, the patella tracking and quadriceps muscle strength may be temporarily improved with this approach in the short term, but there are no long term differences months later.
Quad-Sparing Approach
The quad-sparing approach cuts just the inside of the knee cap. This approach requires special side cutting instruments. There is definitely a steep learning curve regarding the use of these instruments and many physicians (including myself) worry about the accuracy of the bone cuts and limb alignment with these side cutting instruments. This approach has received some press, but has not caught on among orthopedic surgeons.
Lateral parapatellar Approach
The lateral parapatellar approach is a uncommon approach where the incision extends around the outside (lateral) of the knee cap. Some surgeons will use this approach for severe valgus deformities.
Good results after a total knee replacement can be achieved with any of the above approaches. Patients should allow the surgeon to perform the approach the surgeon is most comfortable with.
