To truly spare the quadriceps tendon from any cutting, a different variation of minimally invasive surgery, called quadriceps-sparing knee replacement, can be used. This surgical approach is not new. Another name for it is the subvastus approach. “Subvastus approach” means going under the vastus muscle, which is part of the quadriceps muscle group. In essence, the surgeon makes a small (3- to 4-inch) skin opening. Next, the surgeon opens a fibrous layer of tissue (called the retinaculum) attached to the quadriceps muscle. and enters the knee joint. Finally, to expose the knee joint enough to insert the replacement, the surgeon takes the cut in the retinaculum further up into the thigh. This is done without cutting or injuring the quadriceps tendon. The quadriceps muscle is instead lifted up out of the way, so special instruments can be positioned for the operation.
he incision for the quadriceps-sparing knee replacement is only as large as is necessary to place the replacement parts in the body. The cut into the skin is shorter, and the underlying cut to reach the bone through the deep tissues is also shorter than for standard knee replacement surgeries, so the quadriceps is not cut. Special instruments are used to access and prepare the bone through such a small incision. Implants designed for this type of procedure and occasionally X-ray guidance are also used for this surgery. This surgery is best performed by experienced surgeons with special training in this procedure.
This type of surgery cannot be performed on all people. Surgeons carefully select people for whom this procedure is possible. Yet most people who are candidates for total knee replacement are suitable for this procedure.
Results after quadriceps-sparing knee replacement are generally dramatically better than results after knee replacements performed through a 4-inch incision using the standard technique. Benefits include an early return to walking, greatly reduced pain, and a remarkably different overall recovery. Scarring and soft tissue trauma underneath the skin are minimal.