When your knee doesn’t respond to medications and treatments, knee replacement surgery is an option. There are two types of replacement surgeries: total knee replacement, the more commonly performed of the two, and partial knee replacement.
Total knee replacement
The traditional method for repairing a damaged knee is a total knee replacement surgery (TKR).
Since the first operation in 1968, doctors have dramatically improved the procedure. In fact, advancements in medical technology have led to precise and highly functional artificial knee implants that nearly duplicate the way the human knee moves — and are custom fit to your body. A TKR is now among the safest and most effective of all standard orthopedic surgeries.
During a TKR, a surgeon removes the surface of your bones that have been damaged by osteoarthritis or other causes and replaces the knee with an artificial implant that is selected to fit your anatomy. The surgeon uses special surgical instruments to cut away the arthritic bone accurately and then shapes the healthy bone underneath to fit precisely into the implant components.
Essentially, the surgery is a four-step process. The first part involves preparing the bone by removing the damaged cartilage surfaces at the ends of the thighbone (femur) and shinbone (tibia), as well as a small portion of underlying bone.
Types of knee replacement approaches
Your doctor will also choose a surgical approach (as well as the approach to anesthesia, whether general or regional) that’s best suited to your needs. You and the medical team will engage in pre-operative planning that covers the type of procedure you receive and associated medical requirements.
In order to ensure a smooth procedure, a skilled orthopedic surgeon will map out your knee anatomy in advance so that they may plan their surgical approach and anticipate special instruments or devices. This is an essential part of the process. Possible procedures are discussed below.
In the traditional approach, the surgeon makes an 8- to 12-inch incision and operates on the knee using standard surgical technique. Generally, the incision is made along the front and toward the middle (midline or anteromedial) or along the front and to the side (anterolateral) of the knee.
The traditional surgical approach usually involves cutting into the quadriceps tendon in order to turn the kneecap over and expose the arthritic joint. This approach typically requires three to five recovery days in the hospital and about 12 weeks of recovery time.
Minimally Invasive Surgery
A surgeon may suggest a minimally invasive surgery (MIS) that reduces trauma to tissue, lessens pain, and decreases blood loss — consequently speeding recovery. A minimally invasive approach reduces the incision to 3 to 4 inches. A key difference between this approach and the standard surgery is that the kneecap is pushed to the side rather than being turned over. This results in a smaller cut into the quadriceps tendon and less trauma to the quadriceps muscle. Because the surgeon cuts less muscle, healing occurs faster, and you are likely to experience better range of motion after recovery.
The procedure modifies the techniques used in traditional surgery while using the same implants from traditional surgery. Manufacturers provide specialized instruments that help to place the implant accurately but also allow for incisions to be made as small as possible. Since the only change between MIS and traditional surgery is in the surgical technique, the long-term clinical outcomes are similar.
Types of minimally invasive approaches include:
. Quadriceps-sparing approaches
After making a minimal incision, the surgeon shifts the kneecap to the side and cuts away the arthritic bone without cutting through the quadriceps tendon. The quadriceps-sparing method, as the name suggests, is less invasive than traditional surgery. It spares the quadriceps muscle from as much trauma as possible.
Another term for this approach is “subvastus” because access to the joint is taken from under (sub) the vastus muscle (the largest part of the quadriceps muscle group).
Another variation of a quadriceps-sparing approach is called midvastus. It also avoids cutting the quadriceps tendon, but instead of completely sparing the vastus muscle by going under it, in this surgical approach the muscle is split along a natural line through the middle. The decision to use one approach versus another depends on the condition of your knee and surrounding tissues.
The subvastus and midvastus approaches often take longer to perform but may result in a faster rehab process. This is because there is little to no trauma to the underlying thigh muscle, making it easier to walk sooner after the operation.
. Lateral approach
This approach is rarely used. It’s more common for those whose knees tend to bend outward. The surgeon enters the knee joint laterally, or from the side of the knee. The lateral approach is less invasive than traditional surgery because it spares much of the quadriceps, making it easier for patients to return to walking faster.
Minimally invasive surgery trims the hospital stay to three to four days and it can shorten the recovery period to four to six weeks. People who get a PKR experienced less pain and were able to resume daily activities faster and better than those who had standard surgery. At one year, however, there were no significant differences between the two groups.
Minimally invasive approaches aren’t appropriate for everybody. Surgeons carefully evaluate each patient and select the approach that’s best. Also, minimally invasive surgery is more difficult to perform and requires a more specific technique, instruments, and surgical training. One study found that it requires about one hour longer than a traditional surgery. Consult your surgeon to discuss your options.
. Computer-assisted surgery (CAS)
Increasingly, surgeons are also turning to computer-assisted methods for both TKRs and PKRs involving both traditional and minimally invasive procedures. A surgeon enters a patient’s anatomical data into a computer — a process called “registration” — and the computer generates a 3-D model of the knee.
The software provides the surgeon with a more precise, computer-aided image of the knee. The computer helps the surgeon align the knee components more precisely in the bone and increases the odds that the device will work effectively.
A computer-based approach also allows a surgeon to operate with a smaller incision and benefits the patient by reducing recovery time. A more precise fit can also reduce wear and increase the longevity of the new joint.
About Iranian Surgery
Iranian surgery is an online medical tourism platform where you can find the best orthopedic surgeons in Iran. The price of Total Knee Replacement Surgery in Iran can vary according to each individual’s case and will be determined by an in-person assessment with the doctor.
For more information about the cost of Total Knee Replacement Surgery in Iran and to schedule an appointment in advance, you can contact Iranian Surgery consultants via WhatsApp number 0098 901 929 0946. This service is completely free.