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Searching for Knee Replacement Surgery?
This article helps you to know more about “Knee Replacement Surgery”
If you are severely suffering from knee pain your surgeon will suggest going for a knee replacement surgery.
Generally, knee replacement surgeries can be classified into two categories
Total Knee Replacement Surgery:
Total Knee Replacement Surgery which is abbreviated as TKR Surgery refers to replacing the surfaces of the knee with plastic and metal implants.
Total Knee Replacement is a surgical procedure wherein the diseased knee joint is replaced with the artificial material called an implant. The knee is a hinge joint which provides motion at the point where the thigh meets the lower leg. The thighbone (or femur) abuts the large bone of the lower leg (tibia) at the knee joint.
Total Knee Replacement Procedure:
Knee replacement procedure involves the following steps
Evaluation before surgery:
An evaluation with an orthopedic surgeon consists of several steps
- Medical history: An orthopedic surgeon will gather information about the patients’ general health and ask about the extent of your knee pain and your ability to function.
- Physical examination: This will assess knee motion, stability, strength, and overall leg alignment.
- X-rays: These x-ray images help to determine the extent of damage and deformity in the knee joint.
- Imaging investigations: Advanced imaging such as a magnetic resonance imaging (MRI) scan, may be needed to determine the condition of the bone and soft tissues of the knee joint.
- Other tests: Occasionally blood tests, blood pressure, and sugar investigations.
Generally, a patient who has planned for the knee replacement surgery will be most likely admitted to the hospital on the day of the surgery or on the day before the surgery.
Post admission the patient will be re-evaluated for clinical parameters like BP, sugar, etc. And also the patient will be evaluated with the Anesthesia team before the surgery to determine which type of Anesthesia to be used for the patient. Commonly the types of anesthesia are general anesthesia (you are put to sleep) or spinal, epidural, or regional nerve block anesthesia (you are awake but your body is numb from the waist down).
The patient will be moved to the operation theatre and the patient will be under general/regional anesthesia at the time of the knee replacement surgery.
The knee replacement surgery procedure will approximately take around 1 to 2 hours. In this procedure, the orthopedic surgeon will remove the damaged cartilage and bone, and then position the new metal and plastic implants to restore the alignment and function of your knee.
The typical knee replacement surgery procedure involves the following steps:
- An orthopedic surgeon makes an incision (a cut) on the front side of the knee which helps to expose your knee cap. Later it is moved to the side so the orthopedic surgeon can get to the knee joint.
- The damaged ends of the thigh bone (femur) and shin bone (tibia) are carefully cut away. The ends are precisely measured and shaped to fit the appropriately sized prosthetic replacement called as an implant. A dummy joint is positioned to test that the joint is working properly. Adjustments are made, the bone ends are cleaned, and the final prosthesis is fitted.
- The end of the femur is replaced by a curved piece of metal, and the end of your tibia is replaced by a flat metal plate. These are fixed using special bone ‘cement’, or are treated to encourage the bone to fuse with the replacement parts. A plastic spacer is placed between the pieces of metal. This acts like cartilage, reducing friction as the joint moves.
- At MaxCure Hospitals, surgeons prefer computer navigation technique to perform the knee replacement surgery. This will provide approximately 100% accuracy in placing the implants. Also with more than 99% of the success rate. This computer navigated technique will also help the patient to walk within 3 hours* after his knee joint replacement surgery.
- The incision is closed with either stitches or the clips. A dressing is applied to the wound.
After knee replacement surgery, the patient will be taken to a recovery room for several hours while the surgical anesthesia wears off. Afterwards, the patient typically is taken to a hospital room where he or she will spend 3 to 7 days before being discharged.
The surgeon prescribes a course of physiotherapy and post-surgical investigations to understand the performance of the newly implanted knee and for evaluating the post-surgical complications.
Partial Knee Replacement Surgery:
Partial Knee Replacement Surgery which is abbreviated as PKR / UKR (Unicompartmental Knee Replacement) Surgery refers to replace only one part of the damaged knee. It can replace either the inside (medial) part, the outside (lateral) part, or the kneecap part of the knee.
There are three types of Partial Knee Replacement
Unicondylar Knee Replacement is a procedure that replaces only the single affected compartment of the knee, either the medial or lateral compartment.
Patellofemoral Knee Replacement is a procedure that replaces the worn patella (the kneecap) and the trochlea (the groove at the end of the thighbone).
Bicompartmental Knee Replacement is a procedure that replaces two compartments of the knee, the medial and patellofemoral compartments.
The surgical procedure for partial knee replacement will be similar to the total knee replacement. In total knee replacement surgery, the complete part of the join is been replaced with the implant wherein partial knee replacement surgery only the affected part of the knee joint will be replaced with implants.
Advantages of partial knee replacement over total knee replacement:
Compared to total knee replacement, partial knee replacement better preserves range of motion and knee function because it preserves healthy tissue and bone in the knee. For these reasons, patients tend to be more satisfied with partial knee replacement compared with a total knee replacement. They are still candidates for total knee replacement should they ever need it in the future.
There is also less blood loss during surgery, and knee motion recovers faster with a partial knee replacement.
Risks and complications of knee replacement surgery:
The majority of patients will recover well from their knee surgery without any significant problems. As with all surgical operations, there are some risks that might occur and these include:
- Deep vein thrombosis and pulmonary embolus
- Pain following TKR
- Excessive bleeding
- Tendon, nerve or blood vessel damage
- Revision surgery
- Dislocation of the bearing (specific to PKR)
- General Risks
Surgery is carried out under strict sterile conditions in an operating theatre. Antibiotics are administered intravenously at the time of the surgery. (Any allergy to any known antibiotics should be brought to the attention of your surgeon or anesthetist).
Despite these measures, there is still a chance of developing an infection but this is less than 1%. Infections may require further hospitalization and treatment. Sometimes they necessitate the removal of the knee replacement for a period of time; antibiotics are administered via a drip for a few weeks (during this period you may be able to go home). Following this, another knee replacement may be re-implanted.
Deep vein thrombosis:
All surgical operations on the lower limb carry a risk of blood clots forming in the deep veins of the leg, and occasionally in the lungs. We take precautions during and after the operation to try to minimize this risk. A combination of immobilization of the limb, smoking and the oral contraceptive pill or hormonal replacement therapy all multiply to increase the risk of a blood clot. Any past history of blood clots should be brought to the attention of the surgeon prior to your operation. The oral contraceptive pill, hormonal replacement therapy, and smoking should cease 6 weeks prior to surgery to minimize the risk.
Sometimes the knee becomes stiff after surgery (1%) due to scar tissue forming inside the knee. If this happens the knee may require a manipulation under a second general anesthetic to help regain movement.
Pain following TKR:
In 20-30% of cases patients still, have some discomfort from the knee. In a few cases, pain in the knee is severe and the joint is very sensitive. In this case, further hospital care may be required.
Inevitably some blood is lost at the time of surgery. Sometimes people lose larger volumes of blood and a transfusion may be required. Bleeding is more likely to occur with patients taking aspirin or other anti-inflammatory drugs. They should be stopped at least one week prior to surgery.
Tendon, nerve or blood vessel damage:
Very rarely these structures can be injured during the operation. Normally they recover, but occasionally patients may experience extensive bruising or have difficulty moving their foot up and down. Often after a knee replacement patients have a small patch of numbness to the outside of the scar due to small nerves in the skin being damaged; this normally does not cause problems and often diminishes with time.
Over time the components of the knee replacement can wear out or become loose. This normally presents with worsening pain and may require further surgery to replace the joint components.
Dislocation of the bearing (specific to PKR):
The PKR has a mobile plastic bearing. Rarely this can dislocate and require further surgery to reposition it (<1%).
After any general anesthetic, there is always a risk of developing a chest infection. This risk can be minimized by early mobilization and performing deep breathing exercises after surgery. If you have any history of respiratory problems you should inform the staff at the hospital.
Any major operation carries small risks of stroke or heart attacks. These risks are small but very dependent on the patient’s general health and lifestyle prior to the operation.
1. Peripheral Nerve Blocks Improve Analgesia After Total Knee Replacement Surgery, Click: https://journals.lww.com/anesthesia-analgesia/Abstract/1998/07000/Peripheral_Nerve_Blocks_Improve_Analgesia_After.20.aspx
2. Comparison of a Generic and a Disease-Specific Measure of Pain and Physical Function after Knee Replacement Surgery, Click: http://www.jstor.org/stable/3766620
3. A Comparison of Four Models of Total Knee-Replacement Prostheses, Click: https://link.springer.com/chapter/10.1007/978-1-4471-5451-8_41/fulltext.html