A. The surgical replacement of only one part of the damaged or diseased knee joint is known as partial knee replacement surgery or partial knee arthroplasty.

A. The knee joint is a type of hinge joint present at the junction of the thigh bone (femur) and shin bone (tibia). It is made up of ligaments, tendons, cartilage, lubricating fluid, and patella (kneecap).

A. A partial knee replacement surgery may be performed in the following situations:
Osteoarthritis: The wear and tear of the knee joint due to the breakdown of the cartilage (cushion between the knee and bone joints) is known as osteoarthritis. It occurs due to an increase in age.
Rheumatoid arthritis: The immune or disease-fighting system of the body attacks the lining of the knee joint in this condition.
Post-traumatic arthritis: A knee joint injury may be treated by a partial knee replacement surgery.
Moderate knee deformity: When the knee deformity affects only one side of the knee joint, a partial knee replacement surgery may be needed for treatment.

A. The following symptoms seen in a patient could indicate the need for a partial knee replacement surgery:

• Severe knee pain that prevents a person from sleeping at night
• Severe knee pain that prevents a person from performing his/her daily activities
• Stiffness of the knee joint 
• Minor knee deformity 
• Failure of other treatment options

A. Total knee replacement surgery involves the replacement of all the compartments of the knee joint, while partial knee replacement surgery involves the replacement of only one part of the damaged knee joint.
A partial knee replacement surgery is preferred over a total knee replacement surgery in the following cases:
Arthritis affecting only one side of the knee joint
Stable ligaments in the knee joint area
Good range of motion of the knee joint
Minor deformity in the knee 
 
 

A. The different types of partial knee replacement surgeries include:

1. Unicondylar knee replacement: It involves the replacement of a single knee compartment, that is, either the medial (inside) compartment or the lateral (outside) compartment.
2. Patellofemoral knee replacement: It involves the replacement of the diseased or worn patella (kneecap) and the trochlea (a groove present at the end of the femur).
3. Bicompartmental knee replacement: It involves the replacement of two knee compartments, namely the medial and the patellofemoral compartments.

A. Partial knee replacement surgery is generally performed by an Orthopedic Surgeon.

A. The following diagnostic tests may be performed before a partial knee replacement surgery procedure:

1. Physical examination: The doctor evaluates the mobility of the knee joint and the soft tissues around the knee joint. The patient’s medical history and symptoms are noted.
2. Chest x-ray: The condition of the heart and lungs can be checked by the doctor using a chest x-ray.
3. X-ray of the knee joint: It helps the doctor to check for the presence of any deformity in the knee joint area.
4. Imaging tests: Imaging tests such as CT scans and MRI scans help in obtaining a clear image of the bone defect present in the knee area.
5. Blood tests: The various blood parameters and certain underlying medical diseases can be checked using blood tests.
6. Urine tests: These tests help the doctor to check for certain infections that may be present.
7. Electrocardiogram (ECG): The electrical activity of the heart can be measured using this test.

A. The following preparation may be needed before a partial knee replacement surgery:
Inform the doctor about any medical disorders that you may be having.
Inform the doctor if you are taking any supplements, herbs, or medications.
Tell your doctor if you have any allergies.
Try and quit smoking as soon as possible.
The doctor may tell you to stop taking blood-thinning medications like warfarin and aspirin a few days before the procedure.
You will not be allowed to eat or drink anything after midnight the day before the surgery.

A. A partial knee replacement surgery is performed as follows:

• The surgery is normally done under general anesthesia (the patient is put to sleep before the procedure).
• An incision or cut is made in the front portion of the knee joint.
• The surgeon has access to all the three knee joint compartments and can now approach the affected compartment of the diseased or damaged kidney.
• The damaged cartilage and bone are removed by the doctor from the respective knee joint compartment.
• The removed part is substituted using metal coverings to recreate the knee joint surface.
• A cement is used to hold the prosthetic implants to the bone.
• A plastic insert is placed between the two metal components to create a smooth gliding surface and avoid friction, which is the normal function of the cartilage.
• The incision is now closed using sutures or stitches.
• The procedure is completed in approximately one to two hours.

A. The following are the post-procedure steps after a partial knee replacement surgery:

• The patient is usually discharged from the hospital one or two days after the surgery.
• It is normal to have some soreness and swelling after the surgery.
• Physiotherapy sessions are recommended for two to four weeks after hospital discharge to help in the mobilization of the knee joint.
• A walker or crutches may be used by the patient for some time after the surgery.
• Most of the patient’s daily activities can be resumed approximately six to eight weeks after the surgery.
• Regular follow-up sessions with the doctor are mandatory to check for the results of the surgery.