What is a TKR?
A knee replacement is also called knee arthroplasty and can be described as a resurfacing as only the surface of the bones of the joint are replaced. After surgery there is pain relief and this improves the ability to walk. A TKR needs hospitalization for 3-5 days. The procedure is one under general anesthesia or spinal anesthesia or a combination of both
A TKR involves removing the end of a thigh bone and the top of the shin bone and resurfacing them with artificial knee implants, which is made of metal alloy and high density plastic. The thigh bone surface (femoral componenet) is made of curved polished metal, the surface of the shin bone is covered with high density plastic and the knee cap is plastic.
The surgery takes 1-2 hours. After surgery the patient will be in the recovery room till the anesthesia recovery criteria is met
Steps Involved in the Surgery
Step 1: Preparation: the damaged cartilages covering the lower end of the thigh bone and upper end of the shin bone are removed along with a few millimeters of underling bones
Step 2: Positioning metal implants: The removed cartilage and bone are replaced with metal components to recreate the joint surface. These are cemented into the bone with methyl metacrylate or special coatings which encourage bone growth
Step 3: Resurfacing the knee cap: The undersurface of the knee cap is cut and resurfaced with a plastic part. This step may not be done depending on the need
Step 4: Inserting a spacer: A medical grade plastic spacer is inserted between the metal components to create a smooth gliding surface
Who Needs Surgery?
- Those with severe knee pain or stiffness which limits mobility and therefore affects normal life
- Difficulty in performing daily activities like walking, climbing stairs, getting up from a chair or sitting down, support in the toilet etc
- Moderate to severe pain even at rest, often leading to disturbed sleep
- No respite from symptoms despite medicines, rest, physiotherapy or use of walking aids
- Knee deformity like bowing of legs
- Failure of treatment such as anti-inflammatory drugs, cortisone injections, lubricant injections, physiotherapy or other surgeries
How to Ensure Good Results of Surgery?
- Weight loss in those who are overweight
- Adherence to physiotherapy regimen
- Adequate and correct exercises