8, March 2010
By Sumi Sukanya
New Delhi, India
The patient, 40–year–old Rita Verma, was able to walk within 24 hours of the operation. In complete knee–replacement surgery, a patient cannot walk for at least a week after the surgery.
Said Verma, “I have had a bad knee for the last few years. Three years ago I underwent cleaning of the joint. Then I fell while dancing, after which my knee would go so stiff at times that I thought I would never be able to walk again.”
Unlike complete knee–replacement surgery – which is suitable for older people because of the wear and tear to their knees and the possible need for ‘revisory’ surgery – this operation suits younger patients better because they keep the original knee, and so flexibility of the knee is not affected.
Said Dr J Maheshwari, chief joint replacement surgeon at the hospital, “There are two joints in the knee. They are the major joint (between the thigh bone called the femur, and the leg bone called the tibia) and the minor joint (between the femur, and the knee cap called the patella). While damage to the major joint is treated with complete or partial knee–replacement surgery, depending on the extent of damage, arthritis affecting the patello–femoral part of the knee joint is difficult to treat, and the only treatment known so far is complete knee replacement. But it is not logical to replace the entire knee when only a small part is affected.”
He added, “Since these patients are often young, complete knee replacement is not a good option. With advances in isolated patello–femoral replacement technology – where artificial caps are put on the damaged parts of the smaller patello–femoral part of the knee – an arthritic patient will now be able to continue to use his or her original knee.”
Experts say there are a number of patients suffering from damaged patellofemoral joints, which are difficult to diagnose with routine x–rays. Typically, these patients are younger, between 40–50 years of age. Their knees hurt when they climb stairs but not when they walk on level surfaces.
In the operation, Maheshwari said, the knee is opened, the worn out surfaces of the patello–femoral joint are first scraped even and then covered with artificial caps made of steel and plastic. In this way, friction between the surfaces is reduced, giving the patient relief from pain. The knee itself is essentially left as it is.
Young Patients Can Benefit
Whom will the surgery benefit? About 3% of people suffering from arthritis that has damaged their knee joints
How is the surgery carried out?
- A 5–inch incision is made in the front of the knee
- The knee cap (patella) is shifted to one side
- The damaged portion of the thigh bone is cleaned and space is created in the damaged bone, in which to fit the artificial cap
- The cap is then fitted with bone cement
- The underside of the patella is shaved and replaced with a plastic cap
- The new joint is put back in place and the skin stiched back on
- Beneficial for young patients, suffering damage in the minor joint in the knee as it does not affect flexibility of the knee
- If, after a few years, complete knee replacement is required, it can be done easily, unlike with traditional surgery in which revision of the original surgery becomes difficult