Know more about Knee Replacement Implants.

Hello friends. My name is Dr. M.S. Narula. I am a senior consultant orthopedics and joint replacement surgeon. Now, we will talk about total knee replacement. As I have explained, total knee replacement is much more commonly done than total hip replacement especially happens in elderly people, since hip replacement is done in the younger population. Unless there is a fracture. Knee replacement is done in above 50 or 55 years. If I talk about this, implants broadly are of different types. It has three components. One component is fit in the lower bone. Nowadays, we have the latest technique, resurfacing means we don't cut the bone, only peel off the thin layer of the tibia of the bone. It's like we don't deeply cut the bone; there are bone preserving surgeries. There is minimum bone cutting. Lower bone is called the tibia. We just peel it like a pencil, thin layer, just a few mm and shape it like this. This implant has a tray above it. This tray and plastic are separated, as it is a model. We fix this tray with cement over the bone. Similarly, we have an upper bone called Fermor, also resurfaced in a special shape as you can see it has been cut in a particular shape. We fix this implant with the cement on the upper bone, and we insert a small plastic inside and this is a complete implant where one is an upper component, the Fermor component, other is the tibia component which is lower bone and plastic is inserted in between. This is how it articulates. So those two bones have worn out, and the gap has been finished. We have again made a gap, and if you observe from an aside, this is how it moves. So what are the advances in this? Earlier, when we used to do knee replacements, their life expectancy used to be around 14, 15, or 16 yrs. Now, the implants last for at least 25 to 30 years and sometimes even beyond. So how has it become possible? Firstly, designs of implants have become better, and the Indian population has expectations or requirements that we like low seating position, cross-legged so the newer designs, especially in the Asia Pacific, for the Indian population, which has a high flex design so that there is more and flexible knee movement so that we can sit on the floor cross legged. Although we tell our patients to avoid movement as much as they can after knee replacement. so high flex design, so those who have design can move quickly. Wear and tear of the plastic insert due to which this joint becomes loose easily. There is a lot of improvement in the quality of plastic, high-density polyethylene, which is very dense and strong so that this plastic part does not get damaged easily. Then this metallurgy, the quality of metal, cobalt-chromium alloy has improved a lot. Some additions have been done, such as titanium or gold plated, but cobalt-chromium is still a gold standard in present times. With little modifications, attempts have been made to make implants more smooth and strong to slow down their wear and tear, and of course, bringing in more movement is the most important thing. So, more companies have introduced gender-specific for males and females depending on the shape of bones. Of course, there is a customised prosthesis, where some implants are designed according to your shape with ct scan, which is a bit expensive and cumbersome and rarely used. But most of these companies have come out with newer designs with small increments so that they become as close to your normal bones. They are fit with your normal bones, you have more movement, should be painless so that there is no impingement of muscles and bones, and of course with good life expectancy to slow down the wear and tear. Knee replacement is now a very safe and predictable surgery. It is a very gratifying surgery; if done in good times, it gives you very, very good results in the hands of an experienced surgeon. One more advancement I would like to mention which we call uni since, in normal knee replacement, these two compartments are changed. In uni, there is partial knee replacement, in which we replace the inner portion that has been worn out, we use a half implant, but that is only possible if the patient visits us in the early stage. Most Indian people visit us at the stage where we have to do a total knee replacement, but in total knee replacement, there are many advances as I have explained resurfacing where a thin layer of bones are cut called bone preserving surgeries. So a combination of well-done surgery, timely selection of the patient, and a good implant give very, very good results in the hands of an experienced surgeon. Take care and stay safe.

[@umajain4025]

Nicely removed my confusion ❤

[@badrinathgumperla1855]

Well explained about knee replacement. Thanks ji.

[@rajdeepsethia1984]

Hello sir, am a hemophilic, my age is 39 I stay in bangalore, I am going for TKR. PLEASE suggest me which company implant should I go with, so that I can refer my Surgeon

[@brijeshrudani1764]

Thanks 🙏🏻

[@DeepKumar-qm3bd]

Cost ki hai chokri bale knee

[@shrikantkumar8984]

AYu health Wale sab ka bebkup banate hai ....