I ASSIST Verilast Knee replacement – Knee replacement meant to last 30 years.
Are you young and need a knee replacement? Are you scared to get it because you think it won’t last through out your life? If so take heart!
Knee replacement in young patients can now last for thirty years. This is due to the novel combination of a new smart tool, ‘I-Assist’ and a durable implant ‘Verilast knee’. Dr.Venkatachalam uses this combination for operations in young patients. “This novel combination will ensure that the perfectly aligned knee will last for at least thirty years” says Dr.A.K.Venkatachalam. He performed this novel procedure on a thirty two year old woman in India. It is for the first time in the world that the I-Assist tool was used to implant a Verilast knee.
Case report–
Ms Payal, a thirty two year lady from Gujarat was suffering from a rare condition called ‘Avascular necrosis‘. There was extensive damage to her knee. Although she was young for a knee replacement, the surgeon had no other option. He decided to use the Verilast CR knee and the I-Assist. He had recently introduced the I-Assist device in Chennai for another patient. He had been working with the Oxinium knee for several years now. He was reponsible for ushering in this technology in 2008. Earlier Dr.Venkatachalam had used computer navigation and patient specific instruments to implant difficult knees. This was the first time in the world that the I-Assist tool was used to implant a Verilast knee.
Why did he choose this?
The Verilast knee
Based on laboratory wear simulation testing, the LEGION* cruciate retaining (CR) knee system with VERILAST technology is expected to provide wear performance sufficient for 30 years of actual use under typical conditions.
VERILAST Technology uses advanced, low-friction surfaces for both sides of the knee joint, the femur bone of the thigh and the tibia bone of the lower leg. It combines Smith & Nephew’s award-winning OXINIUM* Oxidized Zirconium metal alloy and a “cross-linked” plastic component (XLPE), which together has been shown in laboratory testing to more than double the wear performance of the LEGION* CR knee replacement.
OXINIUM Oxidized Zirconium is a tough, smooth metal with a ceramic surface 4,900 times more abrasion resistant and 20 percent lighter than the cobalt chrome metal used in other implants.
- The ceramic surface is created through a manufacturing process where oxygen is naturally diffused into the zirconium metal as it is heated in air. The original metal surface is literally transformed into a ceramic; it is not an externally applied coating
- With no detectable amounts of nickel, the metal most associated with allergies, OXINIUM is a biocompatible material for implants.
- This proprietary material has been used in more than 250,000 knee implants.
Research shows unprecedented reduction in Wear.
In laboratory testing, the LEGION CR knee with VERILAST Technology was compared against a similar knee made from conventional materials (cobalt chrome and standard plastic). The results showed that:
- After five million cycles, or simulated steps, the LEGION CR knee reduced 98 percent of the wear experienced by the knee made with traditional implant materials.
- When the knee with VERILAST Technology kept “walking” out to 45 million cycles, it reduced 81 percent of the wear experienced by the conventional knee implant that was stopped after the first five million cycles. 45 million cycles is equivalent to about 30 years of physical activity.
I-Assist smart tool
‘I-Assist’ is a smart tool designed to improve the accuracy of a total knee replacement. It assists the surgeon in aligning knee implants to each person’s unique anatomy. The outcome is very predictable as perfect alignment is achieved intra operatively.
How it works:
It uses electronic components in a palm sized device. With the I-Assist, the surgeon can align and validate implant positioning during total knee replacement.
Which type of knee replacement patients’ benefit most from this technology?
It is of great value primarily to young patients undergoing total knee replacement. The durability of a knee replacement is dependent upon the alignment. As younger patients will survive longer after a knee replacement, it is crucial to get the first knee replacement perfectly aligned. This will reduce the need for a redo or revision knee replacement. Revision surgery is difficult and expensive.
A sizeable number of young patients have additional complications in the leg that make a knee replacement difficult. Patients from Asia and Africa present with malunited thigh and leg fractures secondary to a previous accident. They have developed post traumatic knee arthritis as a result of these accidents. Bony deformities within the knee and outside preclude use of all previous modes of instrumentation.
The ‘I-Assist’ system is the only system that allows accurate alignment in these complicated and difficult cases.
In summary, a pedigree implant, the ‘Verilast knee’ and new smart tool, ‘I-Assist’ can guarantee a durable outcome.
About the author:
Dr.A.K.Venkatachalam specializes in joint replacements and key hole surgery. He has performed knee replacement in several patients with durable materials and advanced techniques. This is the first time that the I-Assist smart tool and the verilast knee replacement have been used together.
To know more about Total knee replacement and other knee procedures, visit www.kneeindia.com
See an Indian patient’s story here
To get this procedure for your self e mail drvenkat@kneeindia.com