i-assist personalized knee replacement in india
DESCRIPTION
The I-Assist personalized guidance system gives perfectly aligned knee replacements which prolongs the life of the implant. You the patient don't have to worry about your knee wearing out in the rest of your life. Get it done with once and enjoy restored mobility for the rest of your life.TRANSCRIPT
I-Assist personalized guidance system
Dr.A.K.VenkatachalamMS Orth, DNB Orth, FRCS, M.Ch Orth
Consultant Orthopaedic surgeon
www.kneeindia.com
Alignment in Knee replacement• It is one of the factors that
ensures long life of the implant.
• A proper alignment means the implant is perpendicular to the ground.
• Mal aligned knee replacements tend to wear out sooner than normal.
• Even experienced surgeons can make errors in placement of the components.
Mal-aligned car tyre
Wear on the inside
Our patient • Mrs.Lakshmamma, Housewife, Age- 55 years• Resident of Guntur district, Seemandhara• Had both knee replacements on 7/8/14 and
13/8/14 • Female special, Full bending knee implants
with• Prolong Poly insert – capable of long life.
Post op progress
• The patient started walking on the next day after surgery on both knees.
• Post - op X-rays of both knees show perfect alignment which was made possible by the I-Assist device.
What is the I-Assist?
• It is a Personalized guidance system designed to assist the surgeon in positioning a total knee arthroplasty implant components intra operatively.
• It uses surgical instruments and position sensors to determine alignment axes in relation to anatomical landmarks
• To thus precisely position alignment instruments & implant components relative to these axes.
What is inside it?
• It consists of 4 half palm sized pods with electronic apps like
• Wi-Fi found in smart phones. • Gyroscope found in air planes. • The electronic sensors inside calculate the
alignment. The blinking lights on the display face indicate the correct position.
• Red light means improper position and Green light means proper position.
How does it work?
• After connecting it to the knee the surgeon moves the femur in 13 different positions and the tibia in 4 positions.
• It calculates the position by the electronic devices inside it.• The surgeon makes fine adjustments so that red lights turn to green. • Blinking green lights indicate zero percent error. • The surgeon can proceed to cut the bone confident that his
cuts will be perfectly aligned. • He can then finally place the implant components in the
correct alignment achieved and validated in the previous steps.
Advantages
• It guides the surgeon to get perfectly aligned cuts intra operatively.
• It gives zero error cuts and again validates it in the next step.• Thus the surgeon gets the right fit during the surgery itself.• This ensures that the total knee implant knee components
are positioned perfectly in the correct alignment. • Surgeon focusses his eyes in the operating field itself and
not away from the field.• It thus saves time.
Advantages
• No additional incisions in the leg or thigh in contrast to computer assisted surgery.
• As the intra medullary canal of the femur is not drilled, there is less blood loss post operatively.
• No waiting time for instruments to come from abroad unlike Patient specific instruments.
What does it differ from? 2) Patient specific instruments ( PSI)1) Computer navigation
( CAS)
How does it differ from computer navigation?
• The sensors are attached to the leg on the operating table as shown here.
• The position of the cuts is shown on the monitor in the background.
• Thus the surgeon has to shift his gaze from the leg to the monitor and back repetitively.
How does it differ from Patient specific cutting instruments?
• Scans done 6 weeks before surgery.
• Pictures are sent to the laboratory abroad
• 6 weeks waiting period for design, manufacture and supply of patient specific cutting blocks from abroad.
Patient specific cutting blocks placed on bone
Which patients benefit
All age groups of patients benefit particularly • Young patients undergoing
knee replacement for any reasons like injury, obesity, rheumatoid arthritis etc.
Young patient had Computer assisted knee replacement in 2008
Which patients benefit?• Young patients with bad
accidents and deformed bones. • In these patients, other
methods like computer assisted surgery & patient specific instruments can’t be used for technical reasons.
• It can be used in severe deformities and bone loss, unlike the other modalities like Patient specific instruments and computer navigation.
Which patients benefit?
• Middle aged patients with severe knee arthritis requiring a total knee replacement
• Perfect alignment increases durability of knee implant
Older patients also benefit
• Even experienced surgeons make errors while aligning components of a total knee arthroplasty.
• Neutral alignment is the goal but this is not always achieved.
• There is a correlation between perfect alignment and longevity of the implant.
• Normal life of a knee is 15- 20 years. • With advanced techniques like the I-Assist, the
life can be extended up to 35 years.
How patients benefit ?
• Tailor made perfect alignment.• No waiting time• Perfect alignment contributes to increased
longevity of the implant.• When I Assist is used in conjunction with
durable materials, life of a knee replacement can be extended up to 35 years.
Surgeons benefit
• Surgeons benefit as they save time during surgery by avoiding back and forth eye movements.
• Reduced operating time decreases risk of infection.
Hospital benefits
• No capital investment on imaging systems like special MRI
• No investment on Computer navigation system which costs about 1 crore.
I Assist
• Gives perfect alignment during surgery itself.
• Alignment along with durable materials like Zirconium and Cross linked polyetheylene increase of a knee replacement to 35 years.
• No need for future revision surgery in young patients.
