I have to start by saying that I have never had any issues with the ASR devise at all. I was very surprised about 6 months ago when the issue of ASR withdrawal first surfaced.
There is no doubt that the safety margin for the ASR is lower than other resurfacing systems like the BHR due to a 'low arc of cover'- described by Dr. Desmet. This is because the rim of the cup has become 'non -articular' to accommodate the cup holder.
Hence the failure rate is higher than the BHR.
The cups coming loose is certainly not true as I have implanted ASR cups in the most complex of cases. I am 100% confident that it is a technical issue.
It has proven to be an excellent tool in my hands and in dysplasia patients ( CROWE 3)- the s-rom with a ASR cup combination that is hard to beat.
The ASR reamers are very poor and not matched to the ASR cups. I have routinely used BHR or equivalent reamers for the ASR cups for 3 yrs since the time noticed the mismatch between the reamers and cup size for the ASR
The ASR has been excellent tool to provide an anatomical metal on metal articulation in small patients. I am very confident that it will work well if installed correctly. I will surely miss the ASR cup for small made patients if it is withdrawn completely.
with best regards
vijay bose
chennai
Saturday, March 13. 2010
Dr. Bose Discusses the ASR Withdrawal
Posted by Patricia Walter
in Doctor Information, Dr. Bose, HR Devices, HR Issues
at
14:57
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Tuesday, February 23. 2010
Dr. Bose Discusses Computer Navigation in Hip Resurfacing
Using computer navigation in joint surgery is a double
edged weapon. While potentially it can reduce the number of
outliers, it can also cause tremendous deviations and
absurd placements which would never be done with
conventional jigs. I have seen many examples of this done
elsewhere and referred to me for revision surgery.
Generally the input to the computer is made by a technique known as bone morphing where the surgeon uses pointer probes to point out the various bony landmarks to the computer. If the surgeon makes an error in this step then it obviously carries on in all further steps leading to a faulty placement. To argue that it removes human error is most irrational.
We have the brainlab navigation ( market leader in navigation) in our unit since 2007 and I did a series of cases at that time ( about 80 cases) . I have to say that the femoral cap placement was inferior to my placement with traditional jigs. However I found it useful when one had distorted anatomy as in previous prox. femoral osteotomy. I still use it for such cases.
There are many reasons in my opinion by which the conventional jig is far superior to the navigation in hip resurfacing.
1. bone morphing with the pointer probes damages the neck capsule which I protect passionately during hip resurfacing surgery and which I am sure is one of the key elements for my success rate.
2. I use navigation routinely during my Total knee replacements as the aim of the TKR surgery is to allign the components to the hip and ankle which are not visible in the surgical wound. In contrast in hip surgery the goal is not to align hip component to the spine , pelvis or knee/ ankle. The aim is to align components to local landmarks in the surgical wound, the location of which is given to the computer by the surgeon. Then the computer gives back the same information which the surgeon offered in the first place. ( this is unlike the TKR where the computer picks up the hip on merely moving the hip and not morphing). Arguments that the computer increases accuracy in hip surgery is frankly absurd and have to be dismissed as marketing techniques.
3. The concept of incorporating the combined anterversion is now the key in operating on FAI ( Femoro- acetabular impingement) which is the pathology in over 95 % of male patients having primary osteoarthritis. This is a dynamic assessment and can be done only with a jig using a lat cortex pin and cannot be done with navigation.
Having said all of the above one must make a distinction between what Prof. Cobb uses and what others use.
Prof . Cobb is the only one to my knowledge who uses a CT based navigation. The CT gives information which the surgeon cannot access unlike imageless navigation with all other surgeons which depends on surgeon's input based on bone morphing that defeats the whole purpose of navigation.
In conclusion I would like to say that imageless navigation has very limited role in hip arthroplasty ( eg previosely operated cases) and is an excellent tool in Knee arthroplasty.
CT based navigation for hips which is still not available commercially ( which prof. Cobb uses) may have a significant role in hip arthroplasty. This has to be balanced with the radiation dose for routine CT to be applied universally( approx 30 -50 conventional x-ray dose )
wishing you the very best
with best regards
vijay bose
chennai
Generally the input to the computer is made by a technique known as bone morphing where the surgeon uses pointer probes to point out the various bony landmarks to the computer. If the surgeon makes an error in this step then it obviously carries on in all further steps leading to a faulty placement. To argue that it removes human error is most irrational.
We have the brainlab navigation ( market leader in navigation) in our unit since 2007 and I did a series of cases at that time ( about 80 cases) . I have to say that the femoral cap placement was inferior to my placement with traditional jigs. However I found it useful when one had distorted anatomy as in previous prox. femoral osteotomy. I still use it for such cases.
There are many reasons in my opinion by which the conventional jig is far superior to the navigation in hip resurfacing.
1. bone morphing with the pointer probes damages the neck capsule which I protect passionately during hip resurfacing surgery and which I am sure is one of the key elements for my success rate.
2. I use navigation routinely during my Total knee replacements as the aim of the TKR surgery is to allign the components to the hip and ankle which are not visible in the surgical wound. In contrast in hip surgery the goal is not to align hip component to the spine , pelvis or knee/ ankle. The aim is to align components to local landmarks in the surgical wound, the location of which is given to the computer by the surgeon. Then the computer gives back the same information which the surgeon offered in the first place. ( this is unlike the TKR where the computer picks up the hip on merely moving the hip and not morphing). Arguments that the computer increases accuracy in hip surgery is frankly absurd and have to be dismissed as marketing techniques.
3. The concept of incorporating the combined anterversion is now the key in operating on FAI ( Femoro- acetabular impingement) which is the pathology in over 95 % of male patients having primary osteoarthritis. This is a dynamic assessment and can be done only with a jig using a lat cortex pin and cannot be done with navigation.
Having said all of the above one must make a distinction between what Prof. Cobb uses and what others use.
Prof . Cobb is the only one to my knowledge who uses a CT based navigation. The CT gives information which the surgeon cannot access unlike imageless navigation with all other surgeons which depends on surgeon's input based on bone morphing that defeats the whole purpose of navigation.
In conclusion I would like to say that imageless navigation has very limited role in hip arthroplasty ( eg previosely operated cases) and is an excellent tool in Knee arthroplasty.
CT based navigation for hips which is still not available commercially ( which prof. Cobb uses) may have a significant role in hip arthroplasty. This has to be balanced with the radiation dose for routine CT to be applied universally( approx 30 -50 conventional x-ray dose )
wishing you the very best
with best regards
vijay bose
chennai
Posted by Patricia Walter
in Approaches to Surgery, Dr. Bose, General Information, HR Issues
at
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Thursday, January 21. 2010
Stuart's Hip Resurfacing Dr. Bose 2009
>Nov. 1, 2009
I sit in Chennai 4 days post op on my right hip, Birmingham w/ Dr. Bose. Today when I seem to have gotten past the pain bits and am actually looking at my gait.
>Nov. 15, 2009
I sit in Chennai 4 days post op on my right hip, Birmingham w/ Dr. Bose. Today when I seem to have gotten past the pain bits and am actually looking at my gait.
>Nov. 15, 2009
I am breaking my return trip from Chennai in Munich for 6 days (enjoying
German beer, bread and brats!). 18 days post op and did an easy 2-hour bike
around the city's parks today. Leg still a bit long but coming around.
Thanks for your work on the website and support!
cheerz,
stuart
Posted by Patricia Walter
in Dr. Bose, Personal HR Stories 2009
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(Page 1 of 1, totaling 3 entries)


