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Offline bsonday

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Knutsen study
« on: May 02, 2008, 09:51:11 PM »
How does everyone feel about the Gunnar Knutsen study, which basically concluded that microfracture and ACI yield very similar results after two years (a disappointment).  Microfracture is not even an option for my patellar lesion, but the results of this study concern me because I was really hoping for some fresh hyaline cartilage down the road :)...

Enjoy your weekends.

Best,
Ben
Removal of loose bodies (cartilage pieces)--7/2/2007
Lots of rehab (quad strengthening) which didn't help much
Biopsy for ACI, 1.5cm x 1.5cm patellar cartilage lesion found--5/7/2008
Patellar ACI with Fulkerson, slight lateral release (to get under the patella)--7/2/2008
Happiness--Early 2010?

Offline MegTX

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Re: Knutsen study
« Reply #1 on: May 02, 2008, 10:11:16 PM »
2 years out doesn't concern me.  5-7 years out, and longer, that concerns me.

Microfracture and ACI have almost the same rehab/healing time (microfracture may be a bit shorter, but you're still looking at basically a year out of commission.)  BUT, for that LOOOONG rehab/healing time, you only gain a few years on microfracture, ESPECIALLY for the patella which is subject to harsher shear forces than other areas of the knee.  ACI results in a different type of cartilage repair, which means longer lasting repair, we're talking 20+ years and possibly a lifetime if they correct the underlying problem and you take care of the new cartilage.

There's so much to consider with all of these treatments, I don't look at just one aspect, or even one report/study.

So there's my spare change.  :-)
Lateral Release, Medial "Reef" - '91
{16 years of grinding, pain, swelling and lots of ice}
'scope 7/07 - .7cm2 tibial plateau microfracture, 2.5cm2 grade4 patellar CP debridement
ACI & Fulkerson TTT 2/08 (patella lesion then 4.5cmx3cm)

jonhark

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Re: Knutsen study
« Reply #2 on: May 03, 2008, 12:24:13 AM »
ACI doesn't always result in 100% hyaline cartilage. But, I must say, I've had both procedures done in the past year and a half. The Microfracture was done with my TTT for my first surgery in Jan 07. It failed miserably. I'm 8 and a half months out from ACI and the difference is dramatic. It is a long haul though. I haven't had a miraculous recovery. Expect some improvement from pre-op by 6 months. In fact, you will likely notice a big difference in the daily throbbing pain. By 9-12 months your cells should be done proliferating. The cartilage will continue to harden/mature from 12-24 months.

My suggestion, if you go forward with the surgery is 1) get it done as soon as possible 2) Plan on at a minimum 12 months and a maximum of 24 months of restricted living. The more you stay off it and avoid long periods of bent legs and standing; the better you'll feel and the quicker you'll recover.

The recovery/rehab is a rollercoaster ride and isn't a linear recovery.  I have noticed a big difference in stairs, and the ability to exercise.

I had an MRI at 7 months and it showed no delamination, flaps or overgrowth and good margins of the cartilage graft. This surgery works--you just have to foster the right environment for it to grow and develop.

There is no reason to believe this isn't a long-term fix for you defect. As long as you don't load the knee too much.

Offline djs60

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Re: Knutsen study
« Reply #3 on: May 03, 2008, 02:50:52 PM »
bsonday,

Can you point me to this study?  I'd be interested in reading it.

Do you have a link to it, or the citation?

thanks,
djs60
3/06 left knee arthroscopy - grade IV lateral trochlea defect
chondroplasy & removal of loose bodies
1/07 left knee arthroscopy/cartilage biopsy
4/27/07 left knee trochlea & patella ACI with TTO

Offline bsonday

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Re: Knutsen study
« Reply #4 on: May 03, 2008, 03:35:45 PM »
Autologous Chondrocyte Implantation Compared with Microfracture in the Knee
A Randomized Trial

The Journal of Bone and Joint Surgery (American) 86:455-464 (2004)

If you can't access the paper online (sometimes you have to pay), give me your email address and I'll send you the copy that I have.
Removal of loose bodies (cartilage pieces)--7/2/2007
Lots of rehab (quad strengthening) which didn't help much
Biopsy for ACI, 1.5cm x 1.5cm patellar cartilage lesion found--5/7/2008
Patellar ACI with Fulkerson, slight lateral release (to get under the patella)--7/2/2008
Happiness--Early 2010?

Offline djs60

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Re: Knutsen study
« Reply #5 on: May 05, 2008, 12:31:00 AM »
thanks - I was able to get the full text.

djs60
3/06 left knee arthroscopy - grade IV lateral trochlea defect
chondroplasy & removal of loose bodies
1/07 left knee arthroscopy/cartilage biopsy
4/27/07 left knee trochlea & patella ACI with TTO

Offline bsonday

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Re: Knutsen study
« Reply #6 on: May 05, 2008, 04:33:48 AM »
Let me know what you think after you read it, if you get a chance.

Best,
Ben
Removal of loose bodies (cartilage pieces)--7/2/2007
Lots of rehab (quad strengthening) which didn't help much
Biopsy for ACI, 1.5cm x 1.5cm patellar cartilage lesion found--5/7/2008
Patellar ACI with Fulkerson, slight lateral release (to get under the patella)--7/2/2008
Happiness--Early 2010?

Offline John1

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Re: Knutsen study
« Reply #7 on: May 09, 2008, 12:18:58 PM »
I read this study a few years ago. I'm sure I pointed out the results on here before. I think the problem with microfracture is most doctors and patients don't follow the correct procedure and rehab as outlined by Dr. Steadman. It seems like they don't understand the reasoning why it is important.

I believe it was this paper or another I read that found that microfracture was worse than ACI in older people or for larger defects (> 4 cm^2). Are than any newer studies on ACI?
4/12/05 Arthroscopy: plica removal and medial femoral condyle microfracture (2 cm^2)
11/9/05 Arthroscopy: complete removal of plica, removal of scar tissue on fat pad behind patella tendon and on medial side.

Offline Dave1

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Re: Knutsen study
« Reply #8 on: May 10, 2008, 01:28:19 PM »
The 5 year results are out on this.  9 failures out of 40 for both the ACI and Microfracture so NO real definite conclusions as to the best form of treatment.

Not quite 'like for like' or 'apples for apples' in that the ACI patients had an average age 33 with defect size 5.1cm2  and 1.6 previous operations.
Microfracture patients had an average age 31 with defect size 4.5cm2  and 1.4 previous operations.
Younger patients performed better.

Another interesting point was that there were NO failures in the 10 patients who had hyaline like cartilage.  ACI outperformed microfracture in the quality of cartilage and I suspect will perform better than microfracture in the 10 year review.  ACI treatment has also improved since this study and will  improve in the years ahead.  Note the group of patients in this study were operated from 1999-2000. 
 

Offline djs60

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Re: Knutsen study
« Reply #9 on: May 10, 2008, 04:09:04 PM »
Dave,

Do you have a citation for the 5 year update?

I read this the other day, and found it very interesting.

It is a well done randomized trial, which is actually pretty unusual in the surgical literature.

I was surprised by the lack of difference in cartilage quality in the 2 year data.  However, there is a potential methodological flaw in the study.  It would have been better if they had two experts independently grade the cartilage quality (so the reader could get a sense of how much agreement there was), but it appears the 2 experts decided by consensus how to grade the samples.  This _could_ have resulted in random misclassification, and obscured a true difference.

Anyway, I'd be interested in looking at the newer data.

thanks,
Dan
3/06 left knee arthroscopy - grade IV lateral trochlea defect
chondroplasy & removal of loose bodies
1/07 left knee arthroscopy/cartilage biopsy
4/27/07 left knee trochlea & patella ACI with TTO

Offline David3

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Re: Knutsen study
« Reply #10 on: May 10, 2008, 04:10:19 PM »
Interesting Dave. I have the original paper, but do you have a link or reference to where these 5-year follow-up results are published? I'd be interested in following up on this with my OS.

Also, you imply that results may be better for ACI now ("ACI has improved since this study .... from 1999-2000"). For all of us going through ACI now, we obviously hope that the probability of failure is less than the 9/40 found in this 5-year follow-up study. However, are there any definite improvements that people are aware of that have increased the chance of success and/or longevity of ACI operations today relative to those done in 1999-2000?  Or are we just hoping...?

David
2006: Left Knee (LK) microfracture (MFC, LFC, Trochlear), failed at 6 months
7/07: ACI/TTO of LK (MFC, LFC, trochlea, patella)
2014: Considering ACI treatment on RK.

Offline MegTX

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Re: Knutsen study
« Reply #11 on: May 10, 2008, 08:40:51 PM »
I'd also like to note that I've read in several places that the ACI can look like it has formed fibrocartilage early on (the first year or two) or a mix of fibro and hyaline, but through some process, at later checks it shows hyaline.  I also expect the longer-term studies to show much better results for ACI than microfracture.
Lateral Release, Medial "Reef" - '91
{16 years of grinding, pain, swelling and lots of ice}
'scope 7/07 - .7cm2 tibial plateau microfracture, 2.5cm2 grade4 patellar CP debridement
ACI & Fulkerson TTT 2/08 (patella lesion then 4.5cmx3cm)

Offline bsonday

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Re: Knutsen study
« Reply #12 on: May 11, 2008, 07:47:02 PM »
Hey MegTX,

I would love to read that study in regards to ACI about how it can go from fibrocartialge to hyaline later on.  Do you know where I could find that?

Best,
Ben
Removal of loose bodies (cartilage pieces)--7/2/2007
Lots of rehab (quad strengthening) which didn't help much
Biopsy for ACI, 1.5cm x 1.5cm patellar cartilage lesion found--5/7/2008
Patellar ACI with Fulkerson, slight lateral release (to get under the patella)--7/2/2008
Happiness--Early 2010?

Offline MegTX

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Re: Knutsen study
« Reply #13 on: May 11, 2008, 09:15:32 PM »
I'll try to find the study, but I don't know for sure where I found it.  I read so many abstracts and texts of articles and study results when I was fighting the appeals, that I couldn't begin to list everything I read.   :o 

I'm don't think that the fibrocartilage actually turned into hyaline cartilage.  My understanding of biology and cell matrices doesn't support that theory.  What I suspect, though they were only reporting findings, they didn't speculate as to HOW it happened, is that there was initially a fibrocartilage formation, and then hyaline formed under it.  Then when the first checks were done, the fibrocartilage is what was apparent, but as it wore away the hyaline cartilage was exposed.  That is purely my layman's speculation, however, based on a bit of medical and physiological background.
Lateral Release, Medial "Reef" - '91
{16 years of grinding, pain, swelling and lots of ice}
'scope 7/07 - .7cm2 tibial plateau microfracture, 2.5cm2 grade4 patellar CP debridement
ACI & Fulkerson TTT 2/08 (patella lesion then 4.5cmx3cm)

Offline bsonday

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Re: Knutsen study
« Reply #14 on: June 09, 2008, 06:20:25 AM »
In case anyone is still curious, I found some more interesting stuff which is pretty optimistic along the lines of what MegTX told us.  Basically, cartilage can continue to mature from fibrocartilage-like stuff to hyaline, and when it does the knee keeps getting better and better:

http://proceedings.jbjs.org.uk/cgi/content/abstract/88-B/SUPP_I/114

"Results: At 1 year, hyaline repair tissue was found in 48 (53%) ACI-C grafts, 7 (44%) ACI-P grafts, and 12 (36%) MACI grafts. The frequency of hyaline tissue found in biopsies performed at 2 years (84%) was significantly higher than those performed at 1 year (48.6%), p=0.0001, suggesting that grafts continue to remodel after the first year post implantation.

Clinical outcomes during the first two postoperative years did not vary according to repair morphology type, though hyaline repair was associated with better clinical outcomes beyond 2 years; At 1 year, good to excellent clinical scores were observed in 29 (78.4%) patients with hyaline-like repair, 23 (76.7%) patients with fibrohyaline repair, and 54 (74.0%) patients with fibrocartilage repair. By years 3 and 4 post-implantation, clinical scores further improved in patients with hyaline-like repair yet declined in those with fibrocartilage and fibrohyaline. The difference was significant at 3 years though not at 4 due to the small number of cases.

Conclusions: Achieving hyaline-like repair is critical to the longevity of cartilage repair. The finding of hyaline-like cartilage or fibrohyaline cartilage in 31 of 37 biopsies (84%) performed after 2 years is therefore encouraging and supports further use of the ACI technique."

Thoughts?
Removal of loose bodies (cartilage pieces)--7/2/2007
Lots of rehab (quad strengthening) which didn't help much
Biopsy for ACI, 1.5cm x 1.5cm patellar cartilage lesion found--5/7/2008
Patellar ACI with Fulkerson, slight lateral release (to get under the patella)--7/2/2008
Happiness--Early 2010?