Chondrocyte Implants

[toby19]

Hi all,

Just wanted to find out if anyone knows much about chondrocyte implants. How effective are they? Is this procedure currently under investigation? How much does the procedure cost approximately?

Thanks in advance.

[bloss]

Hi Toby,
There is an Orthopaedic Surgeon in Chatswood, Sydney who is doing this procedure http://www.sydneyortho.com.au/drparker.html

The procedure, material and the "cloning" has recently been given Medicare and health fund cover.



Hi all,

Just wanted to find out if anyone knows much about chondrocyte implants. How effective are they? Is this procedure currently under investigation? How much does the procedure cost approximately?

Thanks in advance.

[injuryupdate]

There still isn't a lot of evidence suggesting that it does any better than microfracture (which is a surgical technique of drilling some holes into the exposed bone).

It is good for the patients who wish to undergo the procedure that Medicare is now providing rebates, if this is the case.

However, I would suggest that it is fairly typical of the Medicare system. If a new non-surgical method of treatment arises and gains widespread acceptance (e.g. Synvisc injections for knee O/A, shock wave therapy for calcific tendinopathy) then Medicare will refuse to recognise the therapy (on the grounds that 'not enough evidence has been published which proves the treatment works'). However, when a new surgical treatment appears on the horizon, Medicare benefits will magically appear based on the premise that surgeons are god-like beings who must be helping the patients at all times whenever they operate.

I watched the Australian Story on Dr Death's accuser on Monday night on ABC and it goes to show how a surgeon can get to the point of literally murdering patients (which is what Dr Death is accused of, that is knowlingly and intentionely doing bad operations on patients which result in their death) and for almost the entire time this was going on, he was being held up on a pedestal by the hospital adminstrators. Apparently the funding of the hospital was partially based on points for how much difficult surgeries that were being performed and Dr Death (Patel) was breaking records for points by taking on heaps on ridiculously tough cases (some of which were complications of his earlier less tough cases). Sorry this has deviated from the original post - the point is that new and so-called advanced surgeries are not always better than the alternatives. Chondral grafting is still definitely in the jury-is-still-out category.

[injuryupdate]

Thanks pcfu for that summary. I think you put the case forwards very well. Obviously if you are young and given the information that nothing else is going to get you back to sport again, it is definitely worth a try (if you can afford it). Chondrocyte implants are definitely no worse than the alternative (which is microfracture/osteoplasty) and the theory is better. They are a long way obviously from giving you a perfectly normal knee joint though. Many of the so-called excellent results may be because those who have been through the process eventually give up on the activity that was overloading the joint in the first place (e.g. playing football).

[injuryupdate]

An excellent study just released in the CJSM in July 2005 edition, abstract and intro section reproduced below. Was a randomised trial. Almost half the patients were improved by a simple debridement (arthroscopy) and 6 months of rest/recovery. Of the patients who weren't improved, half were randomised for chondrocyte implants and half had an autograft from inside the knee (mosaicplasty). The mosaicplasty group did at least as well as the ACI group.

Obviously ACI still has a potential place for failed results but it is hard to justify as standard therapy for chondral lesions when far simpler and much cheaper procedures appear to do just as well (or badly, depending on whether you are an optimist or pessimist!):

Clinical Journal of Sport Medicine: Volume 15(4) July 2005 pp 220-226
Comparative Evaluation of Autologous Chondrocyte Implantation and Mosaicplasty: A Multicentered Randomized Clinical Trial
Dozin, Beatrice PhD*; Malpeli, Mara PhD*; Cancedda, Ranieri MD*†; Bruzzi, Paolo MD‡; Calcagno, Silvano MD§; Molfetta, Luigi MD§∥; Priano, Ferdinando MD§∥; Kon, Elisaveta MD¶; Marcacci, Maurilio MD¶

From *Medicina Rigenerativa, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy; †Dipartimento di Oncologia, Biologia e Genetica, Università di Genova, Genova, Italy; ‡Epidemiologia Clinica, Istituto Nazionale per la Ricerca sul Cancro, Genova, Italy; §Clinica Ortopedica, Ospedali S. Martino, Genova, Italy; ∥Dipartimento di Scienze Motorie, Università di Genova, Genova, Italy; and ¶Laboratorio di Biomeccanica, Istituti Ortopedici Rizzoli, Bologna, Italy.

Received for publication July 2004; accepted May 2005.

Supported by the Italian Ministry of Health.

Reprints: Beatrice Dozin, PhD, Laboratorio di Medicina Rigenerativa, Istituto Nazionale per la Ricerca sul Cancro Largo Rosanna Benzi, n°10, 16132 Genova, Italy (e-mail: beatrice.dozin@istge.it).

Abstract TOP
Objective: To compare the respective performance and effectiveness of autologous chondrocyte implantation (ACI) and mosaicplasty at resurfacing local full-thickness chondral defects of the knee.

Design: Randomized clinical trial.

Setting: Multicenter trial at orthopedic clinics and university hospitals conducted from 1997 to 2000.

Patients: A population of patients selected according to eligibility criteria of age, traumatic origin of the defect, its localization, size, and gravity, and above all, no previous surgical treatment of the lesion. Forty-seven patients were randomly assigned to ACI or mosaicplasty and subjected to arthroscopic debridement of the lesion at the time of enrollment. They were called for surgery 6 months after the initial debridement.

Main Outcome: Improved knee functionality as assessed by repeated clinical evaluation based on the International Knee Documentation Committee Scale and the Lysholm Knee Scoring Scale.

Results: Fourteen patients (31.8%) experienced substantial improvement following the initial debridement and, being clinically cured, received no further treatment. Seven patients (15.9%) were lost to follow-up. Among the 23 patients (52.3%) who could effectively be evaluated, a complete recovery (ie, Lysholm Knee Scoring Scale score, 90-100) was observed upon clinical examination in 88% of the mosaicplasty-treated patients and in 68% of the ACI-treated ones (P = 0.093).

Conclusions: Although the low power of our study prevents definitive conclusions, ACI and mosaicplasty are cartilage repair techniques that are clinically equivalent and similar in performance. The high percentage of spontaneous improvement (⅓ of the patients) observed after simple debridement calls into question the need for prompt surgical treatment of patients with lesions similar to those included in this clinical trial. Moreover, this finding warrants further investigation, ideally through randomized clinical trials in which patients subjected to debridement alone are compared with patients undergoing reconstructive surgery.

Damage to articular cartilage is a major challenge for the orthopedic community due to the limited self-renewal capacity of this tissue. Lack of vascularization and of penetration by lymphatic vessels1 severely limits healing of cartilage defects that are superficial to the subchondral plate. These lesions do not repair spontaneously and are analogous to those observed during the early phase of osteoarthritis.2,3 Deeper lesions penetrating the vascularized subchondral bone are repaired to some extent as mesenchymal chondroprogenitor stem cells invade the lesion, differentiate into chondrocytes, and form cartilage.4 However, the repair is only transient: the tissue is fibrous in nature and does not have the functional properties of native hyaline cartilage, thus making it more vulnerable to the action of free radicals, metalloproteinases, and catabolic cytokines.5,6 Sustained damage of the joint and matrix breakdown quite often lead to clefts and fissures on the articular surface and to the onset of degenerative joint diseases such as osteoarthritis.7-11

Full-thickness chondral lesions of the knee, which can be osteochondritis desiccans, fracture, or chondromalacia, are particularly problematic in young individuals and athletes, because not all the joint treatments available today are suitable for them. For instance, total knee replacement that can be performed in severely injured and disabled elderly people is not advisable for younger patients with similar joint dysfunction due to the limited lifetime of the prostheses.12,13

In a retrospective review of 31,516 knee arthroscopies, 63% revealed cartilage lesions. Among these, 19.2% were grade IV Outerbridge. In 5% of all arthroscopies, a grade IV chondral lesion was found in young patients under the age of 40. In addition, only 36% of the patients did not present ligament and/or meniscus lesions concomitant with the chondral injury.14

Many surgical options have been proposed to treat focal traumatic lesions of both chondral and osteochondral types.15-18 These include methods aimed at (a) stimulating the formation of new cartilaginous tissue by facilitating access to the vascular system and bringing new progenitor cells capable of chondrogenesis (reparative techniques such as arthroscopic subchondral drilling, microfractures, or chondroabrasion),19-22 and (b) reconstructing the defect with autologous, homologous, or other tissue (reconstructive techniques). Various materials such as allografts, autografts, synthetic polymers, and periosteal and perichondral flaps have been proposed,23-31 but the 2 techniques that have gained widespread interest over the last decade are autologous chondrocyte implantation (ACI) and mosaicplasty.

Autologous chondrocyte implantation, a biologic approach introduced in Sweden in 1987,32 is based on the transplantation, beneath a tightly sealed periosteal flap, of a suspension of autologous articular chondrocytes previously cultured and expanded in vitro. This method is interesting because it allows the treatment of large defects without donor site morbidity; however, it is an expensive, 2-stage procedure, and the maturation of the implanted cells into cartilage can be a rather long process.

Various uses of autografts for osteochondral defect reconstruction have been put forward. An autologous osteochondral graft can be applied by arthroscopy or open knee surgery, depending on the size of the articular defect.33 Osteochondral grafting was initially proposed by Matsusue et al34 and Bobic,35 who retrieved the grafts from the intercondylar notch. In 1997, Hangody et al36 described the technique of mosaicplasty, whereby multiple small cylindrical osteochondral plugs are harvested from a nonweight-bearing area of the distal femoral articular surface and then placed in the debrided defect.

Independent clinical studies have shown that both ACI and mosaicplasty may hold particular promise as cartilage repair strategies. Although long-term clinical results on the durability of the 2 procedures are not yet available, both seem to achieve better articular repair than more traditional surgical techniques. When applied to patients presenting with femoral condyle, patellar, and/or trochlear lesions, ACI and mosaicplasty are successful in 60% to 65% and 90% to 95% of cases, respectively. This variability in the clinical outcome depends in part on the localization of the lesions. Good to excellent results are seen in patients presenting isolated femoral condyle lesions or osteochondritis desiccans. Results obtained in the case of multiple lesions, patellar injury, or femoral condyle lesion associated with anterior cruciate ligament injury usually yield less encouraging outcomes.37-40 Nevertheless, these rates have emerged from uncontrolled medium/long-term studies performed on nonhomogenous groups of subjects and thus cannot be comparatively evaluated. The aim of the present study was to assess the true comparative effectiveness of the 2 techniques through a randomized clinical trial involving patients meeting selective eligibility criteria.

[Unregistered]

Hi,
I have recently had this precedure in my right knee to treat an OCD. Before this they attempted to screw the OCD back into place which didnt work. I was struggling to walk up stairs and at only 19yrs of age that caused a problem. Its been 10mths since the op and my knee feels great. They recommend a slow recovery of 12mths or more before i start to run at the moment im jogging on a trampoline with no pain and walking up 2 stairs at a time pain free. I can walk and ride a bike 100% pain free. I think the procedure is well worth the chance. You can contact me further at snotgravy@hotmail.com if you require some more info.
Regards Scott



Hi all,

Just wanted to find out if anyone knows much about chondrocyte implants. How effective are they? Is this procedure currently under investigation? How much does the procedure cost approximately?

Thanks in advance.

[Luke]

Good to hear Scott. I recently had my knee done 7 weeks ago. I was well aware of the stats regarding failed grafts and the lack of evidence. Like you though, I was too young to have my knee stopping me the way it was. I'm glad you have done well. Now I just have to see what happens to me with time. The frustrating thing is the conservative rehab, I feel like I could push it alot more but I'm simply not allowed to because of the rehab protocols.

[Unregistered]

Gday Guys,

I have had this surgery twice- I am 15 months post 1 implant (MFC) and 2 and a bit yrs post the first two implants (Patella & Troch). I am also young like you guys, 23. If I could say one thing Luke it would be to not rush things even though it feels good, just look after the implant and focus on regaining the strenght back in the leg. I've found that whilst it feels good at 12 months, it'll still be from 18-24 months untill it really starts to kinda feel normal again. And yes it's a pain in the arse to go slow and take it easy, but you don't want to have to go back to sqaure one again and start all over again.

Good Luck.