Research progress of rehabilitation after autologous chondrocyte implantation on knee / 中国修复重建外科杂志

Objective: To summarize the research progress of rehabilitation after autologous chondrocyte implantation (ACI). Methods: The literature related to basic science and clinical practice about rehabilitation after ACI in recent years was searched, selected, and analyzed. Results: Based on the included literature, the progress of the graft maturation consists of proliferation phase (0-6 weeks), transition phase (6-12 weeks), remodeling phase (12-26 weeks), and maturation phase (26 weeks-2 years). To achieve early protection, stimulate the maturation, and promote the graft-bone integrity, rehabilitation protocol ought to be based on the biomechanical properties at different phases. Weight-bearing program, range of motion (ROM), and options or facilities of exercise are importance when considering a rehabilitation program. Conclusion: It has been proved that the patients need a program with an increasingly progressive weight-bearing and ROM in principles of rehabilitation after ACI. Specific facilities can be taken at a certain phase. Evidences extracted in the present work are rather low and the high-quality and controlled trials still need to improve the rehabilitation protocol.

Repair of Partial Thickness Cartilage Defects Using Cartilage Extracellular Matrix Membrane-Based Chondrocyte Delivery System in Human Ex Vivo Model

Treatment options for partial thickness cartilage defects are limited. The purpose of this study was to evaluate the efficacy of the chondrocyte-seeded cartilage extracellular matrix membrane in repairing partial thickness cartilage defects. First, the potential of the membrane as an effective cell carrier was investigated. Secondly, we have applied the chondrocyte-seeded membrane in an ex vivo, partial thickness defect model to analyze its repair potential. After culture of chondrocytes on the membrane in vitro, cell viability assay, cell seeding yield calculation and cell transfer assay were done. Cell carrying ability of the membrane was also tested by seeding different densities of cells. Partial defects were created on human cartilage tissue explants. Cell-seeded membranes were applied using a modified autologous chondrocyte implantation technique on the defects and implanted subcutaneously in nude mice for 2 and 4 weeks. In vitro data showed cell viability and seeding yield comparable to standard culture dishes. Time dependent cell transfer from the membrane was observed. Membranes supported various densities of cells. Ex vivo data showed hyaline-like cartilage tissue repair, integrated on the defect by 4 weeks. Overall, chondrocyte-seeded cartilage extracellular membranes may be an effective and feasible treatment strategy for the repair of partial thickness cartilage defects.

Autologous Chondrocyte Implantation as a Secondary Procedure after Failed Microfracture for Osteochondral Lesion of Talus / 대한족부족관절학회지

Microfracture as a reparative strategy is the treatment of choice for an osteochondral lesion of talus. Although the results of microfracture are generally excellent, at least 30% of patients who received microfracture have acute or chronic ankle pain with several or unknown causes. The most important factor for unsatisfactory outcome after microfracture is the size of the lesion. For failed osteochondral lesion of talus, the second options are autologous osteochondral graft, autologous chondrocyte implantation, or re-microfracture. In this article, we present the autologous chondrocyte implantation as a second procedure for failed microfracture and compare its clinical outcome with other methods based on a literature review.

Platelet rich plasma associated with heterologous fresh and thawed chondrocytes on osteochondral lesions of rabbits / Associação de plasma rico em plaquetas e condrócitos heterólogos frescos e descongelados em lesão osteocondral de coelhos

Chondrocytes obtained from stifle joint of New Zealand White rabbits were cultivated. Half of cells were maintained in culture for later implantation and the others frozen during six months to evaluate viability. A circular osteochondral defect was created in the right stifle of other twenty seven rabbits. The control group (CG) received no treatment. The thawed (TH) and fresh (FH) heterologous groups received, respectively, an implant of cultivated thawed or fresh heterologous chondrocytes associated with platelet rich plasma (PRP). The CG group showed greatest pain and lameness compared to the other groups seven days after the implantation. Microscopically, at 45 and 90 days, the TH and FH groups showed filling with cartilaginous tissue containing chondrocytes surrounded by a dense matrix of glycosaminoglycans. In the CG group, healing occurred with vascularized fibrous connective tissue without integration to the subchondral bone. Cryopreserved heterologous chondrocytes were viable for implantation and healing of osteochondral lesions; the association with PRP allows the fixation of cells in the lesion and offers growth factors which accelerates repair with tissue similar to articular hyaline cartilage.

Cultivaram-se condrócitos obtidos da articulação do joelho de coelhos. Metade das células foi mantida em cultura para posterior implantação, e a outra metade foi congelada durante seis meses com a finalidade de avaliar a viabilidade. Criou-se um defeito circular osteocondral no joelho direito de outros vinte e sete coelhos. O grupo controle (GC) não recebeu tratamento. Os grupos descongelado (TH) e fresco (FH) receberam, respectivamente, implantes heterólogos de condrócitos cultivados descongelados e frescos, associados com PRP. O grupo GC apresentou maior dor e claudicação em comparação com os outros grupos aos sete dias após o implante. Microscopicamente, aos 45 e 90 dias, os grupos TH e FH mostraram preenchimento da falha com tecido cartilaginoso contendo condrócitos circundados por uma matriz densa de glicosaminoglicanos. Nesse período, no grupo CG, a cura ocorreu com tecido conjuntivo fibroso vascularizado e sem integração com o osso subcondral. Condrócitos heterólogos criopreservados foram viáveis para implantação e tratamento de lesões osteocondrais; a associação com o PRP permitiu a fixação de células na lesão e ofereceu fatores de crescimento que aceleraram a reparação com o tecido semelhante à cartilagem hialina articular.

Cell-based therapy for the treatment of focal articular cartilage lesions: a review of six years of studies in a Malaysian University Medical Centre

Autologous chondrocyte implantation (ACI) is a significant technique that has gained widespread use for the treatment of focal articular cartilage damage. Since its inception in 2004, the Tissue Engineering Group (TEG) of the Faculty of Medicine, University Malaya has been dedicated to carrying out extensive research on this cell-based therapy. The objective of this report, comprising one clinical case report, six animal studies and one laboratory study, is to summarise and discuss TEG’s key findings. On the whole, we observed that the ACI technique was effective in regenerating hyaline-like cartilage in treated defects. Autologous chondrocytes and mesenchymal stem cells (MSC) were found to produce comparable tissue repair irrespective of the state of MSC differentiation, and the use of alginate-based scaffolding and oral pharmacotherapy (Glucosamine and Chondroitin Sulphate) was shown to enhance ACI-led tissue repair. ACI is suggested to be an efficient therapeutic option for the treatment of articular cartilage defects of the knee.

Autologous chondrocyte implantation for knee focal cartilage defects: 3 years' follow-up at the University Malaya Medical Centre

Autologous chondrocyte implantation (ACI) is a widely accepted procedure for the treatment of large, fullthickness chondral defects involving various joints, but its use in developing countries is limited because of high cost and failure rates due to limited resources and support systems. Five patients (age <45 years) with focal cartilage defects received ACI at University of Malaya from 2006 to 2007 and followed up for 36 months. The average presubjective Knee Evaluation Forms (IKDC) improved from 38.44±6.29 to 25.6±8.04 postoperatively, the Oxford Knee Score (OKS) went from 25.6±8.04 to 13.96±1.63 and the American Knee Society Score (AKSS) improved from 80±14.33 to 92.96±5.82 post-operatively. Thus improvements were seen in the IKDC and AKSS score but not in the OKS. Magnetic resonance images showed the presence of cartilage tissue filling in the lateral and medial patellar facet and medial femoral condyle in three patients. Failures were seen in two patients, both with patellar defects and over the age of 36 years. Treatment with autologous chondrocyte implantation for focal cartilage defect in lateral and medial patellar facet and medial femoral condyle showed early improvement which was maintained at 3 yrs follow-up. ACI provided satisfactory outcome in focal cartilage defects involving the femoral condyle.

Bilateral Osteochondritis Dissecans of the Femoral Condyles in Both Knees: A Report of Two Sibling Cases

Osteochondritis dissecans (OCD) of both femoral condyles is very rare, with no previously reported cases of bilateral OCD of both knees in two siblings. We report on a brother and sister with both femoral condyle OCD with a description of surgical technique and clinical results. Fixation using headless compressive screws, osteochondral autologous transplantation and autologous chondrocyte implantation were all successful.

Autologous Chondrocyte Implantation for Articular Cartilage Defect of Femoral Condyle / 대한정형외과학회잡지

PURPOSE: To evaluate the midterm clinical and histological results after autologous chondrocyte implantation (ACI) for an articular cartilage defect of the distal femoral condyle. MATERIALS AND METHODS: Twenty four cases with an articular cartilage defect (Outerbridge grade IV) of the femoral condyle that was confirmed by MRI and the arthroscopic findings underwent ACI. Their mean age at the time of surgery was 42.8 years and the mean follow-up period was 53.2 months (range, 20-82 months). At the last follow up, the articular cartilage view (SPGR) of MRI was examined and the clinical results were evaluated using the HSS and Lysholm scores. In 8 cases, second-look arthroscopy and biopsy were performed and evaluated using histological and histochemical methods. RESULTS: All cases except for one showed well-regenerated articular cartilage on MRI. All cases showed significant clinical improvement in the HSS and Lysholm scores (p<0.0001), with the exception of the Lysholm score of an articular cartilage fracture. Histologically, the regenerated tissue appeared to be a hyaline-like cartilage in all specimens. CONCLUSION: ACI for the treatment of articular cartilage defects of the distal femoral condyle showed a good clinical and MRI results. In OA, the clinical results were relatively acceptable after an associated high tibial valgus osteotomy. However, a longer term follow-up study will be needed to reach a final conclusion.

Autologous Chondrocyte Implantation for Treating Chondral Defects of the Femoral Condyle

PURPOSE: We wanted to evaluate the clinical and objective results of autologous chondrocyte implantation (ACI) on a femoral chondral defect of the knee. MATERIALS AND METHODS: We evaluated 14 patients who had been operated on with ACI on the chondral defect of the knee between December 2000 and December 2005. There were 11 males and 3 females with the average age of 33 years (range: 17~44 years) and the mean size of the defect was 5.9 cm2 (range: 2.0~10 cm(2)). Seven cases were due to osteochondritis dissecans, and others were due to traumatic defect. The mean follow-up period was 26 months (range: 12~42 months). Lysholm's and Tegner's scores were used for evaluation. A 2nd look arthroscopic examination and a biopsy were carried out in 6 cases and MRI was done in 3 cases for evaluating cartilage regeneration. RESULTS: The mean Lysholm's and Tegner's scores were improved 60 to 84, and 2.4 to 4.1, respectively. According to the ICRS (International cartilage repair society) assessment, the gross appearance of the regenerated cartilage was graded as the following: 1 normal, 1 nearly normal, 3 abnormal and 1 severely abnormal. MRI demonstrated cartilage regeneration in 2 out of 3 cases. There were 2 cases of graft hypertrophy and 1 case of graft adhesion as complications. CONCLUSION: The clinical results were significantly improved according to Lysholm's and Tegner's scores. However, the gross appearances and histological results gave less satisfactory results. We conclude that a more sophisticated surgical technique and the long term follow-up results are necessary.

The Results of Autologous Chondrocyte Implantation with a Concomitant Injury / 대한정형외과학회잡지

PURPOSE: To evaluate the results of autologous chondrocyte implantation with a concomitant injury. MATERIALS AND METHODS: Sixty-seven chondral defects (39 cases, 36 patients), which were treated with autologous chondrocyte implantation, were analyzed with a minimum follow-up of 2 years. The cases were divided into the following five groups: 4 cases of a single chondral defect (group I), 3 cases of multiple chondral defects (group II), 5 cases of osteochondritis dissecans (group III), 9 cases of a single chondral defect with a concomitant injury (group IV), and 18 cases of multiple chondral defects with a concomitant injury (group V). The clinical outcomes were evaluated using the International Knee Documentation Committee (IKDC) subjective and objective scores and the International Cartilage Repair Society (ICRS) functional evaluation system. Arthroscopic examinations were performed on 12 cases and 21 chondral defects. RESULTS: The mean IKDC subjective score was 39.8 preoperatively, which improved to 64.1 postoperatively, and the IKDC objective score was C in 54% and D in 46%, which improved to A in 74%, B in 23% and C in 3%. The ICRS functional evaluation system was III in 82% of cases, and IV in 18% preoperatively, which improved to I in 15% and II in 85%, postoperatively. At the arthroscopic evaluation, the results of the ICRS system were I in 9%, II in 67%, and III in 24%. There was no significant difference between the single chondral defect and chondral defects with a concomitant injury. CONCLUSION: In the treatment of the multiple chondral defects with a concomitant injury, autologous chondrocyte implantation produced similar excellent clinical results to those of a single chondral defect.