Article

Knee Cartilage Reconstruction With Matrix-induced Autologous Chondrocyte Implantation

Article

Knee Cartilage Reconstruction With Matrix-induced Autologous Chondrocyte Implantation

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Abstract

Summary: A number of repair procedures have been used to address focal articular cartilage defects in the knee. Although traditional surgical techniques may alleviate pain and symptoms temporarily, these produce a fibrocartilage repair tissue, which is biomechanically inferior to hyaline articular cartilage. This has lead to the evolution of cell-based therapies, designed to regenerate a more biomechanically favorable hyaline-like tissue. Matrix-induced autologous chondrocyte implantation has become an established technique for the repair of fullthickness chondral defects in the knee. It is a two-stage procedure that involves an initial arthroscopic harvest of healthy cartilage, isolation and expansion of chondrocytes ex vivo, and subsequent reimplantation of the cells into the chondral defect. Over time and with an appropriate postoperative mechanical stimulus both protective and supportive of the tissue maturation process, these cells can migrate, proliferate, and produce a repair tissue that may fill the chondral defect, providing a hyaline-like tissue that can sustain the normal biomechanical demands placed on it. This study will outline our matrix-induced autologous chondrocyte implantation surgical techniques as developed since its introduction within our group, and the relative indications and contraindications for chondrocyte implantation.

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Article
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Article
The purpose of this study was to compare the outcomes of mosaic-type osteochondral autologous transplantation (OAT) and microfracture (MF) procedures for the treatment of the articular cartilage defects of the knee joint in young active athletes. Prospective randomized clinical study. Between 1998 and 2002, a total of 60 athletes with a mean age of 24.3 years (range, 15 to 40 years) and with a symptomatic lesion of the articular cartilage in the knee were randomized to undergo either an OAT or an MF procedure. Only those athletes playing in competitive sports at regional or national levels were included in the study. Fifty-seven athletes (95%) were available for a follow-up. There were 28 athletes in the OAT group and 29 athletes in the MF group. The mean duration of symptoms was 21.32 +/- 5.57 months and the mean follow-up was 37.1 months (range, 36 to 38 months), and none of the athletes had prior surgical interventions to the affected knee. Patients were evaluated using modified Hospital for Special Surgery (HSS) and International Cartilage Repair Society (ICRS) scores, radiograph, magnetic resonance imaging (MRI), and clinical assessment. An independent observer performed a follow-up examination after 6, 12, 24, and 36 months. At 12.4 months postoperatively, arthroscopy with biopsy for histologic evaluation was carried out. A radiologist and a pathologist, both of whom were blinded to each patient's treatment, did the radiologic and histologic evaluations. After 37.1 months, both groups had significant clinical improvement (P < .05). According to the modified HSS and ICRS scores, functional and objective assessment showed that 96% had excellent or good results after OAT compared with 52% for the MF procedure (P < .001). At 12, 24, and 36 months after surgery, the HSS and ICRS showed statistically significantly better results in the OAT group (P = .03; P = .006; P = .006). Younger athletes did better in both groups. No serious complications were reported. There was 1 failure in the OAT group and 9 in the MF group. The ICRS Cartilage Repair Assessment for macroscopic evaluation during arthroscopy at 12.4 months showed excellent or good repairs in 84% after OAT and in 57% after MF. Biopsy specimens were obtained from 58% of the patients and histologic evaluation of repair showed better scores (according to ICRS) for the OAT group (P < .05). MRI evaluation showed excellent or good repairs in 94% after OAT compared with 49% after MF. Twenty-six (93%) OAT patients and 15 (52%) MF patients returned to sports activities at the preinjury level at an average of 6.5 months (range, 4 to 8 months). Others showed a decline in sports activity level. At an average of 37.1 months (range, 36 to 38 months) follow-up, our prospective, randomized, clinical study in young active athletes under the age of 40 has shown significant superiority of OAT over MF for the repair of articular cartilage defects in the knee. We found that only 52% of MF athletes could return to sports at the preinjury level. Limitations of our study included a small number of athletes and a relatively short (3-year) follow-up. A long-term follow-up is needed to assess the durability of articular cartilage repair using these methods in young active athletes. Level I, Therapeutic study, randomized controlled trial, significant difference (a).
Article
Matrix-associated autologous chondrocyte transplantation/implantation (MACT/MACI) is a new operation procedure using a cell seeded collagen matrix for the treatment of localized full-thickness cartilage defects. A prospective clinical investigation was carried out in order to clarify whether this proves suitable and confirms objective and subjective clinical improvement over a period of up to 5 years after operation. Thirty-eight patients with localised cartilage defects were treated with MACT. Within the context of clinical follow-up, these patients were evaluated for up to 5 years after the intervention. Four different scores (Meyers score, Tegner-Lysholm activity score, Lysholm-Gillquist score, ICRS score) as well as the results of six arthroscopies and biopsies obtained from four patients formed the basis of this study. For 15 patients, 5 or more years had elapsed since the operation at the time this study was completed. It was possible to obtain results 5 years postoperatively from 11 (73.3%) of these 15 patients. Overall, we included 25 patients into the evaluation with a 2-year or longer postoperative period. Five years after transplantation 8 out of 11 patients rated the function of their knee as much better or better than before. Three of the four scores showed significant improvement compared to the preoperative value. One score, the Tegner-Lysholm score showed improvement, which, however, did not prove to be significant. The significantly improved results on three scores after 5 years suggest that MACT represents a suitable but cost-intensive alternative in the treatment of local cartilage defects in the knee.
Article
The results for autologous chondrocyte implantation (ACI) in the treatment of full thickness chondral defects in the knee are encouraging. At present two techniques have been described to retain the chondrocyte suspension within the defect. The first involves using a periosteal cover (ACI-P) and the second involves using a type I/III collagen membrane (ACI-C). To the authors knowledge there are no comparative studies of these two techniques in the current literature. We have therefore undertaken such a study to establish if there is a difference between the 2 techniques based on a clinical and arthroscopic assessment. A total of 68 patients with a mean age of 30.52 years with symptomatic articular cartilage defects were randomised to have either ACI-P (33 patients) or ACI-C (35 patients). The mean defect size was 4.54 cm2. All patients were followed up at 24 months. A clinical and functional assessment showed that 74% of patients had a good or excellent result following the ACI-C compared with 67% after the ACI-P at 2 years. Arthroscopy at 1 year also demonstrated similar results for both techniques. However, 36.4% of the ACI-P grafts required shaving for hypertrophy compared with none for the ACI-C grafts at 1 year. This study has shown no statistical difference between the clinical outcome of ACI-C versus ACI-P at 2 years. A significant number of patients who had the ACI-P required shaving of a hypertrophied graft. We conclude that there is no advantage in using periosteum as a cover for retaining chondrocytes within an osteochondral defect; as a result we advocate the use of an alternative cover such as a manufactured type I/III collagen membrane.
Article
Mosaic autogenous osteochondral transplantation has been used to treat large osteochondral defects. There is potential, previously unrecognized donor-site morbidity associated with osteochondral harvest from asymptomatic knees for the treatment of talar osteochondral defect lesions. Case series; Level of evidence, 4. Fifteen patients underwent mosaic osteochondral transplantation to treat a talar osteochondral defect lesion, with 11 patients available for follow-up. A Lysholm knee score was used to assess donor-site morbidity at a mean follow-up of 47 months (range, 7-77 months). Mean age was 29 years (range, 21-44 years). A single surgical team performed the mosaicplasties. Significance was determined using the Student t test. All patients had asymptomatic knees preoperatively. Mean postoperative Lysholm score was 81 (range, 49-100). By Lysholm criteria, 5 rated as excellent, 2 as good, and 4 as poor. No significant difference was detected in terms of the harvest method or the number of grafts obtained from those having an excellent rating versus those having a good/poor rating. Patients rated as good/poor cited knee instability in daily activities as the most common problem. One had knee pain and patellar instability after osteochondral harvest by lateral arthrotomy that required a subsequent lateral retinacular release and tibial tubercle osteotomy. This study demonstrates that donor-site morbidity after osteochondral harvest can be significant. In this population, those who experienced a decline in knee function had problems performing activities of daily living. When performing these procedures, the authors recommend that surgeons consider these risks and discuss them with their patients.
Article
We present our experience with the collagen-covered autologous chondrocyte implantation (CACI) technique. Thirty two implantations were performed in 31 patients. Clinical outcome was measured using the KOOS score and the 6-minute walk test, as well as an MRI scoring protocol (75% of patients had a complete data set for MRI follow-up) to describe the repair tissue generated by CACI. We have also correlated our MRI results with our clinical outcome. To the authors knowledge there are no comparative studies of MRI and clinical outcome following CACI in the current literature.
Article
Efficacious treatment of chondral and osteochondral defects of weightbearing articular surfaces is a daily challenge in musculoskeletal care. Autogenous osteochondral transplantation represents a possible solution for creating hyaline or hyaline-like repair in the affected area that has a noninflammatory pathoorigin. This paper discusses the experimental background and over 15 years of clinical experience with autologous osteochondral mosaicplasty. Several series of animal studies and subsequent clinical practice of over 1,000 mosaicplasty patients were assessed to confirm the survival of transplanted hyaline cartilage and fibrocartilage filling of donor sites located on relatively less weightbearing surfaces, as well as donor-site disturbances and morbidity. Histological evaluations of dog and horse implantations as well as several series of clinical evaluations in the human material are summarized in this paper. Clinical scores, different types of imaging techniques, second-look arthroscopies, histological examination of biopsy samples, and cartilage stiffness measurements were used to evaluate the clinical outcomes and quality of the transplanted cartilage. Analysis of clinical scores has shown good to excellent results in 92% of patients with femoral condylar implantations, 87% of tibial resurfacements, 74% of patellar and/or trochlear mosaicplasties and 93% of talar procedures. Longterm donor-site complaints measured by the Bandi score were minor and present only in 3% of patients. 81 out of the 98 control arthroscopies represented congruent and good gliding surfaces and histologically proven survival of the transplanted hyaline cartilage as well as fibrocartilage covering of the donor sites. Complications in the entire patient group were four deep infections and four deep venous thromboses. In nearly 8% of the cases excessive intraarticular bleeding was observed in the early postoperative period, as a minor complication of the procedure. Multicentric, comparative, prospective evaluation of 413 arthroscopic resurfacing procedures (mosaicplasty, Pridie drilling, abrasion arthroplasty and microfracture cases in homogenised subgroups) demonstrated that mosaicplasty resulted in favourable clinical outcome in the long-term follow-up compared to other three techniques. Durability of the early results was confirmed in long-term evaluations both of the femoral condylar implantations and talar mosaicplasties. According to our encouraging results in this increasingly large series, supported by similar findings from other centres, it seems that autologous osteochondral mosaicplasty may be an alternative for small and medium-sized focal chondral and osteochondral defects of weightbearing surfaces of the knee and other weightbearing synovial joints.
Article
To determine the effectiveness of 'accelerated' compared to 'traditional' post-operative load bearing rehabilitation protocols following matrix-induced autologous chondrocyte implantation (MACI). A randomized controlled study design was used to investigate clinical, biomechanical and radiographic assessment at 3 months post-surgery in 62 patients following MACI to the medial or lateral femoral condyle. Both rehabilitation interventions sought to protect the implant for an initial period, then incrementally increase load bearing. Under the 'accelerated' protocol, patients reached full weight bearing at 8 weeks post-surgery, compared to 11 weeks for the 'traditional' group. Patients in the 'accelerated' group achieved greater 6 min walk distances and daily activity levels as measured by accelerometry (P<0.05) compared to the 'traditional' group. Furthermore, the 'accelerated' group reported significantly better improvement in knee pain at 12 weeks as indicated by the Knee Injury and Osteoarthritis Outcome Score (P<0.05), and regardless of the rehabilitation protocol employed, no patient suffered any adverse effect to the implant as assessed by magnetic resonance imaging at 3 months. Comparison of each rehabilitation group with an unaffected control group revealed a significant difference in peak knee adduction and flexion moments for the traditional group (P<0.05). However, there was no difference for accelerated patients (P>0.05), which may demonstrate a faster return to knee loading patterns typically observed in unaffected subjects. The 'accelerated' load bearing approach that reduced the length of time spent ambulating on crutches resulted in reduced knee pain, improved function, no graft complications and may speed up the recovery of normal gait function. Patient follow-up to at least 24 months would be required to observe longer-term graft outcomes.