The Royal National Orthopaedic Hospital has completed an extensive trial of ACI versus MACI in the treatment of symptomatic osteochondral defects of the knee. A new technique has now been proposed which is quicker and easier to perform. This is the Gel-Type Autologous Chondrocyte Transplantation, CHONDRONTM. At Stanmore CHONDRON has been used for the past 17 months. Our aim was to assess the short term functional outcome of patients who have undergone CHONDRONTM using validated outcome scoring questionnaires. We retrospectively reviewed the notes of 43 patients that had undergone CHONDRONTM over one year ago and scored them using the Modified Cincinnati Score, the Visual Analogue Score and the Benltey Stanmore Functional Rating Score. The mean pre-operative Modified Cincinnati Score was 39.9, which improved to a mean of 59.8 post-operatively. The mean Visual Analogue Score improved from 6.7 to 5.1 post-operatively. The median Bentley Functional Rating Score was 3 pre-operatively and 2 post-operatively. These early results show that 76% of the patients who were treated with CHONDRONTM experienced a reduction in pain and improvement in post-operative function. In the patients in whom the symptoms were worse, the deterioration in score could be partly explained by numerous previous procedures on the same site, presence of early osteoarthritis or the presence of multiple osteochondral lesions. This highlights the importance of careful patient selection in order to gain maximum benefit from the procedure.RESULTS
CONCLUSIONS
The aim of this study was to determine whether the clinical outcome of autologous chondrocyte transplantation was dependent on the timing of a high tibial osteotomy in tibio-femoral mal-aligned knees. Between 2000 and 2005, forty-eight patients underwent autologous chondrocyte implantation with HTO performed at varying times relative to the second stage autologous chondrocyte implantation procedure. 24 patients had HTO performed simultaneously with their second stage cartilage transplantation, (the HTO Simultaneous Group). 5 patients had HTO prior to their cartilage procedure, (the HTO pre-ACI Group) and 19 had HTO performed between 1 to 4 years after their second stage cartilage implantation, (the HTO post-ACI Group). There were 29 men and 19 women with a mean age of 37 years (Range 28 to 50) at the time of their second stage procedure. With average follow-up of 72 months we have demonstrated a significant functional benefit in performing the HTO either prior to or simultaneously with the ACI procedure in the mal-aligned knee. The failure rate in the Post-ACI group was 45% compared to the Pre-ACI and Simultaneous group, with failure rates of 20% and 25%, respectively. An HTO performed prior to or simultaneously with an autologous chondrocyte implantation procedure in the mal-aligned knee, provides a significant protective effect by reducing the failure rate by approximately 50%.
Autologous chondrocyte implantation (ACI) is contra-indicated in a joint rendered unstable by a ruptured anterior cruciate ligament (ACL). We present our experience of ACI repair with ACL reconstruction Patients underwent arthroscopic examination and cartilage harvesting of the knee. A second operation was undertaken approximately six weeks later to repair the ruptured ACL with hamstring graft or Bone patella-Bone (BPB) and to implant the chondrocytes via formal arthrotomy. Three groups were assessed: Group 1: Simultaneous ACL Reconstruction and ACI; Group 2: Previous ACL Reconstruction with subsequent ACI repair; Group 3: Previously proven partial or complete ACL rupture, deemed stable and not treated with reconstruction with ACI procedure subsequently. Patients then underwent a graduated rehabilitation program and were reviewed using three functional measurements: Bentley functional scale, the modified Cincinnati rating system, and pain measured on a visual analogue scale. All patients also underwent formal clinical examination at review.Introduction
Methods
Articular cartilage implantation (ACI) and associated procedures (MACI = Matrix-assisted cartilage implantation) are now established treatments for osteochondral defects in the knee. The quality of repair in terms of histological appearance is frequently not known, whilst the correlation of histology results with functional outcomes remains undefined. Histological data of the quality of the repair tissue is sparse and a precise classification proved difficult. This was a single-centre, prospective study. Over 12 years (1998-2010) 406 patients that underwent articular cartilage implantation procedures at our institution (ACI = 170, MACI = 205) had biopsies taken at the 1-2 year interval, in order to assess whether these contained ‘hyaline-like’ cartilage, ‘mixed hyaline-like with fibrocartilage’, fibrocartilage or fibrous tissue alone. Histological sections of the biopsies were prepared and stained with haematoxylin, eosin and proteoglycan stains and viewed under polarised light. All biopsies were studied by a single histopathologist in a specialist, dedicated musculoskeletal laboratory. All patients were assessed by the Cincinnati, Bentley and Visual Analogue scores both pre-operatively and at the time of the review. The findings revealed that 56 patients healed with ‘hyaline-like’ cartilage (14.9%), 103 with ‘mixed’ (27.5%), 179 with fibrocartilage (47.7%) and 37 with fibrous tissue (9.9%). These findings showed that 42.4% of defects were filled with ‘hyaline-like’ or ‘mixed’ cartilage, with 70% of these achieving a ‘fair’ to ‘excellent’ functional outcome. This was also observed in the fibrocartilage group, where 72% achieved similar results. Predictably 89% of the patients that healed by fibrous tissue had a poor functional outcome. This study shows that 71% of patients whose osteochondral defects healed by either ‘hyaline-like’, ‘mixed’ or fibrocartilage experienced an improvement in the function. In contrast, only 11% of the patients whose defects filled with fibrous tissue, showed some functional improvement. Additionally, this data indicates the advantage of biopsies in assessing the overall results of cartilage implantation procedures.
