We report the initial 2 and 3 year follow-up results of this randomised controlled trial of autologous chondrocyte implantation (ACI) using porcine-derived collagen membrane as a cover (ACI-C) versus matrix-carried autologous chondrocyte implantation (MACI) for the treatment of osteochondral defects of the knee. 217 patients were randomised to have either ACI (92 patients) or MACI (125 patients). The mean age in each group was 35.1 and 33 years respectively. There were equal proportion of males and females and there was no difference in the size of lesions in each of the treatment groups. One year following surgery, patients underwent check arthroscopy (with or without biopsy) to assess the graft. Functional assessment was performed yearly by using the Modified Cincinatti Knee score, the SF-36 score, the Bentley Functional Rating Score and the Visual Analogue Score.Introduction
Methods
To investigate (1) The relationship between macroscopic grading and durability of cartilage repair following collagen-covered autologous chondrocyte implantation (ACI-C) in the knee; (2) The influence of histology on durability of cartilage repair; (3) The relationship between macroscopic appearance and histology of repair tissue. The modified Cincinnati scores (MCRS) of eighty-six patients were evaluated prospectively at one year and at the latest follow-up (mean follow-up = 4.7yrs. Range = 4 to 7 years). Needle biopsies of their cartilage repair site were stained with Haematoxylin and Eosin and some with Safranin O and the neo-cartilage was graded as hyaline-like (n=32, 37.2%), mixed fibro-hyaline (n=19, 22%) and fibro-cartilagenous tissue (n=35, 40.7%). Macroscopic grading of the repair tissue using the international cartilage repair society grading system (ICRS) was available for fifty-six patients in the study cohort. Statistical analyses were performed to investigate the significance of histology and ICRS grading on MCRS at 1 year and at the latest follow-up.Aims
Patients and methods
The results for autologous chondrocyte implantation (ACI) in the treatment of osteochondral 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 flap harvested from the distal femur and the second involves using a type I/III collagen membrane. To the authors' knowledge there are no comparative studies of these two techniques in the current literature. A total of 68 patients with a mean age of 30.52 years (range 15 to 52 years) with symptomatic articular cartilage defects were randomised to have either ACI with a periosteal cover (33 patients) or ACI with a type I/III collagen cover (35 patients). The mean defect size was 4.54 cm2 (range 1 to 12 cm2). All patients were followed up at 24 months. A functional assessment using the Modified Cincinnati score showed that 74% of patients had a good or excellent result following the ACI with collagen cover compared with 67% after the ACI with periosteum cover at 2 years (p>0.05). Arthroscopy at 1 year also demonstrated similar results for both techniques. However, 36.4% of the periosteum covered grafts required shaving for hypertrophy compared with 1 patient for the collagen covered technique. This prospective, randomised study has shown no statistical difference between the clinical outcome of ACI with a periosteal cover versus ACI with a collagen cover at 2 years. A significant number of patients who had the ACI with periosteum technique required shaving of a hypertrophied graft within the first year of surgery. We conclude that there is no advantage in using periosteum as a cover for retaining the chondrocytes within an osteochondral defect; as a result we advocate the use of an alternative cover such as a porcine-derived, type I/III collagen membrane.
We report on minimum 2 year follow-up results of 71 patients randomised to autologous chondrocyte implantation (ACI) using porcine-derived collagen membrane as a cover (ACI-C) and matrix-induced autologous chondrocyte implantation (MACI) for the treatment of osteochondral defects of the knee. ACI is used widely as a treatment for symptomatic chondral and osteochondral defects of the knee. Variations of the original periosteum-cover technique include the use of porcine-derived type I/type III collagen as a cover (ACI-C) and matrix-induced autologous chondrocyte implantation (MACI) using a collagen bilayer seeded with chondrocytes.Purpose
Introduction
