Matrix-induced autologous chondrocyte implantation (MACI) in the knee
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Matrix-induced autologous chondrocyte implantation (MACI) has been in use for chondral defect repair since 2000, but to date, only little is known about its histological outcomes in the repair of knee cartilage defects. This prospective multicentre study aims to evaluate (1) the quality of the repair tissue obtained from biopsies taken during second-look arthroscopy and (2) the relationship between the histological outcome, the macroscopic appearance of the repair and the patients’ functional status.
Thirty-three second-look core biopsies from 30 patients treated with MACI were analysed. At the time of biopsy, the surgeon reported the reason for the second-look arthroscopy, the quality of the repair tissue and the patient’s functional status on a standardised form. Biopsies together with patient data were sent to our centre to undergo blind histological evaluation and data analysis.
The median overall ICRS II histological score of the examined population was 57 (1st–3rd quartile 41–75). According to the ICRS cartilage repair assessment (CRA) arthroscopic evaluation, 10 biopsies (30%) were classified as normal, 17 (51%) as nearly normal, 4 (12%) as abnormal and 2 (6%) as severely abnormal. The histological outcome was not significantly related either to the macroscopic appearance of the lesion or to the patient’s functional status at the time of biopsy.
In the examined population, the macroscopic appearance of the repair tissue gave an overly favourable impression in comparison with the real histological composition of the tissue, which was possibly still maturing in many cases. The healing process after MACI needs to be better understood through a larger histological study, and a longer follow-up is needed to better clarify the relationship between histology and long-term functional status.
Level of evidence
KeywordsCartilage Autologous chondrocyte implantation MACI Histology Core biopsy
The authors would like to acknowledge the following orthopaedic surgeons for providing biopsies and helping with patients’ data collection: Dr. Claudio Zorzi—Verona; Dr. Franz Erschbaumer—Bressanone; Dr. Vittorio Zaffarana—Vigevano; Dr. Corrado Bait, Dr. Roberto D’Anchise, Dr. Antonio Memeo, Dr. Alberto Ventura and Dr. Piero Volpi—Milano; Dr. Nicolo’ Coletti—Oderzo; Dr. Daniele Clementi—Bollate; and Dr. Roberto Pessina—Vicamerate. The authors would like to thank Dr. Dan Reynolds (University of Cambridge) for the help in editing this manuscript.
- 1.Bartlett W, Skinner JA, Gooding CR, Carrington RW, Flanagan AM, Briggs TW, Bentley G (2005) Autologous chondrocyte implantation versus matrix-induced autologous chondrocyte implantation for osteochondral defects of the knee: a prospective, randomised study. J Bone Joint Surg Br 87:640–645PubMedCrossRefGoogle Scholar
- 5.Brun P, Dickinson SC, Zavan B, Cortivo R, Hollander AP, Abatangelo G (2008) Characteristics of repair tissue in second-look and third-look biopsies from patients treated with engineered cartilage: relationship to symptomatology and time after implantation. Arthritis Res Ther 10:R132–R141PubMedCrossRefGoogle Scholar
- 7.Cherubino P, Grassi FA, Bulgheroni P, Ronga M (2003) Autologous chondrocyte implantation using a bilayer collagen membrane: a preliminary report. J Orthop Surg (Hong Kong) 11:10–15Google Scholar
- 11.ICRS cartilage repair assessment (2000). ICRS cartilage injury evaluation package. Available at: http://www.cartilage.org/_files/contentmanagement/ICRS_evaluation.pdf. Accessed April 2011
- 14.Loken S, Ludvigsen TC, Hoysveen T, Holm I, Engebretsen L, Reinholt FP (2009) Autologous chondrocyte implantation to repair knee cartilage injury: ultrastructural evaluation at 2 years and long-term follow-up including muscle strength measurements. Knee Surg Sports Traumatol Arthrosc 17:1278–1288PubMedCrossRefGoogle Scholar
- 15.Mainil-Varlet P, Aigner T, Brittberg M, Bullough P, Hollander A, Hunziker E, Kandel R, Nehrer S, Pritzker K, Roberts S, Stauffer E (2003) Histological assessment of cartilage repair: a report by the Histology Endpoint Committee of the International Cartilage Repair Society (ICRS). J Bone Joint Surg Am S2:45–57Google Scholar