title: Magnetic resonance observation of cartilage repair tissue (MOCART) for the evaluation of autologous chondrocyte transplantation: determination of interobserver variability and correlation to clinical outcome after 2 years.
abstract: In an observational study, the validity and reliability of magnetic resonance imaging (MRI) for the assessment of autologous chondrocyte transplantation (ACT) in the knee joint was determined. Two years after implantation, high-resolution MRI was used to analyze the repair tissue with nine pertinent variables. A complete filling of the defect was found in 61.5%, and a complete integration of the border zone to the adjacent cartilage in 76.9%. An intact subchondral lamina was present in 84.6% and an intact subchondral bone was present in 61.5%. Isointense signal intensities of the repair tissue compared to the adjacent native cartilage were seen in 92.3%. To evaluate interobserver variability, a reliability analysis with the determination of the intraclass correlation coefficient (ICC) was calculated. An "almost perfect" agreement, with an ICC value >0.81, was calculated in 8 of 9 variables. The clinical outcome after 2 years showed the visual analog score (VAS) at 2.62 (S.D. +/-0.65). The values for the knee injury and osteoarthritis outcome score (KOOS) subgroups were 68.29 (+/-23.90) for pain, 62.09 (+/-14.62) for symptoms, 75.45 (+/-21.91) for ADL function, 52.69 (+/-28.77) for sport and 70.19 (+/-22.41) for knee-related quality of life. The clinical scores were correlated with the MRI variables. A statistically significant correlation was found for the variables "filling of the defect," "structure of the repair tissue," "changes in the subchondral bone," and "signal intensities of the repair issue". High resolution MRI and well-defined MRI variables are a reliable, reproducible and accurate tool for assessing cartilage repair tissue.
authors.affiliation: Department of Traumatology, Center for Joint and Cartilage, Medical University of Vienna, Waehringer, Austria. stefan.marlovits@meduniwien.ac.at
authors.forename: Stefan
authors.initials: S
authors.lastname: Marlovits
authors.forename: Philipp
authors.initials: P
authors.lastname: Singer
authors.forename: Philip
authors.initials: P
authors.lastname: Zeller
authors.forename: Irena
authors.initials: I
authors.lastname: Mandl
authors.forename: Jörg
authors.initials: J
authors.lastname: Haller
authors.forename: Siegfried
authors.initials: S
authors.lastname: Trattnig
mesh_terms: D000328:Adult; D019902:Chondrocytes / Q000637:transplantation*; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000627:therapeutic use; D007718:Knee Injuries / Q000473:pathology / Q000601:surgery*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D020370:Osteoarthritis, Knee / Q000473:pathology / Q000601:surgery*; D011183:Postoperative Complications / Q000175:diagnosis; D011446:Prospective Studies; D019736:Prostheses and Implants; D014182:Transplantation, Autologous; D016896:Treatment Outcome
chemical_list: D006820:Hyaluronic Acid