Histopathology grading systems for characterisation of human knee osteoarthritis - reproducibility, variability, reliability, correlation, and validity

Both scoring systems implemented provide useful measures in the characterisation of knee osteoarthritis. It is of note that an additional parameter within the OACH score over the HHGS defines the extent of the disease, where the HHGS is a grade attributed to the most representative level of the biological aggression within the OA lesions. This study has confirmed the OACH system's utility in human knee OA and is supported by a significant correlation with the established HHGS.