Abstract: A novel near infrared spectroscopic technique was used to characterize the joints in arthritis with comparison against normal joints. A beam of near infrared light was passed to joints through a fibre optic cable. Scattered light was collected by the same fibre bundle and a spectrum of the joint computed. Multivariate pattern recognition techniques identified regions of the spectrum which allowed discrimination between healthy and affected joints. Linear discriminant analysis resulted in correct classification of 74% of the joints. The high degree of similarity between mean spectra representing the early, late and control groups along with the significant between—subject variability in the data make diagnosis based on visual assessment of the spectra impossible. Linear discriminant analysis was therefore applied to spectra to determine if spectra could be classified by statistical methods as arising from early or late RA. Application of LDA resulted in correct classification of 74% of the joints.

Abstract: A novel near infrared spectroscopic technique was used to characterize the joints in arthritis with comparison against normal joints. A beam of near infrared light was passed to joints through a fiber optic cable. Scattered light was collected by the same fiber bundle and a spectrum of the joint computed. Multivariate pattern recognition techniques identified regions of the spectrum which allowed discrimination between healthy and affected joints. Linear discriminant analysis resulted in correct classification of 74% of the joints.

Abstract: Differences in the physical and chemical properties of synovial fluid from healthy and arthritic joints are detected by infrared spectroscopy. A beam of infrared light is directed at a sample of synovial fluid (either in its native form or prepared as a film) and changes in the physical and chemical properties of the fluid being analyzed are detected at one or more wavelengths to determine whether changes in the position, width, absolute intensity, relative intensity or shape of the infrared absorption have occurred which are characteristic of the arthritic condition.