Histopathological analysis for human articular cartilage using a Raman probe system

The molecular pathogenesis of degenerative alterations in articular cartilage is still not fully understood. Raman spectroscopy using a fiber-optic probe system is a promising approach for the early diagnosis and prevention of joint disorders such as osteoarthritis.

This study aims to characterize the degenerative changes in the joint articular cartilage using a hollow-core fiber Raman probe designed for future arthroscopic use.

Human articular cartilage specimens were obtained from 12 patients who underwent knee ( $n=5$ ) or shoulder ( $n=7$ ) arthroplasty. All surgical specimens were measured ex vivo after fixation in 10% neutral buffered formalin. The articular cartilage tissues at the knee, hip, and shoulder joints were obtained from a single cadaver donor. Raman spectra of the cartilage specimens were acquired and analyzed using a handheld Raman probe system.

The hollow-core fiber Raman probe detected molecular differences between less-degenerated and degenerated areas in human shoulder and knee articular cartilage ex vivo, with clearer separation in the knee, and additionally revealed joint-specific baseline spectral features among cadaveric shoulder, hip, and knee cartilage.

These results support the novelty and translational potential of this probe as a future in vivo arthroscopic tool for objective molecular assessment of cartilage degeneration.