Grading cartilage damage with diffuse reflectance spectroscopy: Optical markers and mechanical properties.

Area of Science:

• Biomedical Optics
• Orthopedics
• Biophysics

Background:

• Osteoarthritis (OA) is a prevalent joint disease globally.
• Current clinical methods struggle with early-stage OA detection.
• Early identification of knee joint degradation is crucial to prevent progressive damage.

Purpose of the Study:

• To utilize diffuse reflectance spectroscopy (DRS) in the near-infrared (NIR) range for early OA detection.
• To establish optical markers for cartilage damage grades and assess mechanical properties.
• To develop a non-invasive method for identifying microscopic tissue changes in early OA.

Main Methods:

• Employing diffuse reflectance spectroscopy (DRS) in the NIR spectrum.
• Obtaining optical markers related to water content (OH-band) and protein content (CH-band).
• Analyzing spectral parameters including scattering and water content for correlation with cartilage properties and damage grades.

Main Results:

• DRS-derived water content strongly correlates with cartilage thickness (R=0.82) and viscoelastic relaxation time (R=0.7).
• Spectral parameters (water, protein, scattering) effectively discriminate between cartilage damage grades (P ≤ 10^-3).
• The developed approach shows potential for identifying microscopic lesions in early OA stages.

Conclusions:

• Diffuse reflectance spectroscopy (DRS) provides valuable optical markers for assessing cartilage health in osteoarthritis.
• This technique can non-invasively detect early-stage knee joint degradation.
• DRS may complement arthroscopy by identifying microscopic lesions, aiding in timely OA management.