Optical Coherence Tomography in Articular Cartilage Assessment

Optical coherence tomography (OCT) is a non-invasive imaging modality that utilises near-infrared light to produce micrometre-scale cross-sectional images of biological tissues. In the context of articular cartilage, OCT offers real-time visualisation of surface and subsurface architecture with resolution far exceeding conventional clinical imaging. By analysing back-scattered light intensity and polarisation changes, OCT can detect early morphological alterations—such as surface fibrillation, thinning and subsurface fissures—and provide quantitative measures of collagen organisation through birefringence. Innovations have extended OCT to polarisation-sensitive modes, depth-resolved segmentation and strain rate tomography, enabling assessment of mechanical properties and structural zonation. These capabilities have broad implications for early osteoarthritis diagnosis, intraoperative guidance during arthroscopy, monitoring of repair strategies and the development of engineered cartilage constructs. As OCT systems become more compact and compatible with handheld or arthroscopic probes, their translation into clinical practice promises to improve the detection and management of joint degeneration worldwide.

Research from Nature Portfolio

Recent studies have demonstrated the capacity of polarisation-sensitive OCT combined with mechanical indentation to quantify subtle changes in early cartilage degeneration. In a bovine model, cartilage subjected to controlled compressive loading exhibited distinct birefringent banding patterns that were captured by polarisation-sensitive OCT. By calculating a birefringence coefficient across indented and non-indented regions, researchers were able to discriminate healthy from early osteoarthritic tissue with high statistical confidence. This work highlights the potential for in vivo application of polarisation-sensitive OCT as a non-destructive diagnostic tool for the detection and staging of early osteoarthritis.

Optical Coherence Tomography in Articular Cartilage Assessment publication trend

The graph below shows the total number of articles in optical coherence tomography in articular cartilage assessment across all publications each year (not limited to Nature Index journals).

Technical terms

Optical Coherence Tomography (OCT): A non-invasive imaging method using infrared light to generate high-resolution cross-sectional images of tissue microstructure.

Polarisation-sensitive OCT (PS-OCT): An extension of OCT that measures changes in the polarisation state of light to assess tissue birefringence and collagen organisation.

Birefringence Coefficient (BRC): A quantitative parameter derived from PS-OCT that reflects the degree of optical anisotropy and collagen alignment in cartilage.

Stress Relaxation Optical Coherence Straingraphy (SR-OCSA): An OCT-based method that maps viscoelastic properties by evaluating strain rate attenuation under mechanical loading.

References

1. High-resolution optical coherence tomographic imaging of osteoarthritic cartilage during open knee surgery. Arthritis Research & Therapy (2005).
2. Quantifying birefringence in the bovine model of early osteoarthritis using polarisation-sensitive optical coherence tomography and mechanical indentation. Scientific Reports (2018).
3. Slope-based segmentation of articular cartilage using polarization-sensitive optical coherence tomography phase retardation image. Journal of Biomedical Optics (2019).
4. Changes in viscoelastic properties of articular cartilage in early stage of osteoarthritis, as determined by optical coherence tomography-based strain rate tomography. BMC Musculoskeletal Disorders (2019).