Molecular processes and structural alterations in laser reshaping of cartilage

Abstract

The effects of non-destructive laser irradiation on the structure and molecular processes in cartilage were studied using Raman microscopy, differential scanning calorimetry and biochemical analysis. A structural reorganization of the irradiated tissue similar to poliginization in polycrystalline solids was observed for the first time in a cartilage matrix. The difference in the Raman spectra of the irradiated and control samples was interpreted in term of a conformational alteration of glycosaminoglycan macromolecules in the reshaping mode. Laser induced modification of collagen macromolecules was not revealed by Raman spectroscopy. Thermal and biochemical analysis confirmed a preservation of triple helix for laser settings used for laser-induced stress relaxation and reshaping of cartilage.