Figure 5

Micro- Raman spectroscopy and computer assisted tomography analysis of AVNFH and control bone. (A) Box plot showing the ratio of phosphate to amide peaks (top panel), carbonate to amide peak (middle panel), and carbonate peak intensity, in control, adjacent non-diseased and AVNFH bone samples obtained using micro-Raman line scan analysis. All the three parameters were significantly reduced in necrotic regions compared to control bone. The carbonate peak intensity was not significantly different between control and non-diseased adjacent areas. (B) Photomicrographs obtained from Raman mapping analysis showing the distribution of carbonate and phosphate in control, adjacent non-diseased and necrotic regions. Shades of red indicate elevated levels and shades of blue indicate reduced levels. Shades of green indicate intermediate levels (refer to color scale). (C) same as in B, but for phosphate and amide peaks, (D) box plot showing quantitation of D. Median values derived from one hundred data points is shown. Carbonate to phosphate ratio progressively increased from control to adjacent non-diseased to necrotic areas, (E) same as in D, but for phosphate to amide ratio. Phosphate to amide ratio progressively decreased from control to adjacent non-diseased to necrotic areas, (F) box plot showing the comparison of median CT intensities quantified by Hounsfield unit values (HU) for Control (n = 4) and AVNFH (n = 6) bone samples. Median HU value that denotes the radio density on a CT scan was significantly lower in AVNFH patients compared to control individuals. Radio density is a surrogate measure for bone mineral density. All P values described in the figure panels were calculated using Student T-tests.