EXPERIMENTAL CORRELATION BETWEEN T2-ASTERISK AND ULTIMATE COMPRESSIVESTRENGTH IN LUMBAR PORCINE VERTEBRAE

Rationale and Objectives. The authors used magnetic resonance (MR) ima ging to investigate the correlation between T2 measurements of trabec ular bone and the ultimate compressive strength of lumbar porcine vert ebrae. Methods. Five pigs that weighed 25-32 kg were sacrificed and im aged with a 1.5-T MR system. T2 of the lumbar vertebrae was measured from gradient-echo images. The vertebrae were individually compressed at a fixed speed in the direction of the spine until crushed. The maxi mum load a vertebra could resist was recorded. Results. T2 ranged fro m 7.1 to 14.5 msec. T2 determined from 5-mm coronal sections differed from that determined from axial and sagittal sections (P < .05). Betw een 2.9 and 5.4 kN of force (296-550 kg) was needed to crush a vertebr a. A linear correlation between the ultimate compressive strength and T2 of all vertebrae was observed for all imaging planes and section t hicknesses (P < .001, except for 10-mm sagittal images, for which P < .002). The T2 determined for the axial plane showed the best correlat ion with the ultimate compressive strength (r = -0.83). Conclusion. Th e correlation between T2 values and vertebral strength indicates that MR imaging may potentially be used to predict fracture risks in patie nts.