VERTEBRAE CANCELLOUS BONE STRENGTH MEASUREMENTS BY AN OSTEOPENETROMETER

The penetration strength of trabecular bone tissue of human lumbar ver tebrae was determined in vitro by the osteopenetrometer. The tests wer e performed in the frontal, middle, and back third of the vertebra bod y lateral side, in the upper and lower terminal plates, and in the pro cessus spinosus in three vertebrae of the age group 1 (19-25 years), f our vertebrae of the group 2 (40-60 years), and four of the group 3 (6 1-75 years). The data obtained show that the penetration of strength o f the human lumbar vertebrae diminishes with age nonuniformly: the mas t expressed decrease appears in the frontal and middle parts of the la teral side and in the processus spinosus, but very little change appea rs under the terminal plates. The significant correlation between the penetration strength in the processus spinosus and in the vertebrae bo dy could be useful for diagnostics of the vertebra state in vivo. Acco rding to the measured penetration strength in the processus spinosus, it is possible to indirectly estimate its value in the vertebra body.