Comparison of in Vitro Young and Old Lumbar Vertebrae of Ewes Related to Bone Density and Compression Strength

Abstract

An animal model (the ewe) was used to study the mechanical properties of lumbar vertebrae and to compare these properties with the bone mineral density. We measured the bone mineral density for lumbar vertebrae of 10 ewes for L2 & L5 for5 young ewes mean age 2 years and 5 old ewes mean age 8 years old. Compression test was conducted on ewes lumbar vertebrae L2 & l5 for young ewes and old ewes.There was significance differences between both group related to bone mineral density , compressive force , and young’s modulus. There was strong correlation between the mechanical properties and bone mineral density.Bone mineral density correlated with the mechanical properties and it is not surprising that an orthopedic device used with poorly mineralized bone can have lower mechanical fixation strength than the same device with well-mineralized bone.