Mechanical Properties of Ovariectomized Sheep Lumbar Vertebrae Treated with Synthetic-Bone-Mineral

Objectives: Osteoporosis is a progressive and debilitating skeletal disease characterized by loss of bone strength, thinning of cortical bone, and increased susceptibility to fractures. As one of the major load bearing structures, the lumbar vertebrae are the second most common sites of osteoporotic fractures in humans.

Prior studies in Sprague-Dawley rats have demonstrated significant improvement in bone health with the use of our calcium-phosphate-based synthetic bone mineral (SBM) biomaterial dietary supplement.
This study aims to elucidate the effect of SBM preparations on the mechanical properties of the lumbar vertebrae (L3) in ovariectomized sheep.
Methods: Twenty-four 3-3 ½-month-old sheep were divided into 4 groups: A: ovariectomized (OVX), B: sham-operated, C and D: OVX receiving diet supplemented with SBM with and without fluoride, respectively. All groups received low mineral based diets. The animals were sacrificed after 8 months and their lumbar vertebrae collected for analysis. The critical fracture load of L3 vertebral bodies were determined using diametral tensile test (Instron 5560, rate 1 mm/min).
Results: SBM significantly (P<0.05) improved bone strength; the diametral tensile strength of L3 vertebral body in sheep with SBM+F was 45.35% and with SBM without F was 48.65% higher than their OVX counterparts. The increased strength can be attributed to the higher mineral density and total volume of the lumbar vertebrae in SBM treated sheep.
Conclusions: With rising health care costs and efficacy concerns associated with the side effects from current therapies, new and more affordable and efficacious treatment options are needed for osteoporosis. This study showed that SBM, used as a dietary supplement, improved the mechanical properties and quality of osteoporotic bone.