CAN STRONG BACK EXTENSORS PREVENT VERTEBRAL FRACTURES IN WOMEN WITH OSTEOPOROSIS

Objective: To determine the influence of back extensor strength on ver tebral fractures in 36 women with osteoporosis. Design: We conducted a cross-sectional study of female patients with osteoporosis by assessi ng anthropometric variables, bone mineral density, muscle strength, le vel of physical activity, and radiographic findings in the spine. Mate rial and Methods: The 36 study subjects with osteoporosis, who ranged from 47 to 84 years of age, satisfied specific inclusion and exclusion criteria that minimized confounding factors related to pathophysiolog ic features, diet, and medications, A physical activity score was dete rmined for each subject on the basis of daily physical activities rela ting to homemaking, occupation, and sports. Results: The range of the physical activity scores-from 2 to 13-indicated that no subject was in volved in unusually demanding physical activities, Bone mineral densit y values ranged from 0.49 to 0.92 g/cm(2), Thoracic kyphosis ranged fr om 31.0 to 84.0 degrees, Isometric strength of the back extensor muscl es ranged from 7.3 to 34.0 kg, Statistical analysis demonstrated a sig nificant negative correlation between the strength of the back extenso r muscles and thoracic kyphosis, Significant negative correlations wer e also found between back extensor strength and the number of vertebra l compression fractures and between bone mineral density and the numbe r of vertebral fractures. Conclusion: The negative association between back extensor strength and both kyphosis and number of vertebral frac tures suggests that increasing back strength may prove to be an effect ive therapeutic intervention for the osteoporotic spine, In persons wi th stronger back muscles, the risk of vertebral fractures will likely decrease.