Abstract: BACKGROUND: The prevalence of osteoporosis is high in postmenopausal women, but muscle mass, grip strength, and how these factors affect osteoporosis are understudied, and the exact link between them has not been clarified.
OBJECTIVE: To investigate the correlation between muscle mass, grip strength, appendicular skeletal muscle index and bone mineral density in postmenopausal women with osteoporosis and to assess the potential values of these indices in predicting and diagnosing postmenopausal osteoporosis.
METHODS: Eighty-three postmenopausal women were collected from the outpatient clinic of the Third Affiliated Hospital of Guangzhou University of Chinese Medicine from February 2023 to January 2024. General data were collected. Bone mineral density was detected. T-value, muscle mass of each part, grip strength were recorded. The body mass index and appendicular skeletal muscle index were calculated. The patients were categorized into non-osteoporosis group (n=17) and postmenopausal osteoporosis group (n=66) according to T value and fracture history, and were statistically analyzed accordingly.
RESULTS AND CONCLUSION: (1) The body mass, body mass index, bone mineral density of the overall lumbar spine, muscle mass and appendicular skeletal muscle index were higher in the non-osteoporosis group than the osteoporosis group (P < 0.05). (2) Muscle mass was positively correlated with bone mineral density of the overall lumbar spine and individual vertebrae (P < 0.05). (3) Multiple stepwise linear regression analysis showed that body mass and grip strength were linearly and positively correlated with muscle mass; body height and muscle mass were linearly and positively correlated with grip strength, and body mass was linearly and negatively correlated with grip strength. Body mass index was linearly and positively correlated with bone mineral density, and age was linearly and negatively correlated with bone mineral density. (4) Analysis by receiver operating characteristic curve showed that: muscle mass (the area under the curve, sensitivity, specificity and critical value of muscle mass were 0.744, 76.50%, 74.20% and 36.50 kg, respectively, with P=0.002) and appendicular skeletal muscle index (the area under the curve, sensitivity, specificity and critical value of appendicular skeletal muscle index were 0.739, 82.40%, 62.10% and 5.81 kg/m2, respectively, and P=0.002) had good predictive value for postmenopausal osteoporosis. To conclude, a reduction in muscle mass and appendicular skeletal muscle index can help to predict the risk of postmenopausal osteoporosis, and the possibility of osteoporosis should be taken into account in postmenopausal women when muscle mass is < 36.50 kg or appendicular skeletal muscle index is < 5.81 kg/m2, in order to prevent the occurrence of postmenopausal osteoporosis.

Key words: postmenopausal osteoporosis, muscle mass, grip strength, appendicular skeletal muscle index, bone mineral density, engineered tissue construction