Muscle Quality Index as a Predictor of Hip Osteoarthritis

Objective: To determine the utility of the muscle quality index (MQI) as a predictor of osteoarthritis (OA) and to assess the influence of strength and body composition manifestations in subjects with hip OA. Methods: Fifty subjects (21 men and 29 women, 66.4 ± 5.3 years) participated in this study. Of them, 25 subjects had unilateral hip OA, and 25 healthy subjects. The 2 groups were matched by age and sex. We evaluated muscle perimeter, length of the upper limb, body mass, and administered the sit-to-stand test, which measures the time it takes to rise and sit 10 times, and the MQI, in addition to the maximum voluntary isometric contraction in hip flexion and extension movements. Results: The OA group presented significantly (P <.05) higher body mass index, but lower fat mass and greater leg length. In turn, significant differences were observed between the groups for the sit-to-stand test (P =.002) and, as a consequence, in the MQI (P =.003). The binary logistic regression analysis shows that a higher MQI is a protective factor against OA, with the cut-off point being 144.20. Conclusion: The MQI is a complementary tool for the diagnosis and monitoring of OA in elderly people.