Fatty degeneration of gluteus minimus muscle as a predictor of falls.

The cause of falls is multifactorial, however, hip fractures in elderly would be prevented if accidental falls are predictable. We assessed magnetic resonance images of 38 patients with groin pain after taking a fall whose fracture could not be detected by plain X-rays, and 45 patients with no episode of falls. Their ages were over 65 years. Fatty degeneration of muscles, gluteus maximus, gluteus medius, gluteus minimus, obturator externus, adductor longus, rectus femoris and iliopsoas muscles, were evaluated by Goutallier's staging. Odds ratio was calculated by a logistic regression analysis allocating dependent variable for falls and independent variables for Goutallier's stage, age and gender. The fatty degeneration of gluteus maximus muscle was generalized, while that of gluteus minimus muscle was unevenly distributed, especially in anterior area. Gluteus minimus muscle initiated its fatty degeneration earlier than gluteus medius muscle. Odds ratio of falling was 3.2 (95% confidence intervals: 1, 14, 8.94) for Goutallier' stage of the gluteus medius muscle. Fatty degeneration of gluteus medius muscle has a crucial role in providing stability of the pelvis including hip joint. Evaluating fatty streaks in the gluteus minimus muscle could help give early indication to those who have a higher risk of falling.