Bone Abstracts

Objective: Muscular dystrophy is characterized by lower skeletal muscle quality, lower muscle strength and physical performance. The aim of the study was to assess regional muscle density and its correlation with regional muscle area in Duchenne muscular dystrophy (DMD) subjects and able bodied controls.

Method: Skeletal muscle pQCT (peripheral quantitative computed tomography) scans at the non-dominant forearm were performed in patients with muscle dystrophy at different ages and compared with muscular healthy patients with familiar short stature or diabetes type 1.

Results: We included 45 children and adolescence with clinical and molecular diagnosis of MD (2 Becker-Kiener, 2f) and 105 controls (68 f). Mean age for MD was 9.73±3.7 years and 14.77±4.6 years for controls. Younger MD patients were ambulatory, the majority of them were treated with intermittent glucocorticoids. Muscle density was constant between 70 and 80 mg/m³ in the control population (mean 77.90±2.16) irrespective of age and sex, whereas muscle density for MD was significantly reduced with 48.38±12.8 mg/m³ and decreased with age (r=−0.39, P=0.009). There was no correlation between muscle density and muscle cross sectional area (MCSA) for each of the groups. With age MCSA increased in controls (r=0.73, P<0.001) but not in MD.

Conclusions: In healthy or able bodied controls muscle density is a constant parameter. Measurements of this parameter in MD seem to reflect the progressive loss of muscle fibers and might be an early marker at a stage where muscle CSA is still within normal range.

Disclosure: The authors declared no competing interests.