Research article
The chondrogenic response to exercise in the proximal femur of normal and mdx mice
1 Arizona College of Osteopathic Medicine, Midwestern University, Glendale, AZ 85308, USA
2 The Pennsylvania State University, University Park, PA 16802, USA
BMC Musculoskeletal Disorders 2010, 11:198 doi:10.1186/1471-2474-11-198
Published: 3 September 2010Abstract
Background
Submaximal exercise is used in the management of muscular dystrophy. The effects of mechanical stimulation on skeletal development are well understood, although its effects on cartilage growth have yet to be investigated in the dystrophic condition. The objective of this study was to investigate the chondrogenic response to voluntary exercise in dystrophin-deficient mice.
Methods
Control and dystrophin-deficient (mdx) mice were divided into sedentary and exercise-treated groups and tested for chondral histomorphometric differences at the proximal femur.
Results
Control mice ran 7 km/week further than mdx mice on average, but this difference was not statistically significant (P > 0.05). However, exercised control mice exhibited significantly enlarged femur head diameter, articular cartilage thickness, articular cartilage tissue area, and area of calcified cartilage relative to sedentary controls and exercised mdx mice (P < 0.05). No differences were found between other treatment groups.
Conclusions
Mdx mice exhibit a reduced chondrogenic response to increased mechanical stimulation relative to controls. However, no significant reduction in articular dimensions was found, indicating loss of chondral tissue may not be a clinical concern with dystrophinopathy.



