Quantitative muscle ultrasound and muscle force in healthy children: A 4-year follow-up study

Introduction No longitudinal data on the normal development of muscle thickness (MT), quantitative muscle ultrasound echo intensity (EI), and muscle force (MF) in healthy children are yet available. Methods Reference values of MT, EI, and MF of 4 muscles from infancy to age 16 years were established during a 4-year follow-up period and correlated with age and growth. Results For most muscles, MT and MF correlated with growth and aging, with almost equal influences of weight and height. EI increased only slightly (1% per year) with height, weight, and age. Conclusions To use these reference values for repeated measurements, MF and MT can be corrected for either weight or height. It does not seem necessary to correct EI for these factors during follow-up of a few years. These results provide a basis for more precise detection of changes in muscle structure or force in neuromuscular disorders. Muscle Nerve 47: 856863, 2013