Size and X-ray density of normal and denervated muscles of the human leg and forearm.

An accurate assessment of muscle size and tissue density can be obtained by X-ray computed tomography. CAT scans of the extensor and flexor muscle compartments of the leg and forearm were performed on normal subjects to establish: normal ranges of muscle densities, and the effect of sex and side dominance on muscle size and density. The same muscle groups were studied in patients with nerve damage resulting in either total or very extensive denervation of the corresponding muscle compartments. In normal subjects muscle density is significantly lower in females and the effect of side dominance is more marked in the upper extremity. Denervated muscle compartments show reduced cross-section and density. Electrotherapy does not appear to be effective in preventing muscle atrophy.