Fat infiltration, atrophy and hypertrophy of skeletal muscles demonstrated by X-ray computed tomography in neurological patients.

Since 1982, we have used X-ray computed tomography (CT) to study the skeletal muscles of neurological patients. We present here the findings in 23 patients with myogenic and 29 patients with neurogenic diseases. The method is convenient to demonstrate fat infiltration, atrophy and hypertrophy of skeletal muscles, but is of little help in differentiating between the 2 disease categories or individual diagnoses. The maximal isometric voluntary force of m. quadriceps femoris was measured in 13 of the patients with neurogenic, and in 10 of the patients with myogenic diseases. The power was compared with the cross-sectional area and the structural changes observed in the parenchyme of the muscles in the CT scans. A positive correlation was found between the size and the force of the muscle in both patient groups. The appearance of the muscular parenchyme was of little help to predict its function.