Increased thickness of tertiary perimysium within cross-sections of fascicles within spastic muscle.

<p>Typical examples of light micrographs of Sirius Red stained cross-sections of FCU biopsies: (<b>A</b>) control muscle. (<b>B</b>) Spastic muscle. Bars represent 250 µm. (<b>C</b>) Individual data of tertiary perimysium thickness within FCU biopsies plotted as function of age. Mean thickness of tertiary perimysium in FCU (indicated by horizontal lines) of spastic subjects (n = 23) was significantly higher than in FCU of control subjects (n = 9).