Then his arms grew stiff, and he had to stop every half an hour to rest and stretch. He grumbled at this one; every time he had to limber up was time lost, words lost, inspiration running away. Reluctantly, he agreed to type out his stories on the computer, though half his enjoyment was sucked away by the unfamiliar clickety-click of the keys, instead of the scratchety-scritching of his fountain pen. The bright screen hurt his eyes, no matter how dim the technician tried to make the screen.
As time progressed, it was head that grew heavy with thoughts that wouldn't form properly, leaving words. Sentences that do not. Lapses in paragraphs. Sometimes. Work out no sense. Finally. Gave up.
a disorder in which an organ or tissue of the body wastes away/
any condition of abnormal development, often denoting the degeneration of muscles.