plango to beat one's breast. Seems plango is the most direct Latin translation. Not sure if this is the root of any other English words that might give a better sense of the original use of the phrase. I did find that back in the days of legitimate breast-beating, some chose to smite:
Dysgraphia is a transcription disability, meaning that it is a writing disorder associated with impaired handwriting, orthographic coding (orthography, the storing process of written words and processing the letters in those words), and finger sequencing (the movement of muscles required to write).
They may lack basic grammar and spelling skills (for example, having difficulties with the letters p, q, b, and d), and often will write the wrong word when trying to formulate their thoughts on paper. The disorder generally emerges when the child is first introduced to writing. Adults, teenagers, and children alike are all subject to dysgraphia. Dysgraphia should be distinguished from agraphia, which is an acquired loss of the ability to write resulting from brain injury, stroke, or progressive illness.