Expanding letter-specific dysgraphia to include font selectivity: A case report

Dear Sir, Letter-specific dysgraphia is a unique phenomenon that is rarely observed in clinical practice, first reported in 2018.[1] In this phenomenon, which has been potentially a form fruste of writer’s cramp, there is difficulty in forming specific letters, with the patient feeling as if stuck or taking time to initiate writing of these. Kinematic studies have indicated difficulties in initiation of writing the affected letter.[1,2] It is presumably due to difficulties in the generation of graphemes, with specific problems in writing-related effector motor programs.[1-3] Secondary causes of this form of specific dysgraphia have been reported, including space-occupying lesions of the left occipital area.[4] We report a patient who presented to us with a similar interesting phenomenon. A 60-year-old bank manager reported difficulty in signing bank documents for the past 1 year. He had specific difficulty in initiating his signature, which began with the cursive letter “S.” Having encountered this difficulty, he changed the font of the letter “S,” with which he was able to sign fluently. The initial difficulty was with a looping form of “S” written in an “ampersand (&)” style. In the modified form, the letter was a simple “S” [Video 1]. The problem would worsen as he continued to write the ampersand letter “S,” as he had to sign several bank documents at a stretch. There were no problems in continuing to write subsequent letters in his name, or the rest of the writing. This difficulty was present while initiating any word starting with this letter, but only when written in ampersand form. No difficulty was elicited in writing multiple sentences [Video S1] or other letters of the alphabet, or writing “s” in small case. There was no difficulty in drawing loops or spirals [Video S1]. There was no dystonic posturing or tremor of both upper limbs. No dystonic posturing was seen in the right hand when the patient wrote with the left hand. No clear improvement was noted if a more proximal joint was used to write or if the grip was changed. The remaining neurological examination was normal. Magnetic resonance imaging brain was unremarkable. {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video 1","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_xffgtvyg"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} {"href":"Single Video Player","role":"media-player-id","content-type":"play-in-place","position":"float","orientation":"portrait","label":"Video S1","caption":"","object-id":[{"pub-id-type":"doi","id":""},{"pub-id-type":"other","content-type":"media-stream-id","id":"1_m3o102n4"},{"pub-id-type":"other","content-type":"media-source","id":"Kaltura"}]} A few cases of letter-specific dysgraphia have been reported. Ganguly et al. reported a patient who had dysgraphia while writing in the Bengali script,[2] particularly letters that initiated with a “loop.” Another patient, reported by Prasad and Pal, also had difficulty, but in a single letter that also initiated with a circular loop.[1] In contrast to the observation by Ganguly et al.,[2] the font evincing difficulty in our patient did not require an initial circling but a straight bar at the bottom of the “S” [Figure 1], but subsequently required semi-circular movements, which are required for the usual “S” font as well. Additionally, in the patient reported by Ganguly et al., the difficulty was present at the outset on writing, whereas our patient developed difficulty after a period of writing. Unlike the cases described by Ganguly et al. and Prasad and Pal,[1,2] our patient had problems in the English letter alone and did not use the bud while initiating writing. Initiating writing with other letters with a cursive font, such as “U,” “N,” or “O,” was not associated with problems. This suggested a highly selective difficulty, which was specific to the font of the letter “S.” He also reported some difficulty in writing letters in the Edwardian script International Typeface Corporation other than the ampersand-style “S,” potentially supporting a font-specific issue. However, as this was not his usual writing script, some difficulty in expected, and this finding must be interpreted with caution. Moreover, his difficulty developed prominently as he continued to write but remained confined to the initial letter. It is a pertinent question why our patient and the previous cases should develop abnormalities in the effector-specific motor programs at a later age, having written in the same style for nearly their entire writing lives. Further work is required to elicit whether this dysgraphia is also associated with dystonic patterns.Figure 1: Sample of the patient’s handwriting showing the initial bar used to initiate the writing (arrows)Unlike the case reported previously by Prasad and Pal,[3] our patient encountered significant professional difficulty and posed a challenge in terms of treatment. Based on our current understanding of these selective patterns, whether recommending changing the signature to initiate with a different font of “S,” with which he did not have any challenges, is unclear. However, whether this can be a feasible and long-lasting solution to this problem needs longer observation. Acknowledgements We thank the patient for his cooperation.