{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T18:53:12Z","timestamp":1768243992408,"version":"3.49.0"},"reference-count":8,"publisher":"BMJ","issue":"1","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2025,12,10]]},"published-print":{"date-parts":[[2026,1]]},"abstract":"<jats:p>Trichorrhexis nodosa (TN) is a common hair shaft disorder characterised by node-like fracture points due to structural weakening. It can be congenital or acquired, with the latter often linked to physical or chemical trauma. This report presents a case of localised acquired TN in a teenage boy with asymptomatic white nodes over the parietal scalp. The condition was attributed to repetitive friction from a specific combing habit using a pocket-sized plastic-bristled comb. Trichoscopy revealed white nodules and broken shafts with a classic \u2018paintbrush\u2019 appearance, while light microscopy confirmed cortical fibre fraying and impending shaft fractures. This case underscores the diagnostic utility of trichoscopy and microscopy in differentiating TN from other hair shaft disorders and emphasises the importance of identifying behavioural causes. Patient education and behavioural modification, including the use of a wide-toothed comb, were key to management.<\/jats:p>","DOI":"10.1136\/bcr-2025-267406","type":"journal-article","created":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T15:30:14Z","timestamp":1768231814000},"page":"e267406","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Combing into trouble: localised acquired trichorrhexis nodosa"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3798-1207","authenticated-orcid":false,"given":"Gopikrishnan","family":"Anjaneyan","sequence":"first","affiliation":[{"name":"Department of Dermatology, Amrita Institute of Medical Sciences and Research Centre, Amrita Vishwa Vidyapeetham, Kochi, Kerala, India"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ashwini","family":"Ashokan","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Amrita Institute of Medical Sciences and Research Centre, Amrita Vishwa Vidyapeetham, Kochi, Kerala, India"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2026,1,12]]},"reference":[{"key":"2026011207300820000_19.1.e267406.1","doi-asserted-by":"crossref","first-page":"25","DOI":"10.1111\/j.1525-1470.2007.00327.x","article-title":"Trichorrhexis nodosa secondary to argininosuccinicaciduria","volume":"24","author":"Fichtel","year":"2007","journal-title":"Pediatr Dermatol"},{"key":"2026011207300820000_19.1.e267406.2","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1111\/j.1365-4632.2010.04768.x","article-title":"A practical, algorithmic approach to diagnosing hair shaft disorders","volume":"50","author":"Mirmirani","year":"2011","journal-title":"Int J Dermatol"},{"key":"2026011207300820000_19.1.e267406.3","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0190-9622(87)70001-2","article-title":"Structural abnormalities of the hair shaft","volume":"16","author":"Whiting","year":"1987","journal-title":"J Am Acad Dermatol"},{"key":"2026011207300820000_19.1.e267406.4","doi-asserted-by":"crossref","first-page":"34","DOI":"10.4103\/0974-7753.82138","article-title":"Localised acquired trichorrhexis nodosa of the scalp hair induced by a specific comb and combing habit - a report of three cases","volume":"3","author":"Martin","year":"2011","journal-title":"Int J Trichology"},{"key":"2026011207300820000_19.1.e267406.5","doi-asserted-by":"crossref","first-page":"34","DOI":"10.4103\/ijt.ijt_64_19","article-title":"Acquired Trichorrhexis Nodosa Secondary to Trichoteiromania: Prompt Diagnosis Using Trichoscopy","volume":"14","author":"Jindal","year":"2022","journal-title":"Int J Trichology"},{"key":"2026011207300820000_19.1.e267406.6","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1111\/j.1440-0960.1995.tb00969.x","article-title":"Hair shaft abnormalities: Part I","volume":"36","author":"Rogers","year":"1995","journal-title":"Australas J Dermatol"},{"key":"2026011207300820000_19.1.e267406.7","doi-asserted-by":"crossref","first-page":"211","DOI":"10.4103\/ijd.ijd_439_24","article-title":"Acquired Trichorrhexis Nodosa Confined to the Beard: A Rare Entity","volume":"70","author":"Garg","year":"2025","journal-title":"Indian J Dermatol"},{"key":"2026011207300820000_19.1.e267406.8","doi-asserted-by":"crossref","first-page":"e598","DOI":"10.1111\/ijd.16798","article-title":"Acquired trichorrhexis nodosa in association with hyperthyroidism","volume":"62","author":"Mathur","year":"2023","journal-title":"Int J Dermatol"}],"container-title":["BMJ Case Reports"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1136\/bcr-2025-267406","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T15:30:16Z","timestamp":1768231816000},"score":1,"resource":{"primary":{"URL":"https:\/\/casereports.bmj.com\/lookup\/doi\/10.1136\/bcr-2025-267406"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1]]},"references-count":8,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,1,12]]},"published-print":{"date-parts":[[2026,1]]}},"alternative-id":["10.1136\/bcr-2025-267406"],"URL":"https:\/\/doi.org\/10.1136\/bcr-2025-267406","relation":{},"ISSN":["1757-790X"],"issn-type":[{"value":"1757-790X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1]]}}}