California Cosmetology Written ExamClient Consultation and AnalysisHard
A client complains that her hair has been breaking off in the middle of the shaft after months of frequent flat-ironing and chemical relaxing. On close inspection, the cosmetologist notices small, hard, white nodule-like swellings spaced along the hair shaft, with the hair snapping at those swollen points. Which hair shaft disorder does this describe?
- AMonilethrix
- BCanities
- CTrichorrhexis Nodosa
- DTrichoptilosis
Show answer & explanationAnswer & explanation
Correct answer: C. Trichorrhexis Nodosa
Trichorrhexis Nodosa is a hair shaft disorder in which the cuticle splits and frays at weak points, forming node-like swellings where fragments of the cortex separate, causing the hair to break easily at those nodes. It is most often caused by excessive physical or chemical damage, such as repeated heat styling and over-processing, matching the scenario described.
Why the other options are wrong
- A. Monilethrix is a congenital condition causing beaded, uniformly spaced constrictions, not damage-related nodes.
- B. Canities is loss of pigment causing gray hair, unrelated to shaft breakage.
- D. Trichoptilosis refers only to split ends at the hair tips, not nodes along the shaft.
Trichorrhexis Nodosa
A hair shaft disorder characterized by node-like swellings along the shaft where the cuticle has split and frayed, causing the hair to break easily at those points.
- Usually caused by excessive heat styling, chemical over-processing, or mechanical damage.
- Appears as whitish nodes or thickened points along an otherwise normal strand.
- Treatment focuses on reducing damage—trimming affected areas and using protective/reconstructive products.
Memory trick: Nodosa = 'knots on the shaft' that snap under stress.