1992 Volume 55 Issue Supplement Pages 211-216
The manageability of the hair is dependent on the surface composition of the hair shaft. Exogenously caused damage leads to unmanageability by massive superficial defects in the hair cuticle. The symptoms of trichorrhexis nodosa and trichoptilosis are present, and superficial horny scales are bent up and curve under in tunnel-like fashions. Appropriate hair care can improve these defects. Endogenous damage to the hair leading to unmanageability is characterized by spiral furrows along the shaft. It can not usually be improved by the use of care products.
The examples presented in the paper demonstrate that exogenous and endogenous causes of unmanageability are characterized by different alterations in the hair shaft.