this may be spontaneous or secondary to mechanical factors like vigorous scratching or combing the hair .
a 19-year - old female patient presented with short , rough , and unruly hair on the scalp since childhood .
patient gave a history of knots getting caught in fine - toothed comb whenever the scalp was combed with breakage of few hairs .
there was no history of excessive cosmetic use or parlor activities for hair care . on examination ,
the scalp hairs were dry , curly , and short in length up to the nape of neck , transverse split ends ( trichoschisis ) were seen in majority of hairs [ figure 1 ] .
microscopic examination of the hair shaft revealed knotted portions of hair ; no other shaft abnormalities were noted except for trichoschisis at the distal portion of the shaft [ figure 5 ] .
short curly hair on the scalp small nodules on the distal portion of hair shaft sparse hair in the temporal region trichonodosis and trichoschisis in light microscopy
there are two types , one rare variety of unknown etiology involves abnormally growing scalp and body hair with spontaneous trichonodosis which is predisposed to splintering and fracturing . the second commoner type , encountered in patients with normal scalp and body hair , is considered secondary to mechanical forces such as combing and brushing .
the hairs in this type are dry and curly , but no abnormality in structure or growth pattern occurs .
rarely , more than one knot is found on a single hair and most were a simple half hitch knot .
when the hair of subjects with trichonodosis was combed or brushed , knots were observed to catch in fine toothed combs and to a lesser extent , in brushes . in those with extensive trichonodosis ,
breakage usually occurred at the knot , but proximal breakage and several uprooted telogen hairs were also seen .
kinky hair tends to be flat in cross section , whereas curly or straight hair is oval to round .
these flat or ribbon - shaped hairs do not lie flat on a level surface but remain spiral .
this recoiling may lead to an entanglement which , by chance , forms a knot that results in trichonodosis .
mechanical factors such as scratching , combing , washing or friction may produce tangling and knotting of hairs .
the pubic and thigh regions are most frequently involved since curliness of the hairs in those areas predisposes them to knotting .
if the knots are pulled excessively tight , transverse splintering of the hair shaft and simulation of trichorrhexis nodosa may result .
these knots resemble the ova of body , head and pubic lice and light microscopic examination is necessary for differentiation .
the nodules in trichonodosis are located distally , whereas the ova are located in the proximal shaft .
acquired type of trichonodosis due to mechanical factors is a common occurrence but reported less in literature .
spontaneous type of trichonodosis associated with abnormal scalp and body hair is a rare occurrence .
this type starts at an early age and hair breaks away after a particular length due to the fracture of hair shaft at the knot .
trichonodosis must be considered when patients with kinky hair complain of hair loss or breakage , and the cause is not apparent .
 trichonodosis is characterized by knotted hair on the distal portion of the hair shaft . 
 this may be spontaneous or secondary to mechanical factors like vigorous scratching or combing the hair . 
 we report a case of spontaneous trichonodosis with abnormal scalp and body hair . 