The abnormalities regarding hair shaft are very common and are indicating an underlying pathology. Microscopically tests can reveal different types of injuries, facilitating the giving of a diagnosis. The evaluations must be done on different parts of the scalp, so the diagnosis will be an accurate one for normal hair.
For abnormal hair, there can appear a condition called weathering, in which the hair shows some damage of the cuticle. Excessive washing, hairstyling and exposure to extreme temperatures may increase the weathering. Furthermore, split ends (or spared roots) are becoming more evident. Here are several abnormalities of hair shaft.
Fractures of the hair shaft
Also called Trichrorrhexis Nodosa, this is the most common abnormality, causing the loss of the cuticle, due to the appearance of swellings. What causes it is chemical or mechanical trauma. Ponytails or tight braiding can also induce this defect. Although it occurs in normal hair, it can also be a condition that leads to alopecia areata.
Trichoclasis
This means the “greenstick” hair shaft fracture of an intact cuticle, which has no abnormality. Trichoclasis may be found in other abnormalities or it can be caused by trauma or excessive hairstyling or hair wash. The effects are sporadic damages which can be easily treated.
Trichoschisis including trichothiodystrophy
Like in Trichoclasis, this is caused by the absence of the cuticle. It usually appears in cases of low-sulfur content, but it can also be sporadic. The consequences of Trichoschisis are alternating patterns of different colors that can be seen using a polarizer.
Oblique Fractures
Tapered Fracture. This fractures appear due to the nucleic acid that inhibits and the synthesis of proteins, causing the hair to have a pencil like look. This can lead to a bigger hair fracture that can go near the scalp.
Besides these, there are a lot of other abnormalities like Trichorrhexis Invaginata (or Bamboo Hair), or Hair Shaft Coiling and Twisting, so be careful with your hair and avoid excessive hairstyling, excessive hair wash and the exposure to extreme temperatures.
