Among the types of alopecia that can occur, many are associated with irregularities with the hair shaft. For example, cases of trichomalacia are characterized by plaques of hair loss with follicles consisting of deformed hairs. It can be caused by such traumatic causes as tics or trichotillomania, which is a psychological condition that involves the uncontrollable pulling of hair.
A scalp biopsy may reveal partially pulled out hair roots as a result of the traumatic causes that are deformed and twisted. There may also be evidence of fissures or grooves between the cells around and within the hair roots and the connective tissue.
While neither the traumatic causes of trichomalacia nor the resulting deformities result in any inflammatory reactions, many of the scalp’s hairs enter the resting, or telogen, phase of the hair cycle prematurely and result in excessive, diffuse hair loss some months later. The alopecia is similar in its effects to cases of telogenic alopecia that can result from nutritional deficiencies, traction or stress.