Acquired Localized Hypertrichosis Induced by Internal Fixation and Plaster Cast Application
A 15-year-old boy was observed with some new excessive hairs on the right back of his hand for 3 weeks. Three months prior to this, he had been diagnosed with a closed fracture in the first metacarpus of right hand after a fall on the cement floor. He was operated with internal fixation by Kirschner wire on his right first metacarpus (). After the operation, a plaster of gypsum cast was applied from the wrist to his right elbow (). Six weeks later after the cast was removed, increased hair growth was localized on the right back hand where the cast was covered for internal fixation. Physical examination indicated a sheeted, coarse, dark hair area on his right back hand with a postsurgical scar which is approximate 5 cm in length (). There was no history of any systemic or topical medications known to cause hypertrichosis administered either before or after the surgery. The abnormal hair growth resolved spontaneously 4 months after the cast removal.