The ridgeback anomaly. A new follicular pattern of the scalp

A patient with an anomaly of hair pattern development is described. Scalp hair follicles generally grow at a downward inclination to the scalp surface. Normal whorled patterns appear in the posteroparietal area. The patient described was noted to have a whorled hair pattern located over the right temporoparietal region, growing in a clockwise direction. The remainder of the scalp adopted the upward follicular growth pattern of the posterior portion of the whorl, directed toward the apical anatomic axis. A ridge of hair over the nape of the neck reversed direction, similar to hair growth on the Rhodesian Ridgeback dog, growing in a downward manner. The relationship of this new hair pattern to current theories of scalp hair pattern development is reviewed.