The term juxta-clavicular beaded lines is applied to a common condition characterized by lines adjacent to the clavicles and that are composed of tiny papules arranged in closely placed parallel rows resembling strands of beads. The beaded lines follow the lines of cleavage, are skin-colored, and are formed by globoid papules varying from 0.5 to 1.5 mm in size. Many of the papules are pierced by fine hair. The greatest incidence is in the 11- to 40-year age group, and the condition occurs more commonly in blacks. Results of our histologic studies indicate that the clinical features are caused by a linear arrangement of moderately hypertrophic sebaceous glands and sometimes dilatation of follicular canals associated with vellus follicles at these sites. The lesions are asymptomatic and probably represent an anatomical variant rather than a disease process.
Butterworth T, Johnson WC. Juxta-clavicular Beaded Lines. Arch Dermatol. 1974;110(6):891-893. doi:10.1001/archderm.1974.01630120041008