The development of pin tract reactions and their sequelae is based on a complex series of events. Analysis of pin tract infections directly related to static external wire fixation at Kern Hospital for Special Surgery from 1981 through 1988 showed an incidence of 0.46%; however, the overall incidence is probably higher. A discussion of the pathogenesis and guidelines for prevention, diagnosis, and treatment are presented. The authors suggest that pin tract infections occur because of postoperative skin contamination, rather than intraoperative implantation.