title: Are atrophic long-bone nonunions associated with low-grade infections?
abstract: Impaired fracture healing, especially when associated with bacterial infection, is a severe complication following long-bone fractures and requires special treatment. Because standard diagnostic techniques might provide falsely negative results, we evaluated the sonication method for detection of bacteria on implants of patients with fracture nonunions. A total of 49 patients with a nonunion (group NU) and, for comparison, 45 patients who had undergone routine removal of osteosynthetic material (group OM), were included in the study. Five different diagnostic methods (culture of tissue samples, culture of intraoperative swabs, histopathology of tissue samples, culture of sonication fluid, and 16S ribosomal DNA polymerase chain reaction of sonication fluid) were compared and related to clinical data. Among the diagnostic tests, culture of sonication fluid demonstrated by far the highest detection rate of bacteria (57%) in group NU, and rather unexpectedly 40% in group OM. Culture of sonication samples also revealed a broad spectrum of bacteria, in particular Propionibacterium spp. In conclusion, our results indicate that more bacteria can be detected on implants of patients with atrophic nonunions of long-bone fractures by means of the sonication procedure, which provides a valuable additional diagnostic tool to decide on a surgical procedure (eg, two-step procedure) and to further specify antimicrobial therapy.
authors.affiliation: Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Dapunt
authors.affiliation: HTRG-Heidelberg Trauma Research Group, Trauma and Reconstructive Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Ole
authors.initials: O
authors.lastname: Spranger
authors.affiliation: Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Simone
authors.initials: S
authors.lastname: Gantz
authors.affiliation: Department for Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg, Germany.
authors.forename: Irene
authors.initials: I
authors.lastname: Burckhardt
authors.affiliation: Department for Infectious Diseases, Medical Microbiology and Hygiene, Heidelberg, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Zimmermann
authors.affiliation: HTRG-Heidelberg Trauma Research Group, Trauma and Reconstructive Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Gerhard
authors.initials: G
authors.lastname: Schmidmaier
authors.affiliation: HTRG-Heidelberg Trauma Research Group, Trauma and Reconstructive Surgery, Center for Orthopedics, Trauma Surgery and Spinal Cord Injury, Heidelberg University Hospital, Heidelberg, Germany.
authors.forename: Arash
authors.initials: A
authors.lastname: Moghaddam
keywords: osteomyelitis; osteosynthetic material; sonication