Prospective evaluation of pin site infections in 39 patients treated with external ring fixation.

Introduction: Pin site infection is a common complication to external ring fixation. While the aetiology is well described, monitoring of onset, location, and the distribution of infection among the pin sites still needs further attention. The present pilot study evaluates the feasibility of a prospective registration procedure for reporting, evaluating, and monitoring of pin site infections in patients treated with external ring fixation. This may promote communication between team members and assist decision-making regarding treatment. Methods: A total of 39 trauma, limb deformity, and bone infection patients (15 female, 24 males; mean age 49 years (range: 12-88)) treated with external ring fixation were followed in the outpatient clinic using the pin site registration tool. Pin site infection (Checketts and Otterburn (CO) grade, onset, location), use of oral or intravenous antibiotics, and any unplanned procedures due to pin sites complications (wire removal and/or replacement, premature frame removal, amputation, etc.) were registered until frame removal. Results: The mean (SD) frame time was 164 (83) d (range: 44-499). We performed 3296 observations of 568 pin sites. Pin infection was registered in 171 of the 568 pin sites (30 %), of which 112 (65 %) were categorized as CO 1, 42 (25 %) as CO 2, 9 (5 %) as CO 3, and 8 (5 %) as CO 5. Neither CO 4 nor CO 6 was observed. A total of 35 patients (90 %) encountered CO 1-3 at least once during the observation time, while 1 patient (2.5 %) developed a major infection at eight pin sites (CO 5). Antibiotics were administered to $22/39$ (56 %) of the patients. Conclusion: In an effort to monitor pin site infections in this complex patient group and to ensure the best clinical outcomes, our registration procedure in the outpatient clinic helped to recognize pin site infections early and eased communication between team members providing a concise overview of the treatment course.