Comparing exposed and buried Kirschner wires in fixation for pediatric supracondylar humerus fractures: A propensity score-matched study

Purpose To thoroughly compare the outcomes between exposed and buried Kirschner wires (K-wires) in fixation for pediatric supracondylar humerus fractures. Methods We examined patients who underwent surgery at our institution between January 2007 and June 2021. We investigated their age, sex, fracture pattern, number of K-wires used, whether they were exposed or buried, operative time, postoperative complications, number of outpatient visits, duration from surgery to K-wire removal, total length of hospitalization, and perioperative radiographic parameters. After propensity score matching, intergroup comparisons were performed to assess the differences in postoperative complication rate, number of outpatient visits, duration from surgery to K-wire removal, total length of hospitalization, and loss of reduction. Results Propensity score matching resulted in 43 pairs in both groups. Although more patients complained of skin irritation in the buried K-wire group, there was more backing out of the K-wire in the exposed K-wire group (p < 0.01). There were no significant differences in other complications. There were more outpatient visits in the buried K-wire group (p < 0.01). The duration from surgery to K-wire removal and the total length of hospitalization were significantly longer in the buried K-wire group (p < 0.01). There was no significant difference in the loss of Baumann's angle (p = 0.61), tilting angle (p = 0.48), or the development of rotation (p > 0.99) between groups. Conclusion More outpatient visits and longer lengths of hospitalization in the buried K-wire group may lead to increased costs and burden on parents.