Department of Orthopedic Surgery and Sports Medicine, Amsterdam UMC location University of Amsterdam, Amsterdam, the Netherlands.
Amsterdam Movement Sciences, Musculoskeletal Health, Amsterdam, the Netherlands.
J Orthop Trauma. 2024 Aug 1;38(8):452-458. doi: 10.1097/BOT.0000000000002822.
To determine (1) the rate of positive cultures in presumed aseptic nonunions, (2) the rate and microbial spectrum of positive cultures that represented occult infection, and (3) rates of nonunion healing.
Retrospective cohort study.
Tertiary referral center.
Adult patients with a presumed aseptic nonunion treated with single-stage revision between 2002 and 2022.
The rate of positive cultures compared for 2 protocols: old: 1-2 samples cultured 7 days versus new: 5 samples cultured 14 days. The rate of positive cultures meeting occult infection criteria with the new protocol (≥2 samples with phenotypically indistinguishable microorganisms, or ≥1 sample with a high virulent microorganism). Nonunion healing rates between protocols and between groups based on culture results with the new protocol.
One hundred seventy-nine patients were included. The rate of positive cultures was 14% (n = 15/105) with the old protocol and 51% (n = 38/74) with the new protocol (P < 0.001). With the new protocol, the rate of positive cultures meeting occult infection criteria was 19% (n = 14/74), and coagulase-negative staphylococci (48%) and Cutibacterium acnes (38%) were the most common microorganisms. Nonunion healing rates after the primary revision did not differ between protocols (old: 82% vs. new: 86%, P = 0.41) and groups based on culture result (sterile: 86% vs. occultly infected: 93%, P = 0.66). The final overall nonunion healing rate was 97%.
Occult infections were identified in 1 in 5 presumed aseptic nonunions using a standardized protocol with 5 intraoperative samples cultured 14 days and were predominantly caused by slow growing, gram-positive microorganisms. The local spectrum and antimicrobial sensitivity of occult infections should be considered when developing empiric antimicrobial protocols. Patients with presumed aseptic nonunions can expect high healing rates, regardless of the culture result.
Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.
确定（1）疑似无菌性骨不连的阳性培养率，（2）代表隐性感染的阳性培养率和微生物谱，以及（3）骨不连愈合率。
回顾性队列研究。
三级转诊中心。
2002 年至 2022 年期间接受一期翻修治疗的疑似无菌性骨不连的成年患者。
比较两种方案的阳性培养率：旧方案：1-2 个样本培养 7 天与新方案：5 个样本培养 14 天。新方案中符合隐性感染标准的阳性培养率（≥2 个样本具有表型不可区分的微生物，或≥1 个样本具有高毒力微生物）。基于新方案培养结果的方案之间和组之间的骨不连愈合率。
共纳入 179 例患者。旧方案的阳性培养率为 14%（n=15/105），新方案为 51%（n=38/74）（P<0.001）。使用新方案，符合隐性感染标准的阳性培养率为 19%（n=74/14），凝固酶阴性葡萄球菌（48%）和痤疮丙酸杆菌（38%）是最常见的微生物。初次翻修后，两种方案之间（旧方案：82% vs. 新方案：86%，P=0.41）和基于培养结果的两组之间（无菌组：86% vs. 隐性感染组：93%，P=0.66）的骨不连愈合率无差异。最终总的骨不连愈合率为 97%。
使用标准方案（5 个术中样本培养 14 天），51%的疑似无菌性骨不连可检测到隐性感染，其中主要为生长缓慢的革兰阳性微生物。在制定经验性抗菌方案时，应考虑隐性感染的局部谱和抗菌敏感性。无论培养结果如何，疑似无菌性骨不连患者都有望获得较高的愈合率。
诊断 III 级。请参阅作者说明以获取完整的证据水平描述。
