Shoulder & Elbow Clinic, Department of Orthopaedic Surgery (S.-M.R.), and Department of Radiology (J.S.P.), College of Medicine, Kyung Hee University Hospital, Seoul, Republic of Korea.
Narsha Hospital for Orthopedic Surgery, Busan, Republic of Korea.
J Bone Joint Surg Am. 2020 Aug 5;102(15):1321-1328. doi: 10.2106/JBJS.19.00951.
The purposes of the present study were (1) to create a magnetic resonance imaging (MRI)-based classification system for septic shoulder arthritis and to show the results of arthroscopic debridement based on the classification in eradicating the infection, and (2) to determine the distribution of the Gächter stages, which are determined on the basis of arthroscopic findings only, in each grade of the novel classification system.
The present study included 31 patients who underwent arthroscopic debridement for the treatment of acute septic arthritis of the shoulder between January 2001 and December 2015. The mean duration of follow-up was 2.3 years. The included patients were assessed with use of a novel classification system based on preoperative radiographic and MRI findings. MRI findings were classified as Grade I (only synovitis or joint effusion), Grade II (marrow edema in the bare area of the humeral head), Grade III (cartilaginous erosion), Grade IV (osseous erosion), and Grade V (osseous erosion on MRI also observed on radiographs). No changes on radiographs were observed in Grades I to IV. The intraclass correlation coefficients (ICCs) for interobserver and intraobserver reliability were calculated.
The overall reinfection rate was 54.8% (17 of 31). Among patients with Grade-I, II, III, IV, and V involvement, the reinfection rates were 0 of 4, 1 of 6, 2 of 4, 9 of 12, and 5 of 5, respectively. A diverse distribution of Gächter stages were found in each grade of the novel classification system, with the exception of Grade V. The ICCs for interobserver and intraobserver reliability were 0.81 and 0.80 for the novel classification system. The ICCs for interobserver and intraobserver reliability were 0.75 and 0.78 for Gächter stages.
This novel classification system for the grading of acute shoulder infections on the basis of radiographs and MRI allows preoperative grading of septic arthritis to be performed objectively. Patients who were classified as Grade III or higher in the novel classification system had higher reinfection rates than those who were classified as Grade I or II and required more aggressive treatment to eradicate the infection.
本研究的目的为：（1）建立一种基于磁共振成像（MRI）的脓毒性肩关节炎分类系统，并展示基于该分类行关节镜下清创术治疗感染的疗效；（2）确定仅基于关节镜发现的 Gächter 分期在新型分类系统的各个等级中的分布。
本研究纳入了 2001 年 1 月至 2015 年 12 月期间因急性脓毒性肩关节炎行关节镜下清创术的 31 例患者。平均随访时间为 2.3 年。纳入患者均采用术前影像学和 MRI 检查结果为基础的新型分类系统进行评估。MRI 检查将滑膜炎症或关节积液定义为Ⅰ级，肱骨头裸露区骨髓水肿定义为Ⅱ级，软骨侵蚀定义为Ⅲ级，骨侵蚀定义为Ⅳ级，X 线和 MRI 均观察到骨侵蚀定义为Ⅴ级。Ⅰ至Ⅳ级未见 X 线变化。计算了观察者间和观察者内可靠性的组内相关系数（ICC）。
总体再感染率为 54.8%（31 例中有 17 例）。Ⅰ级、Ⅱ级、Ⅲ级、Ⅳ级和Ⅴ级患者的再感染率分别为 0/4、1/6、2/4、9/12 和 5/5。新型分类系统各等级均存在不同分布的 Gächter 分期，除外Ⅴ级。新型分类系统的观察者间和观察者内可靠性 ICC 分别为 0.81 和 0.80。Gächter 分期的观察者间和观察者内可靠性 ICC 分别为 0.75 和 0.78。
该新型分类系统基于 X 线和 MRI 对急性肩部感染进行分级，可客观地进行脓毒性关节炎的术前分级。新型分类系统分级为Ⅲ级或更高的患者再感染率高于Ⅰ级或Ⅱ级患者，需要更积极的治疗以消灭感染。
