前交叉韧带重建术后关节感染与粘连的MRI征象

MRI findings of joint infection and adhesion after anterior cruciate ligament reconstruction

目的分析前交叉韧带(ACL)重建术后所致滑膜增厚的关节病变,比较关节感染与粘连的MRI征象差异。方法回顾性分析25例ACL重建术后滑膜增厚患者临床及MRI资料,诊断均经关节镜等检查证实,其中11例关节感染,14例关节粘连,与首次关节镜下ACL重建术的时间间隔分别为0.3~2.5个月、6~19个月。结果 MRI滑膜增厚病变分别为关节感染和关节粘连。关节感染MRI征象除滑膜增厚外,还可见关节中至大量积液、软组织不同程度肿胀、股骨远端及胫骨近端骨髓水肿、ACL假体纤维连续(5例表现为信号增高)以及骨道假性增宽(5例)。术后关节粘连MRI征象除滑膜增厚外,还可见部分增厚滑膜内见条带状短T2信号,主要累及髌上囊、内外侧隐窝、髌下脂肪垫、髁间窝等部位,关节无或仅见少量积液,ACL假体均连续,3例表现为假体信号增高、边缘毛糙,骨道均无明显增宽。在关节感染与关节粘连间,关节积液、软组织肿胀、骨髓水肿、骨道假性增宽各征象差异有统计学意义(P均<0.05)。结论关节感染主要表现为滑膜增厚、关节积液,关节腔呈高信号,而关节粘连表现为滑膜增厚、关节腔呈等/稍高信号;关节感染主要发生于术后早期,关节粘连主要发生于术后中晚期。

Objective To analyze the joint lesions of synovial thickening after anterior cruciate ligament（ACL）reconstruction,and to explore the differences of MRI findings between joint infection and adhesion.Methods Clinical and MRI data of 25 patients with synovial thickening（11 with infections and 14 with adhesion）confirmed by arthroscopy were retrospectively analyzed.The time interval from first ACL reconstruction to the arthroscopy after ACL was 0.3—2.5（mean[1.1±0.6]）months and 6.0—19.0（mean[11.0±4.9]）months,respectively.Results The lesions caused synovial thickening on MRI included joint infection and joint adhesion.MRI findings of joint infection included synovial thickening,moderate to massive joint effusion,different degrees of soft tissue swelling,bone marrow edema of distal femur and proximal tibia,ACL graft continuous fiber（high signals in 5 patients）and bone tunnel pseudo widened in 5 patients,while of joint adhesion included synovial thickening,striped short T2 signals in part of the thickened synovium on suprapatellar bursa,medial and lateral recess,the infrapatellar fat pad and the intercondylar fossa,without or only a small amount of joint effusion,ACL graft continuous,as well as high signals and rough edge in 3 patients,while bone tunnel was not significantly widened.Statistical differences of joint effusion,soft tissue swelling,edema of bone marrow and bone tunnel pseudo widened were found between joint infection and joint adhesion（all P〈0.05）.Conclusion MRI findings of joint infection mainly included synovial thickening,joint effusion and high signal of joint cavity,while of joint adhesion were synovial thickening,equal or slightly high signal of joint cavity.Joint infections mainly occurred in the early stage after operation,while joint adhesions mainly occurred in the middle and late stage after operation.