Waelti Stephan L, Wildermuth Simon, Willems Erik P, Fischer Tim, Dietrich Tobias J, Leschka Sebastian, Matissek Christoph, Krebs Thomas, Markart Stefan
Department of Radiology and Nuclear Medicine, Children's Hospital of Eastern Switzerland, 9006 St. Gallen, Switzerland.
Department of Radiology and Nuclear Medicine, Cantonal Hospital St. Gallen, 9007 St. Gallen, Switzerland.
J Clin Med. 2023 Apr 21;12(8):3016. doi: 10.3390/jcm12083016.
The resorption of magnesium-based alloy bioabsorbable screws results in the release of hydrogen gas, which can mimic infection and enter the growth plate. The screw itself and the released gas may also affect image quality.
The evaluation of magnetic resonance imaging (MRI) findings during the most active phase of screw resorption is the objective, with particular focus on the growth plate and to assess for the presence of metal-induced artifacts.
In total, 30 prospectively acquired MRIs from 17 pediatric patients with fractures treated with magnesium screws were assessed for the presence and distribution of intraosseous, extraosseous, and intra-articular gas; gas within the growth plate; osteolysis along the screw; joint effusion; bone marrow edema; periosteal reaction; soft tissue edema; and metal-induced artifacts.
Gas locules were found in the bone and soft tissues in 100% of the examinations, intra-articular in 40%, and in 37% of unfused growth plates. Osteolysis and the periosteal reaction were present in 87%, bone marrow edema in 100%, soft tissue edema in 100%, and joint effusion in 50% of examinations. Pile-up artifacts were present in 100%, and geometric distortion in 0% of examinations. Fat suppression was not significantly impaired in any examination.
Gas and edema in the bone and soft tissues are normal findings during the resorption of magnesium screws and should not be misinterpreted as infection. Gas can also be detected within growth plates. MRI examinations can be performed without metal artifact reduction sequences. Standard fat suppression techniques are not significantly affected.
镁基合金生物可吸收螺钉的吸收会导致氢气释放，这可能会模拟感染并进入生长板。螺钉本身和释放的气体也可能影响图像质量。
评估螺钉吸收最活跃阶段的磁共振成像（MRI）表现，特别关注生长板，并评估是否存在金属诱导伪影。
对17例接受镁螺钉治疗骨折的儿科患者前瞻性采集的30份MRI进行评估，以确定骨内、骨外和关节内气体的存在及分布；生长板内的气体；沿螺钉的骨质溶解；关节积液；骨髓水肿；骨膜反应；软组织水肿；以及金属诱导伪影。
100%的检查在骨和软组织中发现气体小腔，40%在关节内，37%在未融合的生长板中。87%的检查存在骨质溶解和骨膜反应，100%存在骨髓水肿，100%存在软组织水肿，50%存在关节积液。100%的检查存在堆积伪影，0%存在几何变形。在任何检查中脂肪抑制均未受到明显损害。
镁螺钉吸收过程中骨和软组织中的气体及水肿是正常表现，不应被误解为感染。生长板内也可检测到气体。MRI检查无需使用金属伪影减少序列即可进行。标准脂肪抑制技术未受到明显影响。
