Background:

Despite successful anterior cruciate ligament (ACL) reconstruction, many patients continue to experience persistent anterolateral rotatory instability. Lateral extra-articular tenodesis (LET) is used to address this instability by harvesting a portion of the iliotibial band, passing it underneath the fibular collateral ligament, and attaching it just proximal and posterior to the lateral femoral epicondyle. Based on the most recent clinical evidence, the addition of LET to ACL reconstruction improves clinical outcomes, which has led to an increase in the use of this technique.

Purpose:

To provide an overview of the postoperative complications of the LET procedure and their associated imaging findings, with a focus on magnetic resonance imaging (MRI).

Study Design:

Narrative review.

Methods:

In this scoping review, the authors reviewed available radiographic, computed tomography, and MRI scans of patients who experienced postoperative complications after ACL reconstruction with LET, in which the complication was determined to be from the LET procedure. Images were reviewed and subsequently described by an on-staff musculoskeletal radiologist.

Results:

The authors found 9 different complications associated with LET: graft failure, hematoma, infection, chronic pain, tunnel convergence, fixation device migration, muscular hernia, peroneal nerve palsy, and knee stiffness. They supplemented these findings with radiographic evidence from 6 patients.

Conclusion:

As extra-articular reconstruction techniques including LET become more popular among orthopaedic surgeons, it is important that radiologists and surgeons be adept at recognizing the normal imaging findings of LET and associated complications.

中文翻译：

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膝关节外侧关节外肌腱固定术后并发症的影像学发现：当前概念回顾

背景：

尽管前交叉韧带 (ACL) 重建成功，但许多患者继续经历持续的前外侧旋转不稳定。外侧关节外肌腱固定术 (LET) 用于解决这种不稳定性，方法是采集髂胫束的一部分，将其穿过腓侧副韧带下方，并将其连接到股骨外侧上髁的近端和后部。根据最新的临床证据，在 ACL 重建中添加 LET 可改善临床结果，从而导致该技术的使用增加。

目的：

概述 LET 手术的术后并发症及其相关影像学表现，重点是磁共振成像 (MRI)。

学习规划：

叙述审查。

方法：

在本次范围审查中，作者回顾了 LET 重建 ACL 后出现术后并发症的患者的可用 X 线片、计算机断层扫描和 MRI 扫描，其中确定并发症来自 LET 手术。图像由在职的肌肉骨骼放射科医师审查并随后描述。

结果：

作者发现了与 LET 相关的 9 种不同并发症：移植失败、血肿、感染、慢性疼痛、隧道会聚、固定装置移位、肌肉疝、腓神经麻痹和膝关节僵硬。他们用 6 名患者的影像学证据补充了这些发现。

结论：

随着包括 LET 在内的关节外重建技术在骨科医生中越来越流行，放射科医生和外科医生必须善于识别 LET 的正常影像学表现和相关并发症。