Imaging Findings of Complications After Lateral Extra-Articular Tenodesis of the Knee: A Current Concepts Review

Abstract

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.

Keywords: LET; MRI; anterolateral rotatory instability; complications; lateral extra-articular tenodesis.

Figure 1.

The anatomy of the anterolateral structures of the knee. ALL, anterolateral ligament; FCL, fibular collateral ligament; GT, lateral head of the gastrocnemius; ITB, iliotibial band; LE, lateral epicondyle; PLT, popliteus tendon.

Figure 2.

Proton density–weighted magnetic resonance imaging (MRI) appearance of normal anterolateral ligament (ALL) and related lateral structures. (A) Axial sequence demonstrating the inferior lateral genicular arteries (arrow), the ALL (arrowhead), the fibular collateral ligament (notched arrow), and the biceps femoris (pentagon arrow). (B) On a coronal MRI sequence, the ALL is identified (arrow). (C) Axial and (D) coronal sequences identifying the proximal Kaplan fibers (arrows) extending from the femur to the iliotibial band.

Figure 3.

(A) Illustration of lateral extra-articular tenodesis using the modified Lemaire procedure. The midsubstance strip of the iliotibial band is seen coursing deep to the posterior cruciate ligament. (B) Pre- and postoperative radiographs obtained in a 14-year-old patient who underwent revision anterior cruciate ligament reconstruction via the transosseous tunnel technique with modified Lemaire lateral extra-articular tenodesis (LET) and lateral meniscal root repair. (C) Intraoperative images of the modified Lemaire LET procedure.

Figure 4.

(A) Axial proton-density fast-spin sequences from distal to proximal demonstrating the normal magnetic resonance imaging appearance of the modified Lemaire lateral extra-articular tenodesis procedure. Images show the graft (arrows) extending from the Gerdy tubercle in the proximal tibia to the lateral femoral condyle. Note the defect in the iliotibial band secondary to graft harvesting (arrowheads). (B) Coronal proton-density fast-spin sequences from distal to proximal demonstrating the iliotibial band (arrows) extending from the proximal tibia to the lateral femoral condyle.

Figure 5.

Pre- and postoperative radiographs obtained in a patient who underwent revision anterior cruciate ligament (ACL) reconstruction with lateral extra-articular tenodesis (LET). (A) Preoperatively, the patient reported anterior lateral rotary instability due to double-bundle ACL graft failure, which is illustrated via anterior subluxation of the tibia on a lateral radiograph (asymmetric bracket). (B) After revision ACL reconstruction with LET secured using a staple, reduction of prior anterior tibial translation was obtained (symmetric bracket).

Figure 6.

(A) Coronal and (B) sagittal proton-density fat-saturated magnetic resonance imaging sequences demonstrate full-thickness tear of the lateral extra-articular tenodesis at the femur (regular arrow), with concomitant anterior cruciate ligament (ACL) graft failure seen on the sagittal sequence (pentagon arrow in images A and B). Arrowhead in panel A delineates the ACL femoral tunnel on the coronal sequence. There is concomitant medial meniscal peripheral vertical tear with extrusion of the body into the medial gutter (notched arrow).

Figure 7.

(A) Coronal and (B) axial proton-density fat-saturated magnetic resonance imaging sequences demonstrate a partial-thickness tear of the lateral extra-articular tenodesis graft proximally at the femoral attachment (arrows), as well as anterior cruciate ligament graft failure (arrowheads).

Figure 8.

Postoperative magnetic resonance imaging scans demonstrating a hematoma secondary to a lateral inferior genicular artery injury from graft harvesting. (A) Sagittal T2-weighted proton-density fast-spin (B) axial and (C) coronal sequences demonstrate a hematoma (arrows) extending from lateral to the vastus lateralis down to the level of the insertion of the iliotibial band, insinuating into the surgical defect at the graft donor site (arrowheads). Proton-density (D) axial and (E) coronal sequences demonstrate the normal anatomy of the lateral inferior genicular artery (pentagon arrows). (F and G) Illustrations demonstrating the blood supply of the knee are provided for reference. A, artery.

Figure 9.

(A) Axial and (B) coronal proton-density magnetic resonance imaging sequences demonstrate soft edema surrounding the iliotibial (IT) band (arrows) consistent with cellulitis and deep tissue infection involving the IT band and an associated prepatellar abscess (arrowhead).

Figure 10.

Anteroposterior radiographs of a combined tibial intramedullary nail and lateral extra-articular tenodesis procedure with staple fixation at (A) 1 month and (B) 3 months postoperatively. Staple pullout at the lateral femoral epicondyle proximal fixation site is seen in panel B.

Figure 11.

Postoperative coronal proton-density magnetic resonance imaging scan demonstrates diffuse low–signal intensity scarring (arrowheads) involving the iliotibial band (arrows) and its Kaplan fibers along the anterolateral aspect of the proximal femur in this patient with arthrofibrosis that resulted in persistent knee stiffness after a lateral extra-articular tenodesis procedure.

Figure 12

Multiligament reconstruction seen on (A and B) anteroposterior radiographs and (C) coronal and (D) axial computed tomography images. The pentagon arrows indicate the posterior cruciate ligament reconstruction tunnel, arrowheads indicate a chronic Pellegrini-Stieda lesion from a prior medial collateral ligament injury, and thin black arrows indicate the site of the tunnel for lateral extra-articular tenodesis (LET) and the anterior cruciate ligament (ACL) reconstruction. In panel B, tunnel positions are indicated for the LET tunnel (green rectangle) and for the femoral tunnel of the ACL reconstruction (orange rectangle).

Figure 13.

(A) Lateral radiograph and (B) non–fast spin proton-density sagittal magnetic resonance imaging scans demonstrating an ideal isometric femoral lateral extra-articular tenodesis graft attachment site and femoral tunnel position (red ellipses) located between the lateral femoral epicondyle (triangle) and Kaplan fiber attachment (square) point on the femur. Images adapted from Jaecker et al and Slette et al.

Figure 14.

Proton-density axial magnetic resonance imaging scans demonstrate lateral herniation of the vastus lateralis muscle (arrows) due to harvesting of the iliotibial band graft too anteriorly.

Figure 15.

Proton-density axial magnetic resonance imaging sequence demonstrating edema within and surrounding an enlarged common peroneal nerve (arrows). Excessive traction on the nerve intraoperatively resulted in a temporary peroneal nerve palsy.