The Effects of Trans-Tibial versus Anteromedial Portal Technique on the Stress Patterns around the Femoral Tunnel in Anatomical Single-Bundle ACL Reconstruction Using a Finite Element Analysis (SS-68)

2012 ◽  
Vol 28 (6) ◽  
pp. e35-e36
Author(s):  
Young-jin Seo ◽  
Yon-sik Yoo ◽  
Si young Song ◽  
Hak jin Kim ◽  
Heon young Kim
2014 ◽  
Vol 2 (11_suppl3) ◽  
pp. 2325967114S0012
Author(s):  
Cem Coşkun Avcı ◽  
Hüseyin Koca ◽  
Necdet Sağlam ◽  
Tuhan Kurtulmuş ◽  
Gürsel Saka

Objectives: Recent studies have demonstrated that ACL reconstruction via anatomic tunnel placement would provide superior stability. In order to achieve an anatomic femoral tunnel, accessory anteromedial portal (three-portal tecnique) and medial Hoffa excision is necessary. Femoral tunnel drilling through a far anteromedial portal facilitates anatomic tunnel placement but can also results in shorter femoral tunnel and articular cartilage damage of the medial femoral condyle. Our purpose in this study was to evaluate whether an anatomic single bundle ACL reconstruction can be performed with the use of the two standart portals (anteromedial and anterolateral). Methods: Fifty seven patient underwent single bundle ACL reconstruction in our clinic between 2012-2014, with the use of either standart portals or three-portal tecnique. We measured the tunnel length and and femoral tunnel angle in coronal plane to assess the reconstruction. Two portals group included thirty -three patients (twenty-nine males, four females with a mean age of 27±2,4) and three portals group included twenty–four patients (twenty-three males, one female with a mean age of 26±2,9). All patients were evaluated with computerized tomography (CT) scans to determine femoral tunnel length and obliquity. Tunnel length was defined as the distance between the intra-articular and extra-articular tunnel apertures in coronal sections. Femoral tunnel angle was measured in the coronal plane on AP radiographs of the knee. For statistical analysis, student t test was used for normal categorical data. A p value of <0.05 was considered significant. Results: Average tunnel length was 44.2 ±6.8 mm (range: 32.6-55.2) in two portals group and 32.8±7.9 mm (range: 24.8-43.2) in three portal group. The average tunnel length in three portal group was significantly smaller (p<0.05). According to radiographic measurement on the AP view, femoral tunnel angle averaged 48.20±7.10 (range:38.60-56.10) in two portals group and 47.20±6,30 (range: 39.40-55.20) in three portals group. This difference was not statistically significant (p=0.2). Conclusion: Femoral tunnels drilled with standart two-portal tecnique were longer than three-portal tecnique. However, femoral tunnel angles was not different in two groups. Tunnel characteristic in terms of anatomic position was obtained with standart two-portal tecnique. Consequently, femoral tunnels can be placed anatomically with standart portals.


2021 ◽  
Vol 9 (4) ◽  
pp. 232596712110018
Author(s):  
Sung-Jae Kim ◽  
Si Young Song ◽  
Tae Soung Kim ◽  
Yoon Sang Kim ◽  
Seong-Wook Jang ◽  
...  

Background: It remains unclear whether an anteromedial (AM) footprint or a central footprint anterior cruciate ligament (ACL) graft exhibits less contact stress with the femoral tunnel aperture. This contact stress can generate graft attrition forces, which can lead to potential graft failure. Purpose/Hypothesis: The purpose of this study was to compare the difference in contact stress patterns of the graft around a femoral tunnel that is created at the anatomic AM footprint versus the central footprint. It was hypothesized that the difference in femoral tunnel positions would influence the contact stress at the interface between the reconstructed graft and the femoral tunnel orifice. Study Design: Controlled laboratory study. Methods: A total of 24 patients who underwent anatomic single-bundle ACL reconstruction were included in this study. In 12 patients, the femoral tunnels were created at the center of the native AM footprint (AM group), and in the remaining 12 patients the center of the femoral tunnel was placed in the anatomic central footprint (central group). Three-dimensional knee models were created and manipulated using several modeling programs, and the graft-tunnel angle (GTA) was determined using a special software program. The peak contact stresses generated on the virtual ACL graft around the femoral tunnel orifice were calculated using a finite element method. Results: The mean GTA was significantly more obtuse in the AM group than in the central group (124.2° ± 5.9° vs 112.6° ± 7.9°; P = .001). In general, both groups showed high stress distribution on the anterior surface of the graft, which came in contact with the anterior aspect of the femoral tunnel aperture. The degree of stress in the central group (5.3 ± 2.6 MPa) was significantly higher than that in the AM group (1.2 ± 1.1 MPa) ( P < .001). Conclusion: Compared with the AM footprint ACL graft, the central footprint ACL graft developed significantly higher contact stress in the extended position, especially around the anterior aspect of the femoral tunnel orifice. Clinical Relevance: The contact stress of the ACL graft at the extended position of the knee may be minimized by creating the femoral tunnel at the AM-oriented footprint.


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