Select a Community
Are you sure you want to trigger topic in your Anconeus AI algorithm?
You are done for today with this topic.
Would you like to start learning session with this topic items scheduled for future?
Center of tibia tunnel placement in-line with the posterior aspect of the anterior horn of the lateral meniscus
4%
70/1773
Horizontal femoral tunnel placement (10 or 2 o’clock position)
8%
143/1773
Femoral tunnel placement anterior to the lateral intercondylar ridge
73%
1298/1773
One-incision instead of two-incision tunnel drilling technique
6%
112/1773
Tibial tunnel is parallel and posterior to Blumenstaat's line when knee is fully extended
139/1773
Select Answer to see Preferred Response
Tunnel placement has a crictical role in clinical outcomes. AAOS COR review book states "The most common error in an ACL reconstruction is to place either the tibial or femoral tunnel too anteriorly, leading to graft impingement and failure." The text also states that graft type and the number of incisions do not appear to affect outcome. It is important to note that initial graft tension decreases shortly after the anterior cruciate ligament graft is retrieved. The article by van Kampen et al was a prospective study looking at 38 patients treated with bone patella bone autografts with interference screws and the tibial block secured at 20 degrees of flexion. The patients were split into two groups: One group was tensioned at 20N, the other at 40N. They found no clinically significant difference in stability in these two patient groups one year out and thus graft tensioning does not appear to be as important as graft tunnel placement. Miller's review states "Significant controversy exists regarding the double-bundle ACL reconstruction" and the literature has not shown a definitive clinical outcome benefit compared to single bundle reconstruction. Kopf et al provides a 3D CT model to provide the following illustrations and discussion on ACL tunnel placement. Illustration A shows orientation of the AM and PL bundle insertions is well demonstrated. When the knee is in extension (0°), the ACL insertion is nearly vertical with the AM insertion proximal to the PL insertion. When the knee is in flexion (90°), the ACL insertion is nearly horizontal. Illustration B shows that the lateral intercondylar and bifurcate ridges are visualized arthroscopically and by 3D CT. The area anterior the AM and PL insertions is outlined (circular dots) to demonstrate that the entire femoral ACL insertion lies posterior to the lateral intercondylar ridge on the medial wall of the lateral femoral condyle. Illustration C demonstrates a timeline of ACL reconstruction techniques and compares their associated tunnel placements to the native ACL footprint.
4.3
(17)
Please Login to add comment