Abstract
Introduction
An accurate and reproducible tibial tunnel placement without danger for the posterior neurovascular structures is a crucial condition for successful arthroscopic reconstruction of the posterior cruciate ligament (PCL). This step is commonly performed under fluoroscopic control. Hypothesis: Performing the tibial tunnel under exclusive arthroscopic control leads to accurate tunnel placement according to recommendations in the literature.
Materials and Methods
Between February 2007 and December 2009, 108 arthroscopic single bundle PCL reconstructions in tibial tunnel technique were performed. The routine postoperative radiographs were screened according to defined quality criterions: 1. Overlap of the medial third of the fibular head by the tibial metaphysis on a-p views 2. Overlap of the dorsal femoral condyles within a range of 4 mm on lateral views 3. X-ray beam parallel to tibial plateau in both views. The radiographs of 48 patients (48 knees) were enrolled in the study. 10 patients had simultaneous ACL reconstruction and 7 had PCL revision surgery. The tibial tunnel was placed under direct arthroscopic control through a posteromedial portal using a standard tibial aming device. Key anatomical landmarks were the exposed tibial insertion of the PCL and the posterior horn of the medial meniscus.
During digital analysis of the postoperative radiographes, the centre of the posterior tibial outlet was determined. On the a-p view, the horizontal distance of this point to the medial tibial spine was measured. The distance to the medial border of the tibial plateau was related to its total width. On the lateral view the vertical tunnel position was measured perpendicularly to a tangent of the medial tibial plateau.
Results
The mean mediolateral tunnel position was 49,3 ± 4,6%, 6,7 ± 3,6 mm lateral to the medial tibial spine. On the lateral view the tunnel centre was 10,1 ± 4,5 mm distal to the bony surface of the medial tibial plateau. Neurovascular damage was observed in none of our patients.
Conclusion
The results of this radiological study confirm that exclusive arthroscopic control for tibial tunnel placement in PCL reconstruction yields reproducible and accurate results according to the literature. Our technique avoids radiation, facilitates the operation room setting and enables the surgeon to visualize the key landmarks for tibial tunnel placement.
