The relationship of neurovascular structures to the posterior medial aspect of the knee: an anatomic study using plastinated cross-sections.

The purpose of this study was to evaluate the topography of the saphenous nerve branches and of the popliteal neurovascular bundle of knee and to establish a low risk placement position of the posteromedial knee portal (PmKP). A slice anatomy study, by using plastinated transparent knee cross-sections was performed on 12 intact right male cadaver lower limbs. The measurements were performed at the level of the medial epicondyle (MEc), at the joint line level and at the level of the tibial attachment of the posterior cruciate ligament (PCL). The popliteal artery (PA) is predicted to be 8.66±2.17 mm dorsal and the sartorial branch of the saphenous nerve (SBSN) at 4.27±0.05 mm posterior to the joint capsule at the level of the MEc. At the joint level, the PA is 7.86±2.26 mm away from the PCL and the SBSN is predicted at 2.41±0.12 mm posterior to the joint capsule. At the level of the tibial attachment of the PCL, the PA to PCL the distance is 5.93±3.61 mm and the SBSN is situated at 4.36±0.43 mm posterior to the joint capsule. Based on our anatomic data, a PmKP placed at the level of the MEc appears to be safe, effective, and reproducible. At the level of MEc, the PA is situated widely lateral to the MEc and the distance between the saphenous nerve branches and the articular capsule is greater than on the other levels. This study suggests that by placing the PmKP at the level of MEc, the risk of neurovascular injuries could be reduced.