Evaluating the risk of popliteal artery injury in the all-inside meniscus repair based on the location of posterior meniscal lesions.

The 'all-inside' meniscus repair is extremely useful technique in addressing tears at the far posterior horn of meniscus. However, this procedure may place the popliteal neurovascular bundle at risk of injury. The purpose of this study was to evaluate the risk of popliteal artery injury by the trajectory of anchor delivery instruments inserted through standard knee arthroscopic portals for the repair of the far posterior horn of meniscus tears. Standard arthroscopic portals were marked on five human cadaveric knees which were subsequently disarticulated. Axial photographs were taken after marking the 5 10, and 15 mm points from the meniscal root on the posterior horns of the menisci. The unsafe zones for meniscus repair at each of these points were identified on the photographs of knees by first drawing two lines from the edges of the popliteal artery and crossing at the respective points at the posterior horns. The points at which these lines meet a circular protractor applied to the center of each meniscus in the knee photograph were recorded as a range. The range signifies the unsafe zone for each respective point on the posterior horn of meniscus. The anterolateral arthroscopic portal fell within the unsafe zone of the 5 mm point on the posterior horn of lateral meniscus in three of the five knees and within the unsafe zone of the 10 mm point on the posterior horn of lateral meniscus in another two knees. A cautious approach should be practiced during the repair of tears located at these two points. None of the other points' unsafe zones (lateral 15 mm, medial 5 mm, 10 mm and 15 mm points) coincided with the ipsilateral portal sites. Level of evidence 5 (Human cadaveric study).