Department of Orthopaedic Surgery, Sungkyunkwan University School of Medicine, Kangbuk Samsung Hospital, Seoul, Korea.
Knee Surg Sports Traumatol Arthrosc. 2011 Apr;19(4):646-52. doi: 10.1007/s00167-010-1326-7. Epub 2010 Dec 11.
The purpose of this study was to investigate the relationship between the proximity of neural structures to standard posterior portals in different knee positions.
Ten fresh cadaveric knees were used to establish the standard posteromedial and posterolateral portals using an outside-in technique with arthroscopic transillumination. The distance from each portal site to the adjacent neurovascular structures (infrapatellar branches of the saphenous nerve) and the sartorial branch of saphenous nerve from the posteromedial portal, and the common peroneal nerve from posterolateral portal was measured using a precision caliper. Distances were recorded with the knees in extension, 45° of flexion and 90° of flexion in order to examine the effect of dynamic knee motion on nerve position.
The mean distance between the posteromedial portal and the superior and inferior branches of infrapatellar branches of the saphenous nerve at full extension was significantly greater than at 90° of flexion. However, there was no difference observed between at 45° and at 90° of flexion. The mean distance from the posteromedial portal to the sartorial branch of saphenous nerve at 90° of flexion was significantly greater (26.1 mm, SD: 4.7) than that at 45° of flexion (18.4 mm, SD: 4.6), and at full extension (14 mm, SD: 4.3) (P < 0.0001). The mean distance between the posterolateral portal to the common peroneal nerve at 90° of flexion was also significantly greater (25.4 mm, SD: 9.2) than that at 45° of flexion (22.5 mm, SD: 8.1), and at full extension (20.1 mm, SD: 9.1) (P < 0.0001).
In this cadaveric study, it shows that position of 90° knee flexion is reasonably safe, in order to establish a posterior portal in knee arthroscopy using the technique described in the current study, especially to avoid the sartorial branch of saphenous nerve and the common peroneal nerve injuries. Results of this study suggest the establishment of posterior portals, while the knee is flexed at an angle of 90° is recommended to ensure the safety of these structures.
本研究旨在探讨不同膝关节位置下神经结构与标准后入路关节镜入路之间的毗邻关系。
使用关节镜透视引导下的经皮入路技术，对 10 例新鲜尸体膝关节建立标准后内侧和后外侧入路。使用精密卡尺测量每个入路点到相邻神经血管结构（隐神经髌下支）和后内侧入路处的隐神经收肌支，以及后外侧入路处的腓总神经之间的距离。记录膝关节伸直、45°和 90°屈曲时的距离，以检查动态膝关节运动对神经位置的影响。
在完全伸直时，后内侧入路与隐神经髌下支的上、下支之间的平均距离明显大于 90°屈曲时的距离。然而，在 45°和 90°屈曲时，两者之间没有差异。在 90°屈曲时，后内侧入路与隐神经收肌支之间的平均距离（26.1mm，SD：4.7）明显大于 45°屈曲时的距离（18.4mm，SD：4.6）和完全伸直时的距离（14mm，SD：4.3）（P<0.0001）。在 90°屈曲时，后外侧入路与腓总神经之间的平均距离（25.4mm，SD：9.2）也明显大于 45°屈曲时的距离（22.5mm，SD：8.1）和完全伸直时的距离（20.1mm，SD：9.1）（P<0.0001）。
在这项尸体研究中，结果表明膝关节 90°屈曲时的位置相对安全，采用本研究中描述的技术在膝关节镜下建立后入路时，尤其是为了避免隐神经髌下支和腓总神经损伤，应避免使用该技术。本研究结果提示，建立后入路时，推荐膝关节弯曲 90°，以确保这些结构的安全。
