Department of Anesthesia and Pain Management, Toronto Western Hospital, University Health Network,Toronto, Ontario, Canada.
Reg Anesth Pain Med. 2013 May-Jun;38(3):218-25. doi: 10.1097/AAP.0b013e31828db12f.
The macroscopic anatomy of a common paraneural sheath that surrounds the sciatic nerve in the popliteal fossa has been studied recently in a human cadaveric study. It has been suggested that an injection through this sheath could be an ideal location for local anesthetic administration for popliteal block. The aim of the present study was to evaluate the hypothesis that popliteal sciatic nerve blockade through a common paraneural sheath results in shorter onset time when compared with conventional postbifurcation injection external to the paraneural tissue. To illustrate the microscopic anatomy of the paraneural tissues, we performed histological examinations of a human leg specimen.
Following institutional review board approval and written informed consent, 89 patients undergoing an ultrasound-guided popliteal block for foot or ankle surgery were included in the study. They were prospectively randomized to receive a single injection of local anesthetic at the site of bifurcation through a common paraneural sheath (group 1) or 2 separate circumferential injections of the tibial and common peroneal nerves distally to sciatic nerve bifurcation (group 2).
Patients in group 1 had a 30% shorter onset time of both sensory and motor block. This was associated with a more extensive proximal and distal longitudinal spread of local anesthetic in this group. Nerve diameter and cross-sectional area remained unchanged in both groups after injection, which is consistent with extraneural injection. A greater proportion of patients in group 1 required a single needle pass for block performance.
An ultrasound-guided popliteal sciatic nerve block through a common paraneural sheath at the site of sciatic nerve bifurcation is a simple, safe, and highly effective block technique. It results in consistently short onset time, while respecting the integrity of the epineurium and intraneural structures.
最近，在一项人体尸体研究中，对环绕在腘窝坐骨神经周围的常见神经旁鞘的大体解剖结构进行了研究。有人提出，通过该鞘进行注射可能是进行腘窝阻滞的局部麻醉剂的理想位置。本研究的目的是评估通过常见神经旁鞘进行坐骨神经阻滞比在神经旁组织外的常规分叉后注射能更快起效的假设。为了说明神经旁组织的微观解剖结构，我们对人体腿部标本进行了组织学检查。
在获得机构审查委员会批准和书面知情同意后，纳入 89 例接受超声引导下腘窝阻滞以进行足部或踝关节手术的患者参与本研究。他们被前瞻性随机分为两组，一组在分叉处通过常见神经旁鞘单次注射局部麻醉药（组 1），另一组在坐骨神经分叉处的胫神经和腓总神经的远端进行 2 个单独的环形注射（组 2）。
组 1 患者的感觉和运动阻滞的起效时间分别缩短了 30%。这与该组中局部麻醉剂更广泛的近端和远端纵向扩散有关。两组注射后神经直径和横截面积均无变化，这与神经外注射一致。组 1 中有更多的患者需要单次进针来完成阻滞。
在坐骨神经分叉处通过常见神经旁鞘进行超声引导下的腘窝坐骨神经阻滞是一种简单、安全且非常有效的阻滞技术。它始终能实现快速起效，同时保持神经外膜和神经内结构的完整性。
