From the Department of Anesthesiology and Pain Medicine, Anesthesia and Pain Research Institute, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul, Korea.
Department of Anesthesiology and Pain Medicine, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Anesth Analg. 2023 Mar 1;136(3):597-604. doi: 10.1213/ANE.0000000000006364. Epub 2023 Feb 17.
The pericapsular nerve group (PENG) block was recently suggested as a regional technique for managing acute pain after hip surgery. However, few anatomical studies have confirmed the spread of injectate during the PENG block. This cadaver study aimed to analyze injectate spread to the target nerves during single-injection ultrasound-guided PENG block.
Ultrasound-guided PENG block with 3 different injectate volumes (10, 20, or 30 mL) was performed in 18 cadavers. Injectate spread by the volume was first evaluated on computed tomography, followed by cadaver dissection. The spread of the dye over the pelvis and lower limb was evaluated.
The articular branches of the femoral nerve were stained nearly sufficiently with 20- and 30-mL specimens. The femoral nerve itself was stained simultaneously in six of 12 (50%) 20-mL specimens and 12 of 12 (100%) 30-mL specimens. The accessory obturator nerve was observed only in three (9%) of 36 specimens. The articular branches of the obturator nerve were rarely affected, regardless of injectate volume (1/12, 10 mL specimens; 2/12, 20 mL specimens; 1/12, 30 mL specimens; P > .999). Rather, the obturator nerve was affected. However, the obturator nerve was not stained consistently even with 30 mL of injectate (50%).
After combining the dissection and radiological findings, the single-injection ultrasound-guided PENG blocks with volumes of 10, 20, and 30 mL do not support motor sparing or selective anterior hip capsule innervation in a clinical setting. If early rehabilitation is needed, high-volume PENG block might not be the ideal option, and persisting pain after PENG block might be attributed in part to the lack of obturator nerve articular branches blockade.
囊周神经群（PENG）阻滞术最近被提出作为髋关节手术后急性疼痛管理的一种区域技术。然而，很少有解剖学研究证实 PENG 阻滞术中注射剂的扩散。这项尸体研究旨在分析单次超声引导 PENG 阻滞时注射剂向目标神经的扩散。
在 18 具尸体中进行了超声引导的 PENG 阻滞，使用了 3 种不同的注射量（10、20 或 30 mL）。首先在计算机断层扫描上评估注射量引起的扩散，然后进行尸体解剖。评估染料在骨盆和下肢的扩散情况。
股神经的关节支在 20-和 30-mL 标本中几乎能被充分染色。股神经本身在 12 个 20-mL 标本中的 6 个（50%）和 12 个 30-mL 标本中（100%）同时被染色。辅助闭孔神经仅在 36 个标本中的 3 个（9%）中观察到。闭孔神经的关节支无论注射量如何，都很少受到影响（1/12，10-mL 标本；2/12，20-mL 标本；1/12，30-mL 标本；P＞.999）。相反，闭孔神经受到了影响。然而，即使使用 30 mL 的注射剂，闭孔神经也不能被一致染色（50%）。
综合解剖和影像学发现，单次注射超声引导 PENG 阻滞，无论使用 10、20 或 30 mL 的容量，都不能在临床环境中支持运动神经保留或选择性髋关节前囊神经支配。如果需要早期康复，高容量的 PENG 阻滞可能不是理想的选择，PENG 阻滞后持续疼痛部分归因于缺乏闭孔神经关节支阻滞。
