Kongcharoensombat W, Charoensri P
Department of Orthopaedics, Lerdsin Hospital, Bangkok, Thailand.
Department of Orthopaedics, Sunpasitthiprasong Hospital, Ubon Ratchathani, Thailand.
Malays Orthop J. 2023 Jul;17(2):57-61. doi: 10.5704/MOJ.2307.009.
The infrapatellar branch of saphenous nerve (IPBSN) has anatomic variations and prone to injury during surgery around the medial side of the knee. High tibial osteotomy is one of the procedures that may be risky to the IPBSN. This research was aimed to establish which skin incision (vertical vs oblique) is less likely to damage to the IPBSN and also to study the anatomy of the IPBSN, with the institutional review board reference (No. LH611054, date 10/1/2020). The primary outcomes are aimed to establish which skin incision (vertical vs oblique) is less damaging to the IPBSN. The secondary outcome is to study about the anatomy of the IPBSN.
Twenty-two fresh cadavers (forty-four knees) were dissected by randomisation under the block of four technique, and two different incisions were performed for each knee. Exploration was performed from the skin incision to the IPBSN around the incision zone. If the discontinuity of the nerve was found, it was classified as IPBSN injury. The anatomic measurement was performed. The IPBSN injury between two groups were analysed with the chi-square test.
The risk of IPBSN injury in the oblique group was 2 from 22 knees (9.1%), and 12 knees from 22 knees (54.5%) in the vertical group (P=0.001). Most common number of branch(es) found, is one branch, the horizontal distance ranged from 2.6cm to 8.5cm (average 5.7±1.6), the vertical distance ranged from 4.4cm to 12.6cm (average 7.6±1.9) and the declination angle ranged from 6° to 87° (average 34.7±24.3).
The risk of the IPBSN injury in oblique skin incision may be less than the vertical incision in the medial opening wedge HTO.
隐神经髌下支（IPBSN）存在解剖变异，在膝关节内侧周围手术时容易受损。高位胫骨截骨术是可能对IPBSN有风险的手术之一。本研究旨在确定哪种皮肤切口（垂直切口与斜切口）对IPBSN的损伤可能性较小，并研究IPBSN的解剖结构，参考机构审查委员会（编号LH611054，日期2020年10月1日）。主要结果旨在确定哪种皮肤切口（垂直切口与斜切口）对IPBSN的损伤较小。次要结果是研究IPBSN的解剖结构。
22具新鲜尸体（44个膝关节）在四种技术分组下随机解剖，每个膝关节进行两种不同的切口。从皮肤切口向切口周围的IPBSN进行探查。如果发现神经连续性中断，则分类为IPBSN损伤。进行解剖测量。两组之间的IPBSN损伤采用卡方检验进行分析。
斜切口组22个膝关节中有2个发生IPBSN损伤（9.1%），垂直切口组22个膝关节中有12个发生损伤（54.5%）（P=0.001）。发现的分支最常见数量为1支，水平距离为2.6厘米至8.5厘米（平均5.7±1.6），垂直距离为4.4厘米至12.6厘米（平均7.6±1.9），偏斜角度为6°至87°（平均34.7±24.3）。
在内侧开放楔形高位胫骨截骨术中，斜皮肤切口导致IPBSN损伤的风险可能低于垂直切口。
