Department of Anatomy, All India Institute of Medical Sciences, Phulwarisharif, Patna, India.
Department of Anatomy, Jagiellonian University, Krakow, Poland.
Folia Morphol (Warsz). 2023;82(2):231-241. doi: 10.5603/FM.a2022.0042. Epub 2022 Apr 28.
Considerable variations have been reported regarding the branching pattern of tibial nerve (TN) close to its termination in foot. In order to comprehend the clinical anatomy of heel pain awareness of all the possible variations in relation to terminal branching pattern of TN (close to the tarsal tunnel) is essential. The present study was conducted to undertake a comprehensive review of the variations in TN branches in foot with particular emphasis on the implications for sensory distribution of these branches. Articles were searched in major online indexed databases using relevant key words. The pattern of termination of TN was noted as either trifurcation or bifurcation. Bifurcation pattern was more commonly observed and is associated with the medial calcaneal nerve (MCN) either arising high or low relative to the tarsal tunnel. The most commonly noted type of bifurcation was proximal to malleolar-calcaneal axis but within the tarsal tunnel. Across all five types of bifurcation reported in literature, the termination points of TN ranged from 3 cm proximal to 3 cm distal to malleolar-calcaneal axis and, therefore, the area beyond this region can be considered as safe zone for performing invasive procedures. MCN showed considerable variations in its origin both in trifurcation and bifurcation pattern pertaining to number of branches (one/two/three) at the point of origin. The origin of inferior calcaneal nerve was observed to be relativelyless variable as it mostly arose as a branch of lateral plantar nerve and sometimes as a direct branch from TN before termination. The frequent variation of MCN in the tarsal tunnel should be kept in mind while undertaking decompression measures in medial ankle region.
在靠近足部的胫骨神经 (TN) 分支模式方面，已经有相当多的报道。为了理解足跟疼痛的临床解剖学，了解 TN 终末分支模式（靠近跗管）的所有可能变异是必不可少的。本研究旨在对足部 TN 分支的变异进行全面综述，特别强调这些分支的感觉分布的意义。使用相关关键词在主要在线索引数据库中搜索文章。TN 的终止模式被记录为三分叉或二分叉。二分叉模式更为常见，与内侧跟骨神经（MCN）有关，无论是在跗管上方还是下方起源。最常见的分叉类型是在距骨-跟骨轴的近端，但在跗管内。在文献中报道的所有五种类型的分叉中，TN 的终止点范围从距骨-跟骨轴近端 3 厘米到远端 3 厘米，因此，该区域以外的区域可以被视为进行侵入性手术的安全区域。MCN 在其起源方面表现出相当大的变异，无论是在三分叉还是二分叉模式中，其起源点的分支数量（一/二/三）都有所不同。观察到跟骨下神经的起源相对较少变化，因为它主要作为足底外侧神经的分支出现，有时在终止前直接作为 TN 的分支出现。在进行内踝区域减压措施时，应注意 MCN 在跗管中的频繁变异。
