Al-Qattan Mohammad M
Department of Surgery, Division of Plastic Surgery, King Saud University, Riyadh, Saudi Arabia.
J Hand Surg Am. 2010 Nov;35(11):1820-4. doi: 10.1016/j.jhsa.2010.08.011. Epub 2010 Oct 8.
Previous anatomical and clinical studies classified the course of the thenar motor branch of the median nerve into 3 types: the extraligamentous, subligamentous, and transligamentous courses. The presence of a truly preligamentous course has been questioned. Furthermore, there has been recent interest in the presence of a hypertrophic muscle over the transverse carpal ligament (TCL). The current study has 2 aims: to determine the prevalence of the various types of thenar motor branch with particular attention to the existence of the preligamentous type, and to investigate whether the hypertrophic muscle is associated with certain thenar motor branch types.
One hundred consecutive patients undergoing open carpal tunnel releases were studied prospectively. The following data were documented: type of thenar motor branch, presence of hypertrophic muscle over the TCL, and number of thenar branches.
In 100 consecutive patients undergoing open carpal tunnel releases, extraligamentous, subligamentous, transligamentous, and preligamentous types were seen in 56, 34, 9, and 1 patient, respectively. All transligamentous and preligamentous branches were associated with the presence of a hypertrophic muscle over the TCL. Twenty-six of the extraligamentous branches were also associated with the hypertrophic muscle.
The extraligamentous type seems to be the most prevalent thenar motor branch type in most previous studies of various races, including our Middle Eastern population, whereas the preligamentous type is rare. Finally, it is important for the surgeon to know that transligamentous and preligamentous types are associated with the presence of hypertrophic muscle origin over the TCL and that the motor branch will be within this hypertrophic muscle. Incision of this muscle should be done carefully and on the ulnar side to avoid injury to the thenar motor branch.
以往的解剖学和临床研究将正中神经鱼际运动支的走行分为3种类型：韧带外走行、韧带下走行和穿韧带走行。真正的韧带前走行的存在受到了质疑。此外，近来人们对腕横韧带（TCL）上方是否存在肥厚肌肉产生了兴趣。本研究有两个目的：确定各种类型鱼际运动支的发生率，尤其关注韧带前类型的存在情况；研究肥厚肌肉是否与某些鱼际运动支类型相关。
对100例连续接受开放性腕管松解术的患者进行前瞻性研究。记录以下数据：鱼际运动支类型、TCL上方肥厚肌肉的存在情况以及鱼际支的数量。
在100例连续接受开放性腕管松解术的患者中，分别观察到韧带外、韧带下、穿韧带和韧带前类型的患者有56例、34例、9例和1例。所有穿韧带和韧带前分支均与TCL上方肥厚肌肉的存在相关。26例韧带外分支也与肥厚肌肉相关。
在包括我们中东人群在内的以往大多数不同种族的研究中，韧带外类型似乎是最常见的鱼际运动支类型，而韧带前类型则很罕见。最后，外科医生必须了解，穿韧带和韧带前类型与TCL上方肥厚肌肉起点的存在相关，且运动支将位于该肥厚肌肉内。应小心地在尺侧切开此肌肉，以避免损伤鱼际运动支。
