Department of Anatomy, School of Medicine, Konkuk University, Chungju, Korea.
Division in Anatomy and Developmental Biology, Department of Oral Biology, Human Identification Research Institute, BK21 FOUR Project, Yonsei University College of Dentistry, Seoul, Korea.
Surg Radiol Anat. 2024 Sep;46(9):1543-1548. doi: 10.1007/s00276-024-03440-8. Epub 2024 Jul 16.
The anterior belly of the digastric muscle (ABDM) is the target of botulinum toxin injection; however, anatomical considerations related to the injection point are absent. This study used Sihler's staining to analyze the intramuscular nerve distribution of ABDM to identify the most effective botulinum toxin injection points.
We used 12 specimens from 6 embalmed cadavers in this study. The specimens were manually dissected to preserve the mylohyoid nerve and subjected to Sihler's staining. From the gnathion to and hyoid bone, the ABDM was divided into three equal parts, distinguishing the anterior, middle, and posterior thirds.
Only a branch of the mylohyoid nerve entered the ABDM, and its entry point was located in the middle-third region in all cases. The nerve endings were concentrated in the middle third (100%), followed by the anterior third (58.3%) and were not observed in the posterior third.
The landmarks used in this study (gnathion and hyoid bone) are easily palpable on the skin surface, allowing clinicians to target the most effective injection site (middle third of ABDM). These results provide scientific and anatomic evidence for injection points, and will aid in the management of ABDM injection procedures in clinical practice.
二腹肌前腹（ABDM）是肉毒毒素注射的目标；然而，关于注射点的解剖学考虑因素是缺失的。本研究使用 Sihler 染色来分析 ABDM 的肌内神经分布，以确定最有效的肉毒毒素注射点。
我们在这项研究中使用了 6 具防腐尸体的 12 个标本。这些标本经过手动解剖以保留下颌舌骨神经，并进行 Sihler 染色。从颌下点到舌骨，ABDM 被分为三个相等的部分，区分前三分之一、中三分之一和后三分之一。
只有下颌舌骨神经的一个分支进入 ABDM，在所有情况下，其进入点都位于中三分之一区域。神经末梢集中在中三分之一（100%），其次是前三分之一（58.3%），在后三分之一中没有观察到。
本研究中使用的标志点（颌下点和舌骨）在皮肤表面很容易摸到，使临床医生能够定位最有效的注射部位（ABDM 的中三分之一）。这些结果为注射点提供了科学和解剖学证据，并将有助于临床实践中 ABDM 注射程序的管理。
