Abstract
Understanding the nerve distribution within the vastus lateralis muscle in relation to anatomical landmarks is essential for effective botulinum neurotoxin injections to manage chronic anterior knee pain and vastus lateralis muscle tone disorders. This study proposes an anatomically informed approach for administering these injections to the vastus lateralis muscle. Using a modified Sihler’s method, we examined nerve distribution in the vastus lateralis muscles of 12 fresh cadavers. The muscles were analyzed with respect to a transverse line crossing the greater trochanter of the femur and the base of the patella, dividing them into four zones from top to bottom. Ultrasonography was used to examine the muscle anatomy and to guide injections, confirming both structural details and injection accuracy. Intramuscular nerve distribution in the vastus lateralis muscle showed significant patterns, particularly in zones 2 and 3. Based on the nerve distribution and surface landmarks, ultrasonography-guided injections showed high accuracy without damage to surrounding essential anatomical structures. Targeting botulinum neurotoxin injections at the areas with the densest nerve distribution is recommended. Adhering to these guidelines enables clinicians to use minimal doses and reduce the risk of adverse effects such as gait disturbances, antibody production, and bruising from multiple injections.
Data availability
The data are available from the corresponding author upon reasonable request.
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Acknowledgements
This study was conducted in compliance with the principles of the Declaration of Helsinki. Consent was obtained from the families of the deceased patients before beginning the dissection. The authors sincerely thank those who donated their bodies to science for anatomical research. The results of such research can potentially increase the overall knowledge of mankind, which can improve patient care. Therefore, these donors and their families deserve the greatest gratitude.
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All authors have reviewed and approved the article for submission. Conceptualization, Kyu-Ho Yi, Ji-Hyun Lee, Hye-Won Hu Writing—Original Draft Preparation, Kyu-Ho Yi, Hye-Won Hu, Sung-Oh Hwang Writing—Review & Editing, Kyu-Ho Yi, Ji-Hyun Lee, Hyung-Jin Lee Visualization, Hyung-Jin Lee, Hye-Won Hu Supervision, Ji-Hyun Lee, Hyung-Jin Lee.
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I acknowledge that I have considered the conflict of interest statement in the “Author Guidelines.” To the best of my knowledge, I certify that no aspect of my current personal or professional situation might reasonably be expected to significantly affect my views on the subject I am presenting.The authors declare no competing interests.
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All cadavers involved were lawfully donated to the Surgical Anatomy Education Center at the Catholic University of Korea, College of Medicine, following approval by the Institutional Review Board (IRB approval code: Approval No. MC23EISE0022; approval date: March 24, 2023).
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Yi, KH., Hu, H., Hwang, SO. et al. Intramuscular neural distribution of the vastus lateralis informs effective and safe botulinum neurotoxin injection. Sci Rep (2026). https://doi.org/10.1038/s41598-026-37960-7
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DOI: https://doi.org/10.1038/s41598-026-37960-7
