Related Experiment Video
Updated: Jul 18, 2025

Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
Intramuscular Neural Distribution of Adductor Pollicis Muscle Spasticity in Cadaver Model Regarding Botulinum
Kyu-Ho Yi1,2, Kang-Woo Lee1, Yousun Hwang3
1Division in Anatomy and Developmental Biology, Department of Oral Biology, Human Identification Research Institute, BK21 FOUR Project, Yonsei University College of Dentistry, Seoul, Korea.
Purpose:
The adductor pollicis muscle is frequently targeted for botulinum neurotoxin injective treatment for spasticity. However, there are no injective guidelines for delivering injection to the muscle.
Materials And Methods:
A method known as the modified Sihler's method was used to stain the adductor pollicis muscle in 16 specimens to reveal intramuscular neural distribution of the muscle.
Results:
The most intramuscular neural distribution was located on 1/5 to 3/5 of the muscle regarding midline of 3rd metacarpal bone (0) to the base of the 1st proximal phalanx (5/5). The nerve entry point was mostly located on 0 to 1/5 of the muscle.
Conclusion:
The result suggests that botulinum neurotoxin should be delivered at the middle of second metacarpal bone via deep injection.
More Related Videos
Related Concept Videos
Directly Acting Muscle Relaxants: Dantrolene and Botulinum Toxin
The binding of dantrolene to the RYR1...
Classification of Skeletal Muscle Relaxants
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...
Skeletal Muscle Relaxants: Therapeutic Uses
Peripherally and Centrally Acting Muscle Relaxants: A Comparison
Centrally acting muscle relaxants can be further divided into spasmolytic and antispasmodic drugs. Spasmolytic...
Spasmolytic Agents: Chemical Classification
A major class of centrally acting spasmolytics is the α2-agonist, such as tizanidine. These drugs bind to α2-adrenoceptors, inhibiting the release of the excitatory neurotransmitter glutamate. They also...
Myasthenia Gravis: Overview and Treatment
These antibodies interfere with the function of the nicotinic receptors in three ways: by binding to the receptor and disrupting acetylcholine binding; by causing cross-linking of receptors which...

