Anatomical locations of the motor endplates of sartorius muscle for botulinum toxin injections in treatment of muscle spasticity.

[PURPOSE] This study aimed to detect the idyllic locations for botulinum neurotoxin injection by analyzing the intramuscular neural distributions of the sartorius muscles.

[METHODS] An altered Sihler's staining was conducted on sartorius muscles (15 specimens). The nerve entry points and intramuscular arborization areas were measured as a percentage of the total distance from the most prominent point of the anterior superior iliac spine (0%) to the medial femoral epicondyle (100%).

[RESULTS] Intramuscular neural distribution were densely detected at 20-40% and 60-80% for the sartorius muscles. The result suggests that the treatment of sartorius muscle spasticity requires botulinum neurotoxin injections in particular locations.

[CONCLUSIONS] These locations, corresponding to the locations of maximum arborization, are suggested as the most suggestive points for botulinum neurotoxin injection.