Guidelines for botulinum neurotoxin injections in piriformis syndrome

Abstract

Background The piriformis muscle is normally involved in piriformis syndrome and can be treated with botulinum neurotoxin using several different injection methods. However, definitive injection guidelines for the muscle have not been reported previously. Aims This study aimed to determine the ideal area for injections based on the intramuscular nerve distribution as obtained using a modified Sihler's staining technique. Materials and Methods A modified Sihler's method was applied to the piriformis muscle in 15 specimens. The intramuscular arborization areas were identified based on two anatomical landmarks: (a) the lateral border of the sacrum bone and (b) the greater trochanter. Results The nerve entry point for both piriformis muscles was found in the area between the lateral border of the sacrum and one‐fifth of the distance toward the greater trochanter. The intramuscular nerve distribution for the piriformis muscle had the largest arborization patterns between one‐fifth and two‐fifths of the distance from the sacrum to the greater trochanter. The piriformis muscle was tendinous from two‐fifths of the distance to the greater trochanter. Discussion This study has yielded suggested optimal injection locations for the piriformis muscle relative to external anatomical landmarks. Conclusion Clinicians can use these guidelines to ensure the effectiveness of not only botulinum neurotoxin injections but also other agents such as steroids, anesthetics, and normal saline. These guidelines will also help to avoid adverse outcomes of injection treatments.

Novel Anatomical Guidelines on Botulinum Neurotoxin Injection for Wrinkles in the Nose Region

“…Although sensitivity to BoNT differs among individuals, there is no effective treatment for ptosis, which persists for several months [ 31 , 32 ]. Accurate BoNT injection points from an anatomical point of view have been suggested in various studies concerning BoNT injection in specific muscles [ 16 , 17 , 18 , 19 , 20 , 21 , 33 , 34 , 35 , 36 , 37 ]. According to the meta-analysis conducted by Camargo et al, most studies had duration of treatment of 5 months [ 38 ].…”

“…Numerous studies on BoNT injection points in muscles have previously been published on external anatomical standards ( Figure 2 ) [ 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 ]. We searched for articles using the following keywords: “botulinum neurotoxin in nose region” and “side effect of botulinum neurotoxin injection in nose wrinkle” on Pubmed and Scopus.…”

Intramuscular Neural Arborization of the Latissimus Dorsi Muscle: Application of Botulinum Neurotoxin Injection in Flap Reconstruction

“…Thus, to lessen the undesirable effects and enhance efficiency, LD muscle BoNT injection should be targeted into the neural arborized zones. Studies have focused primarily on identifying the intramuscular arborized zones and guidance injectable points for BoNT treatments [35][36][37][38][39][40][41][42][43][44][45].…”

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

“…Studies that explain BoNT injection locations by navigating intramuscular neural distribution with naked eye dissection have limits, such as perceiving minuscule nerves and the likelihood of neural damage [17,21,25,[41][42][43][44][45][46][47][48][49].…”