Mapping the limb muscle motor points for targeted administration of botulinum toxin in the treatment of focal and segmental spasticity

Abstract

Spasticity treatment remains an urgent problem of modern neurorehabilitation. The targeted injection of botulinum neurotoxin (BoNT) into the muscle motor points (MPs) is gaining more and more popularity. But there are insufficient data on the position of MPs, while a MP search methodology has not been worked out yet. Most information about MPs has been obtained on cadaveric material using anatomical dissection or Sihler’s staining technique. Clinical data on the targeted injection of BoNT into the MPs are contradictory, which may be due to the inaccurate determination of their position.Objective: to verify upper and lower limb muscle MPs through electromyography (EMG).Patients and methods. Forty healthy volunteers were examined and underwent anthropometric assessment. Upper and lower limb muscle projections were completely scanned using EMG and ultrasound.Results and discussion. The anatomical localization of MPs in the upper and lower limb muscles involved in spasticity patterns was determined. The position of MPs was found to populationally identical, to have a slight deviation associated with the limb length, and to be unrelated to gender, age, and limb dominance. Original tables and maps for limb MP localization were created.Conclusion. The findings can enhance the efficiency of BoNT administration and improve the quality of rehabilitation measures, since the use of reliable information on the position of MPs will allow targeted BoNT injection in the immediate vicinity of the site of biological action. In clinical practice, this opens a window of opportunity for the early initiation of rehabilitation measures aimed at restoring movement.