Methods: The following case report describes the synergistic effect of Incobotulinum toxin type A and physiotherapy in a 7-year-old patient with MYH3 mutation-related Klippel–Feil syndrome (KFS) complicated by bilateral paraplegia to improve the spasticity condition of the lower limbs. This evidence concerns the gene MYH3 and Klippel-Feil syndrome 1, autosomal dominant.