Botulinum toxin type A for amyotrophic lateral sclerosis lower limb spasm: two case reports. - Duan, Qiang; Li, Chao; Wei, Chunxia; Wang, Qian; Wang, Bo; Sun, Liangwen; He, Yongjing; Qin, Junxia; Huang, Xiaoqun (BMC Neurology, 2025)