通常将肉毒杆菌神经毒素A(BoNT-A)注射到腓肠肌内侧(MG)和小腿管型,以治疗痉挛型脑瘫(CP)儿童的踝部马蹄。然而,对肌肉或肌腱结构的分解治疗效果,伸展反射,和关节是未知的。在这项研究中,分别对MG进行BoNT-A注射和小腿铸造,以深入了解关节隔离治疗的工作机制。肌肉,和肌腱水平。31例痉挛型CP(GMFCSI-III,年龄7.4±2.6岁)接受了两周的小腿管型或MGBoNT-A注射。在缓慢和快速被动脚踝旋转的全范围运动中,测量关节阻力和MG拉伸反射。使用3D徒手超声评估静息和最大背屈踝角时的MG肌肉和肌腱长度。使用非参数统计学比较治疗效果。对关节和肌肉或肌腱水平的影响之间的关联使用Spearman相关系数(p<0.05)进行。增加接头阻力,在缓慢的脚踝旋转过程中测量,两种治疗后均未明显减少。在快速旋转期间评估的额外关节阻力仅在BoNT-A组中降低(-37.6%,p=0.013,效应大小=0.47),伴随着MG拉伸反射的减少(-70.7%,p=0.003,效应大小=0.56)。BoNT-A增加了在休息脚踝角度测量的肌肉长度(6.9%,p=0.013,效应大小=0.53)。铸造后关节角度向更大的背屈移动(32.4%,p=0.004,效应大小=0.56),伴随着肌腱长度的增加(5.7%,p=0.039,效应大小=0.57;r=0.40)。未发现肌肉或肌腱长度的变化与拉伸反射的变化之间存在关联。我们得出的结论是,肌内注射BoNT-A可减少MG的拉伸反射,并伴有静息肌肉腹部长度的增加。而铸造导致背屈增加,而肌肉长度没有任何变化。这支持需要进一步研究联合治疗的效果和更有效地延长肌肉的治疗的发展。
Botulinum NeuroToxin-A (BoNT-A) injections to the medial gastrocnemius (MG) and lower-leg casts are commonly combined to treat ankle equinus in children with spastic cerebral palsy (CP). However, the decomposed treatment effects on muscle or tendon structure, stretch reflexes, and joint are unknown. In this study, BoNT-A injections to the MG and casting of the lower legs were applied separately to gain insight into the working mechanisms of the isolated treatments on joint, muscle, and tendon levels. Thirty-one children with spastic CP (GMFCS I-III, age 7.4 ± 2.6 years) received either two weeks of lower-leg casts or MG BoNT-A injections. During full range of motion slow and fast passive ankle rotations, joint resistance and MG stretch reflexes were measured. MG muscle and tendon lengths were assessed at resting and at maximum dorsiflexion ankle angles using 3D-freehand ultrasound. Treatment effects were compared using non-parametric statistics. Associations between the effects on joint and muscle or tendon levels were performed using Spearman correlation coefficients (p < 0.05). Increased joint resistance, measured during slow ankle rotations, was not significantly reduced after either treatment. Additional joint resistance assessed during fast rotations only reduced in the BoNT-A group (-37.6%, p = 0.013, effect size = 0.47), accompanied by a reduction in MG stretch reflexes (-70.7%, p = 0.003, effect size = 0.56). BoNT-A increased the muscle length measured at the resting ankle angle (6.9%, p = 0.013, effect size = 0.53). Joint angles shifted toward greater dorsiflexion after casting (32.4%, p = 0.004, effect size = 0.56), accompanied by increases in tendon length (5.7%, p = 0.039, effect size = 0.57; r = 0.40). No associations between the changes in muscle or tendon lengths and the changes in the stretch reflexes were found. We conclude that intramuscular BoNT-A injections reduced stretch reflexes in the MG accompanied by an increase in resting muscle belly length, whereas casting resulted in increased dorsiflexion without any changes to the muscle length. This supports the need for further investigation on the effect of the combined treatments and the development of treatments that more effectively lengthen the muscle.