Rushworth G
Int Rehabil Med. 1980;2(1):23-6. doi: 10.3109/09638288009163950.
In spite of the different uses of the term "spasticity", hyperactivity of skeletal muscle stretch reflexes is the one common factor and we therefore need to know how this is produced by lesions within the central nervous system and what are its consequences to the initiation and execution of voluntary movement, not only initially but also chronically. The alpha motoneurone is directly responsible for the initiation of skeletal muscle contraction and final integration of excitatory and inhibitory nervous input normally takes place on its surface. In spasticity there is not only loss of descending direct excitatory and inhibitory control of motoneurones, but also loss of the control of spinal interneurones which would normally regulate (principally by inhibition) segmental spinal reflexes, including the stretch reflexes, especially those concerned with antigravity muscles. Gamma motoneurones may also have a reduction inhibitory control with consequent increase of muscle spindle sensitivity to stretch, and this may be further exaggerated by changes in the physical properties of affected muscles. The peripheral disorders of function are more accessible to study and to pharmacological and physical treatment, but with the increasing knowledge of inhibitory mechanisms and their pharmacology there is hope that some degree of influence may be possible within the central nervous system, by therapy with drugs that mimic or prolong the action of inhibitory transmitters.
尽管“痉挛”一词有不同的用法，但骨骼肌牵张反射亢进是一个共同因素。因此，我们需要了解中枢神经系统内的病变是如何导致这种情况的，以及它对随意运动的发起和执行有何影响，不仅是在最初阶段，而且是长期的。α运动神经元直接负责引发骨骼肌收缩，兴奋性和抑制性神经输入的最终整合通常发生在其表面。在痉挛状态下，不仅运动神经元失去了下行的直接兴奋性和抑制性控制，而且脊髓中间神经元的控制也丧失了，而这些中间神经元通常（主要通过抑制）调节脊髓节段性反射，包括牵张反射，特别是那些与抗重力肌有关的反射。γ运动神经元的抑制性控制也可能减弱，从而导致肌梭对牵张的敏感性增加，而受影响肌肉物理特性的改变可能会进一步加剧这种情况。功能的外周紊乱更容易进行研究以及药物和物理治疗，但随着对抑制机制及其药理学知识的不断增加，人们希望通过使用模拟或延长抑制性递质作用的药物进行治疗，有可能在中枢神经系统内产生一定程度的影响。
