Chapter 38 Movement disorders: spasticity

Abstract

Publisher Summary Spasticity is not a neurological disease, but a motor disorder or syndrome characterized by a velocity-dependent increase of muscle tone sometimes combined with the clasp knife phenomenon and exaggerated monosynaptic and oligosynaptic stretch reflexes and polysynaptic tonic reflexes. Clinically, the increase of stretch reflexes is often combined with reflex irradiation—that is, the application of a phasic stretch by a reflex hammer and the mechanical effects of the primarily contracting muscle lead to excitation of muscle spindles and reflexes in distant muscles. Especially in triceps surae and quadriceps, muscle clonus may arise after sudden stretch of these muscles. Most clinicians also regard Babinski's reflex as a representative symptom of spasticity. In the discussion of clinical aspects and treatment of spasticity, spasms, and upper motor neuron syndromes (UMSs), three major problems arise. The first problem facing a clinician is to diagnose and correctly interpret the symptoms observed. The second clinical relevant problem is to delineate that disease in an individual patient causing spasticity or an UMS is present. The third problem is to decide, which causal therapy if available is to be applied and how symptomatic therapy of spasticity and the other features of the UMS can be used in the individual patient. Except some forms of genetically determined spastic paraplegias, spasticity usually does not occur separately; in nearly all diseases, spasticity is embedded in an UMS.