Dystonia (Muscular Rigidity Causing Spasms)

Dystonic means relating to abnormal muscular tension and, strictly speaking, the term encompasses both excessive or exaggerated tone and deficient or absent tone.

However, in common usage, the term describes an abnormal muscular rigidity causing painful and sustained muscle spasms of some part of the body, unusually fixed postures, or strange movement patterns.

Dystonic movements usually take the form of a twisting or turning motion of the neck, the trunk, or the proximal parts of the extremities. They are therefore powerful and deforming, grossly interfering with voluntary movement, and perverting posture.

  • Acute dystonia may occur as a transient complication of neuroleptic medication.
  • Torsion dystonia—torsion means twisting—is a term sometimes used to describe involuntary movements of a slow, powerful character, which produce tension and torsion spasms of the limbs and spine. The consequential abnormalities of gait may be quite bizarre.
  • Wry neck or torticollis (Latin for “crooked neck”) is a common example of torsion dystonia. It describes a twisting of the neck which causes the head to be rotated and tilted into an abnormal position, in which it remains.
  1. J.D. and J.A. Spillane, An Atlas of Clinical Neurology (Oxford Medical Publications, 3rd ed., 1982), p.263.