Autonomic hyperreflexia following passive stretching to the hip joint.

Autonomic hyperreflexia may occur in patients with severe upper thoracic and cervical spinal cord lesions. This syndrome, consisting of episodic hypertension, bradycardia, diaphoresis, and headaches, is an autonomic reflex evoked by a variety of stimuli applied below the level of injury. This article describes three cases in which autonomic hyperreflexia was provoked by passive hip joint stretching.