The pathogenic mechanisms of motor weakness following aneurysmal subarachnoid hemorrhage: a review

Motor weakness is one of the neurological complication that can occur after aneurysmal subarachnoid hemorrhage (SAH)incidence of motor weakness of 14~29% has been reported. Detailed information on the pathogenic mechanism of motor weakness is essential for brain rehabilitation because it enables estimation of the severity of injury, establishment of scientific rehabilitative strategies, and prediction of motor outcomes by clinicians. However, the exact pathogenic mechanisms of motor weakness following aneurysmal SAH have not been clearly elucidated. In this article, 14 previous studies on pathogenic mechanisms in patients with aneurysmal SAH were reviewed according to the location of the lesion (cerebral cortex, brainstem, spinal cord, and peripheral nerve). The following pathogenic mechanisms have been suggested: vasospasm, cerebral ischemia, hydrocephalus, compression of cerebral cortex, neural injury, spinal cord infarction, and radiculo-neuropathy. Considering the high incidence of aneurysmal SAH and motor weakness following aneurysmal SAH, we believe that the pathogenic mechanisms of motor weakness have been relatively understudied. More effort should be taken to investigate this important topic