由于发生意外事故,压碎或切断脊髓时,结果常发生不可恢复的终生截瘫,从腰部以下麻痹。目前美国有150,000例截瘫病人。其原因很简单,因为脊髓的主要神经细胞一旦断裂后,就不能再生长。但最近5年来,美国国立卫生研究院神经病研究所的研究经费每年从100万增加到760万。世界文献中有关这方面的科学论文从1970年的很少几篇到去年增至500篇。美国国立神经病、传染病及中风研究所所长托尔(Donald Tower)说,自五十年代开始, As a result of accidents, crushing or cutting off the spinal cord often results in unrecoverable lifetime paraplegia that paralyzes below the waist. There are currently 150,000 paraplegic patients in the United States. The reason is simple, because once the main nerve cells in the spinal cord break, they can not grow anymore. However, in the last five years, the research funding of the Institute of Neurology at the National Institutes of Health has increased from 1 million to 7.6 million annually. The number of scientific papers in this field increased from 500 in 1970 to 500 in the previous year. Donald Tower, director of the National Institute of Neurological, Communicable Diseases and Stroke, said that since the 1950s,