Pathological changes and repair features of chronic spinal cord injury

Objective: To analyze the research progress of the pathology and treatment of chronic spinal cord injury, at present the quantity of patients with chronic spinal cord injury increases, and repair of chronic spinal cord injury is urgent day by day. Data sources: Using the key terms of "spinal cord injuries, chronic desease", the relevant articles about chronic spinal cord injury published from January 1985 to October 2005 in English were searched in Medline database by computer. Meanwhile, using the same key terms in Chinese, we searched the CNKI database from January 2000 to October 2005. Study selection: All articles were selected firstly, and articles related to the researches of therapy of chronic spinal cord injury were selected. The articles "published in authoritative magazine in recent 5 years were selected firstly if they were similar content. Data extraction: Of 400 retrieved articles, a total of 90 literatures were about the pathology and repair for chronic spinal cord injury. At last, 40 articles of pathology and repair for chronic spinal cord injury were collected. Data synthesis: As compared with the acute spinal cord injury, in chronic injury period the growth capacity of nerve fiber decrease, and the microenvironments surrounding the injury site did not support the regeneration of chronically injured axons. Many of treatments that had stimulated regeneration after acute injures were not able to produce lengthy regeneration. Conclusion: The pathological characteristics of the chronically injured spinal cord make it more challenging to repair. It is rare to realize the lengthy growth of chronically injured spinal cord towards opposite injured side.