Occurrence rates of the conjoint nerve roots were 55.4%,according to the shape of conjoint nerve roots,it could be divided into 5 types,according to the location of conjoint nerve roots,it was divided into 3 types.

• 后根间神经纤维联系出现率为55.；4%25；根据形状；可分为5型；根据位置；可分为3类。