该怎么划层次

The most common risks to surgery are pain, complications from bleeding, infection, nerve injury, dural tears, pseudoarthrosis, and adjacent segment disease.

别的老师翻译的：手术最常见的风险是疼痛、出血、感染、神经损伤、硬膜撕裂、假关节病及邻近节段疾病。

这句后我觉得后面分3个层次，1.pain、2.complications（bleeding, infection, nerve injury, dural tears, pseudoarthrosis）、3.pseudoarthrosis, and adjacent segment disease

如果分析对的话，就是这样，修改：手术最常见的风险是疼痛、合并症（出血、感染、神经损伤、硬膜撕裂）、以及假关节病及邻近节段疾病。