The purpose of this study is to investigate the difference of the accuracy and safety between traditional spine surgery and computer assisted navigation system spine surgery.

The object of study is the patients who are going to undergo pedicle screw fixation operation. there are two clinical trial centers.one is beijing jishuitan hospital,the other is beijing shuili hospital.the study protocol will be reviewed by the Ethics Committee of Beijing Jishuitan Hospital. after the patients sign the informed consent,they will be divided into two groups randomly.the patients' basic information and medical informations including the accuracy and safety will be collected.the data above all will be compared.

Inclusion Criteria:

• Patients who need to undergo pedicle screw fixation surgery
• Sign informed consent
• Capacity person

Exclusion Criteria:

• refused to sign the informed consent
• the age is not between 18 and 75 years old