Objective:To investigate the influence of cervical dynamic MRI on the stability of CPA Angle, and whether it has more clinical diagnostic value compared with CXA and CDA Angle.1.2. Methods: 15 healthy clinical subjects underwent MRI examination in neutral position, hyperextension position and hyperflexion position at the same time. The value of three angles (CPA, CXA and CDA) were measured, and the t test was used to compare the changes of different positions. Results:The paired T-test showed that CPA had no significant difference in Angle measurement from neutral cervical vertebra to hyperextension cervical vertebra, and was significantly stable to CXA and CDA. Secondly, CPA changed the least from neutral position to overflexion position, followed by CXA, and CDA changed the most. Conclusion:CPA is the least sensitive and most stable to cervical curvature. Especially, the difference between neutral position and overextension position is the least, and the stability is obviously better than CXA and CDA.