Research On The Value Of The Diagnosis Of Atlantoaxial Rotatory Fixation With MSCT Imaging In Rotary Functional Position

Objective:To research on the value of the proper diagnosis of atlanto axial rotatory subluxation with MSCT imaging in rotary functional position through analyzing and comparing the various imaging features of normal people and patients with atlantoaxial rotatory fixation in neutral position and rotary functional position by using MSCT.Methods:51 volunteers were randomly selected and divided into two groups.One group was younger than 50 and the others formed another group.They were scanned by MSCT in neutral position and rotary functional position in order to compare the variations of ADI,|VBLADS|and RAAD in different rotation state between different ages.35 patients who were under suspicion of being with atlantoaxial rotatory subluxation were examined with MSCT in neutral position and rotary functional position.An analysis was made on the variations of ADI,|VBLADS|,RAAD and the displacement of lateral atlantoaxial joint surface in different rotation state between normal people and patients with atlantoaxial rotatory subluxation.Results:Independent sample t test(P<0.05)was conducted on ADI,|VBLADS| and RAAD of the two groups with different ages in neutral position and rotary functional position.The result showed that the group with younger age had a larger RAAD and more variability on ADI and |VBLADS| than another group whose age were older than 50.Pearson correlation analysis was carried on |VBLADS| and RAAD of normal volunteers and the result indicated that the size of|VBLADS| had no correlation with the rotation function between atlas and axis.The atlanto-axial joint of 35 patients in neutral position and rotary functional position appeared to be relatively fixed and all the patients had the displacement of lateral atlantoaxial joint surface with diferent degrees.The ADI,|VBLADS| and RAAD of normal volunteers and patients in neutral position and rotary functional position were tested with independent sample t test(p<0.05),respectively.The results showed that there were statistically differences between two groups in rotary functional position.Conclusions:The dynamic changes of atlanto-axial joint can be reflected objectively with MSCT examination in neutral position and rotary functional position and it has an important clinical application value on the diagnosis of atlantoaxial rotatory subluxation.