Cervical spinal motion before and after surgery in patients with Chiari malformation Type I associated with syringomyelia

Abstract

Object There have been few reports about the cervical spinal motion in patients with Chiari malformation Type I (CM-I) associated with syringomyelia. To investigate this phenomenon, the relationship between the preoperative cervical range of motion (ROM) and the stage of cerebellar tonsillar descent as well as the cervical ROM before and after foramen magnum decompression (FMD) were evaluated. Methods Thirty patients who had CM-I associated with syringomyelia and who underwent FMD participated in the study. The ROM and lordosis angle of the cervical spine were measured on x-ray films. In addition, the relationship between preoperative degree of cerebellar tonsillar descent and the ROM between the levels of the occiput (Oc) and C2 was investigated. Results The mean flexion–extension ROM at Oc–C2 was 15.5° before and 14.1° after surgery, and the mean flexion–extension ROM of C2–7 was 55.1° before and 52.8° after surgery. The mean pre- and postoperative lordosis angles at C2–7 were 16.8 and 19.1°, respectively. There was no significant difference between the values measured before and after surgery. There was no correlation between the degree of cerebellar tonsillar descent and the ROM at Oc–C2. Conclusions Foramen magnum decompression is an excellent surgical technique that has no effect on the postoperative cervical ROM and cervical alignment.