Cervical Alignment of Patients with Basilar Invagination: A Radiological Study

Abstract

Objective: To investigate the cervical alignment and the relative range of motion (ROM) in patients with basilar invagination (BI).Methods: A total of 40 BI cases (38.1 years old AE 17.9 years old, 19 male and 21 female) and 80 asymptomatic individuals (33.8 years old AE 10.8 years old, 40 male and 40 female) were included. The Skull-C 2 /Skull-BV, Skull-C 7 , C 2 -C 7 /BV-C 7 wall angles, C 0 -C 2 /C 0 -BV, C 0 -C 7 , C 1 -C 7 , and C 2 -C 7 /BV-C 7 angles were measured in dynamic X-ray images (including neutral, extension, and flexion positions). Correlation between the upper and lower cervical curvatures were analyzed. The total, extension, and flexion ROMs of these angles were calculated, respectively. Results:The BI patients had a smaller C 0 -C 2 /C 0 -BV angle (18.2 AE 16.4 vs 30.9 AE 9.3 ), but larger C 2 -C 7 /BV-C 7 (32.2 AE 16.1 vs 19.4 AE 10.6 ) and C 2 -C 7 /BV-C 7 wall angles (37.8 AE 17.2 vs 23.6 AE 10.2 ) than the control group in neutral position. The upper and lower curvatures correlated negatively in neutral (r = À0.371), extension (r = À0.429), and flexion (r = À0.648) positions among BI patients, as well as in extension position (r = À0.317) among control group. The BI patients presented smaller total ROMs in Skull-C 2 /Skull-BV (12.3 AE 16.6 vs 19.7 AE 10.9 ), C 0 -C 2 /C 0 -BV (8.1 AE 11.1 vs 17.6 AE 10.5 ), and C 0 -C 7 angles (57.8 AE 14.2 vs 78.3 AE 17.9 ), but a larger total ROM in C 2 -C 7 /BV-C 7 wall angle (52.8 AE 13.9 vs 27.0 AE 16.1 ) than the control group. The BI patients also presented smaller extension ROMs in Skull-C 2 /Skull-BV (6.9 AE 9.4 vs 12.5 AE 9.3 ), Skull-C 7 (24.5 AE 10.9 vs 30.7 AE 12.5 ), and C 0 -C 2 /C 0 -BV angles (4.4 AE 7.8 vs 9.9 AE 8.6 ) than the control group. Moreover, the BI patients showed smaller absolute values of flexion ROMs in Skull-C 2 /Skull-BV (À5.2 AE 9.4 vs À7.3 AE 8.0 ), C 0 -C 2 /C 0 -BV (À3.2 AE 8.8 vs À7.7 AE 8.7 ), and C 0 -C 7 angles (À33.2 AE 13.0 vs À52.8 AE 19.2 ), but a larger absolute value of flexion ROM in C 2 -C 7 /BV-C 7 wall angle (À33.9 AE 14.8 vs À8.2 AE 15.1 ). Conclusion:The cervical spine was stiffer in BI patients than the asymptomatic individuals, especially in the upper cervical curvature. The negative correlation between upper and lower cervical curvatures was more obvious in BI patients.

The Morphological Evaluation of the Cervical Muscle in Patients With Basilar Invagination: A Magnetic Resonance Imaging-Based Study

“…Due to the prolapse of odontoid into the foramen magnum, the medulla oblongata and spinal cord are compressed which result in neural symptoms in BI patients. The BI patient was found to present a stiffer neck [ 6 ]. We deduced that the BI patient needed to maintain their cervical spine in a certain posture to reduce discomfort.…”

“…In the present study, the results indicated that functional muscles were less in BI patients and decreased with age with more obvious trends than control group. Furthermore, our previous study also revealed that BI patients presented the loss of cervical curvature [ 6 ]. Therefore, early exercise on both cervical extensor and flexor muscles is necessary to alleviate fatty infiltration and strengthen muscle function.…”

“…Basilar invagination (BI) is known as deformity of the craniocervical junction (CVJ) region with or without clinical neural symptoms [ 1 - 3 ]. Our team conducted a series of research, focused on the changes in skeletal anatomy in BI patients and reported the characteristics of CVJ structures [ 4 - 6 ]. We previously found that the BI patients presented stiffer cervical alignment than the asymptomatic population [ 6 ].…”

“…Our team conducted a series of research, focused on the changes in skeletal anatomy in BI patients and reported the characteristics of CVJ structures [ 4 - 6 ]. We previously found that the BI patients presented stiffer cervical alignment than the asymptomatic population [ 6 ]. It was deduced that the cervical muscles might contribute to the consequences.…”