Assessment of two measurement techniques of cervical spine and C1-C2 rotation in the outcome research of axis fractures: a morphometrical analysis using dynamic computed tomography scanning.
METHODS
In vivo study on cervical spine motion.


OBJECTIVE
To estimate the accuracy of clinical measurements, using a handheld goniometer for the assessment of total cervical neck rotation in outcome research of patients with C2 fractures and particularly odontoid fractures. Investigation on whether functional computed tomography (CT)-scanning is decisive in the investigation of functional outcome after C2 fractures.


BACKGROUND
Pertinent literature exists concerning indications, techniques, complications of treatment, and risk factors for nonunion in C2 fractures; however, there are scarce data regarding the functional outcome in C2 fractures. Only a few studies assess functional outcome in terms of clinical outcome vehicles and clinical investigation of axial neck rotation, using a handheld goniometer. Measurements of axial neck rotation using a handheld goniometer are assumed not sufficient to compare the results of treatment strategies for C2-fractures or elucidate the ability for posttreatment rotation of C1-C2.


METHODS
The authors selected a homogenous group of 35 patients treated for C2 fractures using nonsurgical and surgical techniques. 69% of patients had odontoid fractures. Mean age of patients was 52 years. Patients were subjected to clinical assessment of axial cervical range of motion for rotation, using a handheld goniometer. Patients were also subjected to functional CT-scanning and measurements of total neck and atlantoaxial rotation were performed according to an established protocol.


RESULTS
With clinical measurements mean range of motion for left and right axial neck rotation was both 56 degrees. According to the functional CT scans, the mean left-sided and right-sided axial neck rotation was 48.6 degrees and 52.0 degrees. The mean for left- and right-sided atlantoaxial rotation was 20.2 degrees and 20.6 degrees. Total axial atlantoaxial rotation on CT scans was 40.3 degrees and total axial neck rotation was 103.3 degrees. In comparison to age and gender matched normal individuals total cervical neck rotation was reduced to a mean of 69.5%. The differences between total axial neck rotation assessed using a handheld goniometer and with functional CT-scanning were strongly significant (P < 0.0001). In addition, there was no statistically significant correlation between the clinically assessed total neck rotation to either the left or the right side and the ipsilateral percentage atlantoaxial rotation of total head neck rotation.


CONCLUSIONS
The current study demonstrated that for the comparison of functional outcome after different therapies of C2 fractures clinical measurements do not serve for reliable data on total neck rotation and particularly atlantoaxial rotation and the percentage of C1-C2 rotation of total neck rotation. The use of dynamic CT-scans in the analysis of functional outcome after C2 fractures is strongly recommended.
Koller
Heiko
H
Department for Traumatology and Sports Injuries, Paracelsus Medical University Salzburg, Salzburg, Austria. heiko.koller@t-online.de
Resch
Herbert
H
Acosta
Frank
F
Zenner
Juliane
J
Schwaiger
Robert
R
Tauber
Mark
M
Forstner
Rosemarie
R
Lederer
Stefan
S
Auffarth
Alexander
A
Hitzl
Wolfgang
W
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001368:Axis, Cervical Vertebra / Q000000981:diagnostic imaging* / Q000502:physiology; D001270:Cervical Atlas / Q000000981:diagnostic imaging / Q000502:physiology; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000502:physiology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology; D012107:Research Design / Q000592:standards*; D012399:Rotation; D016103:Spinal Fractures / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards*; D016896:Treatment Outcome; D055815:Young Adult