Computer Modelling of the Cervical Spine Movements in Cervical Dystonia

Cervical dystonia (CD) is a syndrome characterized by sustained and/or phasic involuntary neck muscle activity causing abnormal head postures and movements. It is the most frequent form of adult focal dystonia. The distribution of dystonic muscles is unique for each patient, explaining the variety of patterns encountered.

The therapeutic management of CD is essentially local and symptomatic: Botulinum Neurotoxin injections and/or specific retraining therapy programmes. Therefore, analyzing the characteristics of abnormal head movements and identifying the dystonic muscles are the key points of these treatments.

To a better understanding of the posture and movement disorders of head and neck, we wish to establish a three-dimensional (3-D) computer model of cervical spine movements of ten healthy subjects built from images obtained with the "Cone Beam " system. Then we will compare the cervical posture and movements for each of ten CD patients matched in age and genre to the computer model. Comparison with patients' images in the axial plane reconstructed by computer with the 3-D computer model will lead to the description of various patterns of CD. Analysis of the musculoskeletal disturbances in CD should be a help to improve the localization of Botulinum Neurotoxin injection sites as well as retraining programmes.