Cervical jerks as a sign of cervical pain or myelopathy in dogs.

OBJECTIVE: To describe and classify cervical muscle jerks associated with cervical pain or myelopathy and evaluate their clinical and diagnostic relevance. ANIMALS: 20 dogs with a history of unilateral or bilateral cervical jerks associated with cervical pain or myelopathy. PROCEDURES: A retrospective study. Detailed history, complete clinical and neurological examinations, CT studies, and outcome were available for each dog. All dogs received a treatment adapted to each diagnosis. The presence or absence of jerks was evaluated at short- and long-term recheck examinations. An immediate postoperative CT scan was obtained for all cases that were treated surgically. RESULTS: 20 dogs were selected for the study, 13 of which were French Bulldogs. Jerks all presented as focal repetitive rhythmic contractions on the lateral aspect of the neck (on one or both sides). All dogs had a diagnosis of cervical intervertebral disk extrusion (IVDE), half of them at the C2-C3 level. No dogs presented with extrusion caudal to the C4-C5 intervertebral disk space. The prevalence of myoclonia among all dogs diagnosed with IVDE was 3.77% (20/530) in our hospital. CLINICAL RELEVANCE: Cervical jerk associated with cervical pain or myelopathy may represent myoclonus and was exclusively secondary to cranial cervical IVDE in this study. Full recovery was observed following medical or surgical treatment of IVDE. The exact origin and classification of this involuntary movement has yet to be established.