PMC5424375_01
a Sagittal T2-weighted MR image revealing caudal occipital malformation, kinking of the caudal medulla, foramen magnum herniation (arrow), and a T2-hyperintense intramedullary signal within the spinal cord extending from C1 to C3. Transverse FLAIR image at the level of C2 (broken arrow, inset), demonstrating the hypointense syrinomyelic cavity in the dorsal spinal cord. b Lordotic posture resulting from axial muscular rigidity. Superimposed muscle spasms cause partial flexion of the limb joints, including the digits (arrow). c Resting EMG revealing continuous motor unit activity in the lumbar epaxial musculature
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PMC5424375_01_40734_2017_53_Fig1_HTML.jpg
Fig1
Chiari-like malformation (CM) and secondary syringomyelia (Fig. 1a). Cerebrospinal fluid (CSF) was collected from the cerebellomedullary cistern. The dog demonstrated rigidity of the axial and proximal appendicular muscles resulting in lordosis (Fig. 1b) that impaired ambulation. Superimposed upon the stiffness were spontaneous and tactile stimulus-induced generalized muscular spasms that had a stereotyped appearance, characterized by an initial flexion and abduction of the limbs (Fig. 1b). An EMG was also performed, and continuous motor unit activity was noted in the cervicothoracic and lumbar axial muscles at rest (Fig. 1c).