Case Report: Microchip Implantation Within the Cervical Spine, a Neurologic Evaluation, and Surgical Correction

A 5 mo old male Japanese chin was examined 1 mo following the sudden onset of pelvic limb weakness and ataxia immediately after microchip placement. Neurological examination revealed an ambulatory paraparesis, which was worse on the right side, with additional weakness noted in the right thoracic limb. Lesion localization was C6-T2 spinal cord segments, worse on the right. Radiographic imaging of the cervical spine revealed a microchip at the location of the C7-T1 intervertebral space. Computed tomography revealed a microchip within the spinal canal causing spinal cord compression at the level of the C7-T1 intervertebral disc space. Surgical removal of the microchip was performed, and the patient recovered well. A 6 wk follow-up neurologic examination showed persistent mild ataxia in the pelvic limbs. This case supports previously reported cases of permanent spinal cord damage caused by microchip placement. Surgical removal of the microchip resulted in the improvement of neurologic signs. Although extraction of the microchip did not resolve all neurologic deficits, surgery prevented further migration and possible damage to the spinal cord.