A 4-year-old, 750-g, female emperor tamarin (Saguinus imperator) was presented for a routine health exam under anesthesia. The following day, the tamarin appeared weak in the rear limbs. Three days after the exam, the tamarin was re-examined due to signs of urinary retention and tail and bilateral rear limb weakness. The urine retention and rear limb weakness improved over the next 2 weeks with antibiotic and anti-inflammatory treatment, but the tail remained hypotonic. Six months later, the tamarin developed left leg weakness. There was no improvement in limb weakness during one week of antibiotic and steroid therapy. A magnetic resonance image revealed a space-occupying mass in the spinal canal at L3-4. During the next five days, the left leg weakness progressed and right leg weakness developed. A dorsal laminectomy was performed to remove a cavernous angioma and a blood clot. Over the following 5 months, the tamarin regained full use of the right rear limb but continued to have residual left rear limb dysfunction. The tail was partially amputated due to repetitive trauma secondary to lost function. One year later, the tamarin has adapted well to the residual left rear limb dysfunction and partial tail amputation.