Thoracic spinal cord compression caused by a giant T4–T5 enchondroma in Ollier disease

Background: Ollier disease is a rare nonhereditary skeletal dysplasia characterized by multiple enchondromas. Axial involvement, particularly of the thoracic spine, causing spinal cord compression, is exceedingly uncommon. Case Description: A 21-year-old female with Ollier disease presented with 3 months of progressive bilateral lower-extremity weakness, culminating in acute paraplegia, and a T6 sensory level, but with preserved sphincter function. The computed tomography and magnetic resonance imaging studies demonstrated a large dumbbell- shaped extradural mass at T4–T5 extending into the left paravertebral region resulting in extensive bony remodeling and severe spinal cord compression. A T2–T6 laminectomy allowed for complete resection of the intraspinal component of the mass and full decompression of the spinal cord. The patient improved immediately after surgery and recovered 4/5 strength in both legs by postoperative day 1. Conclusion: Thoracic spinal cord compression from enchondromas in Ollier disease is extremely rare. Posterior decompression is an effective urgent strategy that can achieve rapid neurological improvement, even in cases presenting with acute paraplegia.