Purpose <p>Intradural migration of a lumbar disc prosthesis is an infrequent and previously unreported complication. We aimed to describe the clinical presentation, surgical management, and outcome of this unique case and to review relevant literature.</p> Methods <p>A 70-year-old man presented with progressive low back pain radiating to the right leg and foot drop, ten years after undergoing L3–4 total disc replacement. Magnetic resonance imaging and computed tomography demonstrated intradural migration of the prosthesis. The patient underwent L3–4 total laminectomy, durotomy with intradural prosthesis removal, and L3–L5 posterior stabilization.</p> Results <p>Radicular pain resolved immediately after surgery. Postoperative rehabilitation was initiated early, and the 3-month follow-up achieved complete recovery of foot dorsiflexion. Postoperative imaging confirmed the appropriate positioning of the hardware and the complete removal of the migrated prosthesis.</p> Conclusion <p>It is essential to note that these complications can occur even years after disc arthroplasty. Radiologic follow-up is recommended at 3 and 6 months, then annually during the first 5 years, and in selected patients at longer intervals thereafter. This case represents the first documented instance of intradural migration of a lumbar disc prosthesis. It highlights the technical nuances of intradural removal and demonstrates that complete neurological recovery is possible with prompt surgical intervention. </p>