Huge thoracolumbar extradural arachnoid cyst excised by recapping T-saw laminoplasty

Background contextSpinal extradural arachnoid cysts are rare expanding lesions in the spinal canal. Total removal of the cyst and repair of the dural defect is the primary treatment for symptomatic spinal extradural arachnoid cysts.PurposeTo report the usefulness of recapping T-saw laminoplasty in treating huge extradural arachnoid cyst.Study designCase report.MethodsWe report the case of a 43-year-old man who presented with a 2-year history of progressive muscle weakness and numbness of the lower extremities. Magnetic resonance imaging (MRI) showed a huge extradural arachnoid cyst at the T12–L3 level extending into bilateral neural foramina and severe posterior compression of the spinal cord and cauda equina.ResultsThe patient underwent total resection of the cyst and closure of the communication. En bloc recapping T-saw laminoplasty of T12–L2 including the T12–L1 and L1–L2 facet joints was performed to obtain extensive exposure and preserve posterior stability. Postoperatively, the patient achieved complete recovery of neurologic functions. Follow-up MRI demonstrated no recurrence of the cyst. Bone union after laminoplasty was obtained within 6 months.ConclusionTotal resection of the cyst and closure of the communication is curative for this rare lesion. Recapping T-saw laminoplasty provides extensive exposure for removal of a large cyst while allowing complete preservation of the posterior spinal elements.