Intrathecal enzyme replacement therapy to treat spinal cord compression in mucopolysaccharidosis: Overview and rationale.

Spinal cord compression has been described in mucopolysaccharidosis I, II, IV, VI, and VII. The spinal cord compression in the mucopolysaccharidoses is believed to originate from narrowing of the vertebral canal due to bony abnormalities, and thickening of the meninges and spinal ligaments due to glycosaminoglycan infiltration [12]. The current standard of care involves surgical decompression. However, the surgery is extensive, MPS patients are high-risk surgical and anesthesia candidates, and the problem may recur after surgery. Neurosurgical treatment of spinal cord compression involves a multi-level decompressive laminectomy and opening of the thickened dura [12]. Many patients also require a suboccipital craniectomy. Some patients require instrumentation and fusion because they have ligamentous or spinal instability. Overall, the surgical repair can be more extensive than that required for spondylotic degeneration and myelopathy in normal elderly individuals.