Fiducial-marked laminectomy window for intrathecal medication administration after spinal fusion: illustrative case

Spinal muscular atrophy (SMA) is an inherited disease that leads to weakness, loss of ambulation, and progressive scoliosis in many patients, frequently requiring early spinal fusion. Nusinersen is a disease-modifying agent that improves symptoms and slows the progression of SMA but requires serial lumbar punctures for intrathecal drug delivery. Spinal fusion for scoliosis has historically been a contraindication for nusinersen therapy, as the fused spinal laminae block access to the thecal sac.

Here, the authors report a case wherein a patient with SMA and prior scoliosis surgery underwent a one-level lumbar laminectomy with the placement of four titanium microscrews at the corners of the bone window thatfunction as fiducial targets for radiography-guided lumbar punctures. This procedure allowed the patient to receive nusinersen injections easily and successfully on an ongoing basis.

Nusinersen is an important novel treatment for children with SMA. Thus, it is imperative to discover new ways to administer intrathecal injections to increase the number of patients able to undergo this therapy. The described one-level laminectomy with microscrew placement for serial lumbar punctures can increase the number of patients able to receive nusinersen and other intrathecal therapies. https://thejns.org/doi/10.3171/CASE24411.