Technical nuances for microsurgical reduction of lateral spinal cord herniation: illustrative case.

BACKGROUND

Spinal cord herniation (SCH) is exceedingly rare, with most cases occurring in the ventral thoracic spine. To date, there is only one reported case in the existing literature detailing pure lateral thoracic SCH. A 23-year-old male presented with progressive thoracic myelopathy and neurological deficits. Imaging revealed a large, left-sided dural diverticulum at T3-4 with an impressive SCH extending out the neural foramen.

OBSERVATIONS: The patient underwent T2-4 laminectomies, left T3-4 facetectomies, partial pediculectomies, and transverse process removal for intradural spinal cord detethering and reduction of the lateral herniation. An AlloDerm buttress was placed within the dural diverticulum laterally, and the contralateral dentate ligaments were sutured to the medial dura as secondary means of preventing reherniation and retethering. The patient remains functionally stable at 20 months postoperatively.

LESSONS: Lateral SCH must be recognized as a distinct pathological entity requiring individualized surgical planning. Strategies should focus on preventing reherniation and mitigating tethering forces rather than attempting conventional dural repair. Coexisting spinal deformity may meaningfully influence cord dynamics and should be incorporated into both pathophysiological understanding and operative decision-making. The complexity of managing such cases underscores the need for technical discussions within the neurosurgical community. https://thejns.org/doi/10.3171/CASE26188.