Intradural lumbar disc herniation: illustrative case

Intradural Disk Herniation at the Conus Medullaris: A Case Report With Emphasis on Patient Positioning and Neuromonitoring

CASE

A 73-year old man who underwent previous L2-S1 decompression presenting with new right radicular leg pain. Imaging suggests a large central disk herniation at L1-2 with possible intrathecal extension requiring surgical decompression. When positioned prone on a Jackson frame, neuromonitoring motor signals became diminished, and thus, the case was aborted. On returning to the operating room 2 days later, careful positioning in a more neutral/flexed position facilitated normal neuromonitoring signals, allowing for an uneventful intradural approach and discectomy.

CONCLUSION

With conus-level intrathecal disk herniation, consider using prepositional neuromonitoring and avoid hyperextension with positioning to ensure neurological safety.

MRI of difficult discs

Diagnosis of disc herniation is a daily task for radiologists. Although diagnosis is usually straightforward, it may become more difficult due to disc location. Disc herniations in the neural foramen or lateral to it can be overlooked if sagittal images are not obtained far enough laterally, and are often best seen on coronal images. Intradural disc herniations should be recognised preoperatively by their distinctive shape; recognition prepares the surgeon for the need to perform a durotomy and dural repair. Sequestered discs are often lentiform and inconspicuous on sagittal images. They can be missed if axial images are obtained only through the level of the intervertebral disc. Mimics of disc herniation must also be kept in mind when reviewing magnetic resonance imaging (MRI) studies: these include disc osteophyte complex, epidural haematoma, facet joint cyst, and tumours such as meningioma, nerve sheath tumours, and metastases.

Herniating Intradural Disc at Lumbar L4-L5 Level: A Case Report

Prolapse of intervertebral disc is a common pathology seen in the neurosurgery field but intradural lumbar disc herniation is a rare entity encountered only during the surgical treatment of prolapse. We present a 30-year-old male who reported lower back pain radiating to the right lower limb for the last 2.5 years. The pain started after a brief history of weight lifting. There were no associated motor or sensory deficits. The magnetic resonance imaging of the lumbosacral spine showed prolapse of intervertebral disc at the level of lumbar L4-L5. The patient underwent laminectomy and intradural discectomy of L4-L5. Patient had a smooth post-operative recovery with no neurological deficits. A thorough radiological examination can aid in the pre-operative diagnosis of an intradural lumbar disc herniation.

Intradural Lumbar Disc Herniation: Updated Report of a Case with Literature Review

Intradural lumbar disc herniation is a rare complication of disc disease. The mechanism by which a herniated disc tears the dura matter remains unknown. The preoperative diagnosis of an intradural lumbar disc herniation is still difficult. We report our experience dealing with a case of intradural lumbar disc herniation at level L3/4 in a 34-year-old man. Based on current experience, we found that attachment of the ventral dura to the posterior longitudinal ligament can be a favorable factor indicating intradural lumbar disc herniation. One should pay attention to those with cauda equina syndrome, as it can thereby promptly suggest a preoperative diagnosis of intradural lumbar disc herniation. Surgeons need to avoid omitting intraoperative lesions by palpating the dura mater during surgery for suspected tumor cases.