Method: The patient who was admitted to our clinic with low back pain and left sciatica in a patient detected extruded disc herniation at left L4-5 level in MRI.

We did not find any pathology with standart L4 partial hemilaminectomy and foraminotomy during surgery.

Result: Exploration was continued via L4 total laminectomy and intradural extension of herniated disc was seen. Intradural disc fragments were removed under the operation microscope after the dural opening. The clinical signs of the patients improved completely in the postoperative period.

Conclusian: The mechanism of intradural disc herniation cannot be explained exactly that how intervertebral disc penetrates the dura. The possibility of intradural disc herniation must be kept in mind if the herniated disc did not seen during the standart surgical procedure. Anahtar Kelimeler : Intradural, lumbar disc herniation, surgery