Intradural lumbar disc herniation associated with degenerative spine disease and rheumatoid arthritis.

STUDY DESIGN A case report. OBJECTIVE To demonstrate a case of intradural lumbar disc herniation including imaging studies, intraoperative imaging, and an intraoperative video. SUMMARY OF BACKGROUND DATA The first case of lumbar intradural disc herniation was reported as early as 1942; since then more than 150 cases have been reported, mostly in the lumbar spine. Gadolinium-enhanced magnetic resonance image (MRI) is considered the "gold standard" for diagnosing this entity, although it is rarely performed routinely in lumbar disc disease and diagnosis is often made intraoperatively. METHODS A 70-year-old man presented to the emergency department as a referral complaining of lower back pain, loss of sensation in the right thigh, and difficulty walking. On examination, he showed uneven gait, right-sided foot drop (1/5), hypesthesias in the right inguinal area and ventral thigh, and a positive straight leg raise test on the right. Anal sphincter tone was within normal limits. A magnetic resonance image of the lumbar spine showed a large mediolateral herniated disc at L3-L4, with caudal displacement and unclear signal changes intradurally. RESULTS Intraoperatively, the herniated disc was found upon opening the dural sac. CONCLUSION Intradural disc herniations are a rare entity. The opening and inspection of the dural sack should be considered when the correct spinal level can be confirmed and insufficient herniated disc material can be visualized extradurally.