Computed tomography of lumbosacral conjoined nerve root anomalies. Potential cause of false-positive reading for herniated nucleus pulposus.

Conjoined origin anomalies of lumbosacral nerve roots, if incorrectly interpreted, could be misdiagnosed as disc herniations on computed tomography (CT). Several characteristic CT features of these anomalies are presented that should distinguish them from herniated discs. A conjoined root anomaly was found in approximately 2% of the 8,000 lumbosacral CT scans.