Conus medullaris syndrome from a transdural disc herniation at the thoracolumbar junction.

摘要

An 84-year-old gentleman described a sudden twinge of back pain when getting into his car; 24 h later and whilst walking, he suffered another such twinge coupled with sudden weakness in both legs, which brought him to his knees. He recovered in minutes; but on the 3rd day, his pain started radiating to his buttocks. He developed painless urinary incontinence and perianal anaesthesia. On admission, he had normal power in his legs, an absent right ankle reflex, and reduced anal tone. His plantars were extensor. Urgent MRI showed abnormal signal in the canal at T12/L1 suggestive of a disc prolapse with a sequestrated fragment causing conus compression (Fig. 1a-c). Although sagittal imaging raised concerns about a double crush picture with further stenosis at L4/5, axial imaging at that level (Fig. 3) showed moderate canal stenosis, and it was felt that the clinical picture was in keeping with a conus medullaris syndrome.