All of the following are clinical features of conus medullaris, EXCEPT:
Conus medullaris syndrome is associated with early bladder dysfunction. Early bladder dysfunction of conus medullaris syndrome occur due to the destruction of neurons at S2-S4 levels of the spinal cord. In this condition bladder remains areflexic. Tapered end of the spinal cord seen at the level of interveebral disk between L1 and L2 is called conus medullaris. It consist of sacral spinal cord segments. It provides innervation to the saddle area, motor innervation for sphincters and parasympathetic innervation for bladder and lower bowel. Conus medullaris sydrome is an injury of sacral cord and lumbar nerve roots within the spinal canal. Features of conus medullaris syndrome: Early disturbance of urination, defecation and sexual dysfunction with sphincter weakness. A dissociative sensory deficit is seen in the lower three or four sacral segments and the coccygeal area or hypesthesia to all sensory modalities in this region (saddle anaesthesia). Mixture of upper and lower motor neurone paralysis with absence of tendon reflexes but extensor plantar response.
Late bladder involvement
Extensor plantar
Sacral anaesthesia
Lower sacral and coccygeal involvement