A 58-year-old man presents with acute bilateral leg weakness, severe perineal pain, and urinary retention. MRI of the lumbosacral spine shows a large central disc herniation at L4-L5 compressing the nerve roots below the level of the conus medullaris. The structure marked **A** in the diagram (conus medullaris) is located normally at L1-L2 and is NOT compressed. Which of the following clinical findings would be MOST consistent with compression below the conus rather than at the conus level itself?