Lower sacral (S2, S3, S4) nerve root test – the same roots that supply saddle sensation also supply sphincter function and sensation to the rectum and bladder.

Indication

Procedure

Test sensation in the mid-line between the upper buttocks

  1. Start with a place you can feel sensation (#1) → scratches

  2. Move across the upper buttocks (#2)→ see if they loss sensation around the midline

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If history and physical examination are suggestive of !CES - Cauda Equina Syndrome , perform a DRE to assess for resting and active sphincter tone, the latter by asking the patient to ‘bear down’ against your finger