<unk>  is a loss of sensation<unk>  restricted to the area of the buttocks, perineum and inner surfaces of the thighs. It is frequently associated with the spine-related injury cauda equina syndrome. It is also seen in conus medullaris, the difference is that it is symmetrical in conus medullaris and asymmetric in cauda equina. It may also occur as a temporary side-effect of a sacral extra-dural injection:
Saddle anesthesia
Balanced anesthesia
Microshock
Total intravenous anaesthesia
Tumescent anesthesia
Acoustic shock
Local anesthesia
Intravenous regional anesthesia