Levels of sensory and motor blockade will be recorded just prior to skin prep, following arrival in recovery room and then every 30 minutes thereafter. Sensory block will be monitored by dermatome level at which there is a loss of sensation to ice. Motor blockade will be checked using the modified Bromage score (0 = no impairment, 1 = unable to raise extended legs but able to move knees and ankles, 2 = unable to raise extended legs or to flex knees but able to move feet, 3 = unable to flex ankles, knees or hips).