Fig. 1. Intensity of motor blockade expressed as percentage of the population presenting with a modified Bromage scale score of 1 (complete motor blockade), 2 (almost complete motor blockade: the patient is able only to move the feet), 3 (partial motor blockade: the patient is able to move the knees), 4 (the detectable weakness of hip flexion: the patient is able to raise the leg but is unable to keep it raised), 5 (no detectable weakness of hip flexion: the patient is able to keep the leg raised during 10 s at least); or 6 (no weakness at all: the patient is able to perform partial knee bend while supine) at different times in patients having received ( A ) bupivacaine 8 mg (n = 30; group 1), ( B ) ropivacaine 8 mg (n = 30; group 2), ( C ) ropivacaine 10 mg (n = 30; group 3), ( D ) ropivacaine 12 mg (n = 30; group 4), or ( E ) ropivacaine 14 mg (n = 30; group 5). *Significantly different from group 1, bupivacaine 8 mg.