 Total studied group n = 100  Test K  P Value  
B n = 25  BF n = 25  BC n = 25  BN n = 25  
Duration of analgesia (min) 






Mean ± SD  60.00 ± 11.70  72.60 ± 13.93  238.00 ± 125.79  67.40 ± 15.42  53.42  <0.001HS 