Patients will be randomized into two groups: U (n = 25), in whom regional blockade was performed using US-guidance; and C (n = 25), in whom regional block was performed using the traditional method. Patients will be randomly assigned on a one-to-one ratio. Randomization will be performed by means of a computer generated random-numbers table. Group allocation will be concealed in sealed opaque envelopes that will not opened until patient consent had been obtained.