Inclusion Criteria:  Age: 18-65 years old. Sex: Both sexes. ASA I & II.  Exclusion Criteria:  - Patient refusal. Bleeding disorders. Damage or disease of the brachial plexus. ASA more than II. Pre-existing peripheral neuropathy. Patients with neuromuscular diseases. Patients with known hypersensitivity to drugs of the study. Patients with local skin infection at the site of injection. Psychiatric diseases interfering with evaluation of the block.