The patients will be randomized into 2 equal groups by a computer-generated random numbers table, named group A, B.

Group A: Patients will receive Anterior glenoid block combined with suprascapular nerve block.

Group B: Patients will receive conventional interscalene block.

In group A, the patient will be supine for anterior glenoid block.

The suprascapular nerve will be identified as it branch off from the superior trunk and will be traced until it courses beneath the inferior belly of the omohyoid muscle.

In group B, interscalene brachial plexus block will be performed.

The primary outcomes will be as follows: (1) 11-point (0-10) numeric rating scale (NRS) pain score immediately before surgery starts and after surgery; (2) degree of preserved diaphragmatic function (DPDF): the ratio of postoperative to pre-block (baseline) diaphragmatic excursion amplitude will be assessed in the holding area using a curvilinear probe (Sono Site, Transportable fuji M-turbo ultrasound system).;(3) degree of preserved handgrip strength (DPHS): the ratio of postoperative to pre-block (baseline) handgrip strength (the maximal force patients exerted when instructed to squeeze the dynamometer handles as tightly as feasible). Measurements will be done before surgery, immediately postoperative, 4, 8, and 24 hours postoperatively.

And (4) Recording of the complications which are: Hematoma, nerve injury, allergy to any of the used drugs.

Inclusion Criteria:

1. Patients American Society of anesthesiologists' physical status (ASA) I to II.
2. Aged 18 to 65 years.
3. Both sexes.
4. Patients scheduled for shoulder arthroscopy.

Exclusion Criteria:

1. Patient refusal
2. ASA physical status III or more.
3. Patients with known allergy to any of the study drugs.
4. Infection at the site of injection.
5. Patients with history of cardiovascular disease.
6. Patients with renal disease.
7. Patients with hepatic disease.
8. Patients with neuromuscular disease.
9. Presence of any coagulopathy.
10. Chronic opioid, gabapentin or pregabalin use.
11. Patients with history of any psychiatric disorder.