Comparison of Postoperative Analgesic Efficacy of Interscalene and Suprascapular Blocks Used in Arthroscopic Shoulder Surgery

The innervation of the shoulder joint is provided by the axillary, musculocutaneous, subscapular, and suprascapular nerves, all of which originate from the brachial plexus. The suprascapular nerve passes through the suprascapular notch on the superior border of the scapula and supplies motor branches to the rotator cuff muscles. Suprascapular nerve block is widely used in the management of shoulder pain.

Regional anesthesia techniques are among the most effective methods for postoperative analgesia. Peripheral nerve blocks, a subtype of regional anesthesia, are particularly suitable for postoperative pain control in shoulder surgeries due to their ability to provide long-lasting and effective analgesia, reduce opioid requirements and related side effects or dependency, and facilitate recovery by promoting early functional restoration.Interscalene brachial plexus block (ISB) is commonly used for analgesia in shoulder surgery and is considered the gold standard technique. However, ISB also blocks the phrenic nerve (C3-C5), which may result in ipsilateral hemidiaphragmatic paresis (HDP). This can cause respiratory complications, particularly in patients with preexisting pulmonary disease, obstructive sleep apnea, or morbid obesity.

The suprascapular nerve block (SSB), applied at a more distal level of the brachial plexus, preserves the phrenic nerve and thus minimizes the respiratory side effects associated with ISB.

Inclusion criteria

• Patients who have provided written informed consent
• Patients over 18 years of age scheduled for elective shoulder arthroscopy
• Patients classified as ASA I-II
• Patients undergoing general anesthesia

Exclusion criteria

• Patients undergoing shoulder surgery other than arthroscopic procedures (e.g., revision or open surgery)
• Patients with pre-existing respiratory, cardiac, renal, neurological, or hepatic diseases
• Presence of neuropathy affecting the brachial plexus
• Contraindications to peripheral nerve block (e.g., coagulopathy)
• Known allergy to local anesthetics