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

Comparison of the Analgesic Effects and Side Effects of Interscalene and Suprascapular Blocks for Pain Control Following Arthroscopic Shoulder Surgery

The Importance of Postoperative Analgesia in Shoulder Surgery

Shoulder surgery is an orthopedic procedure that can be performed either through open surgery or arthroscopically. Pain following shoulder surgery can lead to adverse outcomes such as decreased functional status, increased consumption of narcotic analgesics, and the development of chronic pain.

Therefore, achieving optimal postoperative shoulder analgesia is important not only for patient comfort and satisfaction but also for promoting functional recovery, preventing chronic pain, and reducing the need for narcotic analgesics. Additionally, minimizing the side effects associated with nerve block techniques used for analgesia is crucial for the overall success of the treatment.

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:

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

Exclusion Criteria:

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