Suprascapular Blocks

Trends are evolving in decreasing intraoperative and postoperative opioid use.  Therefore, anesthesiologists are constantly learning new regional techniques to help with postoperative pain.  For shoulder surgeries, I’ve moved away from interscalene blocks toward supraclavicular blocks.  I think the interscalene block provides a better block of a total shoulder surgery, however, certain patient comorbidities often make the supraclavicular block a better choice.

Nice paper from Anesthesiology, Dec 2017: Suprascapular and Interscalene Nerve Block for Shoulder Surgery: A Systematic Review and Meta-analysis. Anesthesiology 12 2017, Vol.127, 998-1013.

Nowadays, it seems that suprascapular blocks are gaining in popularity (I’d probably use it to supplement the supraclavicular block.

Supplies and Technique (from USRA):

• After skin and transducer preparation, place a linear 38-mm high frequency 10-12 MHz transducer on the scapula to obtain a best possible transverse view of the suprascapular nerve (SSN) and suprascapular vessels.
• Ask the patient to place the hand over to the contralateral shoulder. This will move the scapula laterally to provide more space for SSN scanning. Also, this will move the target SSN injection site more laterally away from the thorax.
• Place one end of the transducer over the scapular spine and the other end directing towards the coracoid process.
• With the patient sitting up, a 22 G, 8 cm needle is advanced to penetrate the trapezius and supraspinatus muscles until the needle is positioned immediately next to the SSN and SSA.
• The optimal needle endpoint is reached when the needle tip is positioned underneath the fascia of the SSM.
• **CAUTION** : Avoid targeting the SSN in the suprascapular notch because accidental anterior needle advancement can puncture the pleura anteriorly. 
• The goal is to first inject local anesthetic deep to the fascia of the SSM. A total of 5-8 mL of local anesthetic is usually sufficient to block the SSN

Suprascapular Nerve

How to position the ultrasound probe:

From USRA

Ultrasound Image

From USRA.  SSM = supraspinatus muscle
SSA = suprascapular artery
SSN = suprascapular nerve
TZM = trapezius muscle
STSL = superior transverse scapular ligament

Useful Links

• ASRA: suprascapular and axillary combined block
• USRA
• James Cook Regional Anesthesia Course

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Update: June 19, 2018

Comparison of Anterior Suprascapular, Supraclavicular, and Interscalene Nerve Block Approaches for Major Outpatient Arthroscopic Shoulder Surgery: A Randomized, Double-blind, Noninferiority Trial. Anesthesiology 7 2018, Vol.129, 47-57.

From Anesthesiology, July 2018

• Conclusions: The anterior suprascapular block, but not the supraclavicular, provides noninferior analgesia compared to the interscalene approach for major arthroscopic shoulder surgery. Pulmonary function is best preserved with the anterior suprascapular nerve block.