A new nerve block procedure for the suprascapular nerve based on a cadaveric study

Abstract

Hypothesis: Shoulder pain after rotator cuff repair surgery is sometimes very severe. Suprascapular nerve block (SSNB) is a method used to relieve this shoulder pain, but is not always completely effective. The purpose of this study is to develop the new effective suprascapular nerve block procedure.

Methods: To obtain an effective SSNB, we investigated an anatomic lesion of the sensory branches of the SSN in 8 cadavers and developed a new procedure. We evaluated its effectiveness by recording visual analog scale (VAS) scores in 8 patients experiencing severe pain after rotator cuff repair surgery before SSNB and for up to 24 hours postoperatively.

Results: All cadaver shoulders had 2 or 3 sensory branches that just passed the scapular notch. The branches originated from the SSN, pursued the base of the coracoid process, perforated the supraspinatus muscle, and extended toward the subacromial bursa. The average VAS score of the 8 patients postoperatively was 5.4 +/- 2.7 before SSNB and improved to 2.8 +/- 1.6 immediately after SSNB, to 1.2 +/- 0.6 at 1 hour, and to 0.8 +/- 0.8 at 4 hours. Effective pain control was achieved, and SSNB presented no complications.

Conclusion: Our SSNB method is safe and effective for pain control in patients after open cuff repair. We expect it will be a useful management tool for pain relief after rotator cuff repair in the future.

Level of evidence: Basic science study.