Chapter 7 Suprascapular Nerve
The Suprascapular Nerve
• The suprascapular nerve arises from the upper trunk of the brachial plexus, in close proximity to the anterior and posterior divisions (Figure 7-1). It receives fibers primarily from the C5 and C6 spinal nerves (Figure 7-2). The suprascapular nerve supplies the supraspinatus and infraspinatus muscles and the shoulder joint.
• Both muscles are important to shoulder function, the supraspinatus to initiate abduction and the infraspinatus to initiate external rotation. If elbow flexion is achieved after surgery, the patient will have difficulty in bringing food to the mouth if suprascapular function is not also regained.
• In the posterior triangle of the neck, the suprascapular nerve leaves the brachial plexus close to the lateral border of the scalenus medius.
• The suprascapular nerve passes laterally and downward and across the posterior triangle of the neck. It runs superior to the brachial plexus. The suprascapular nerve passes though the suprascapular notch under the transverse scapular ligament to descend deep to the supraspinatus and infraspinatus muscles (Figure 7-3).
• During an anterior approach, the inferior belly of the omohyoid can be used as a guide to the suprascapular notch, because that is the point of insertion of the inferior belly of the muscle.
