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86 m a s s a g e & b o d y w o r k m a y / j u n e 2 0 1 7 technique SCIENCE OF NERVES Shouldering the Challenge of Suprascapular Neuropathy By Whitney Lowe The shoulder is the most mobile joint in the body. The challenge with such extensive mobility, however, is that mechanical support and function relies heavily on the soft tissues. Consequently, there are more soft-tissue disorders in this region. Bursitis and rotator cuff pathology are common diagnoses for soft- tissue shoulder pain. While both of these occur, other conditions can mimic these more common complaints. In situations like this, treatments may be ineffective because they target the wrong cause. Damage or impairment to the suprascapular nerve can easily mimic a number of other shoulder complaints. Because of the location and function of this nerve, massage therapy can be a beneficial means of addressing suprascapular nerve disorders. Let's take a look at the structure and function of this nerve, which often get ignored in the evaluation and treatment process. ANATOMY The suprascapular nerve is a relatively small and short nerve. Unfortunately, it has to bypass several anatomical obstacles along its path and these obstacles are what make the nerve vulnerable to compression and tension injury. The suprascapular nerve originates from the C5 and C6 nerve roots and is a mixed nerve, meaning it carries both motor and sensory fibers. It provides sensory innervation to the posterior and lateral aspect of the shoulder and motor innervation to the supraspinatus and infraspinatus muscles. The main portion of the nerve begins where it branches off the superior trunk of the brachial plexus in the cervical region (Image 1). It branches off the brachial plexus relatively high up along the bundle of nerves so it is less susceptible to a number of the other compression pathologies that affect lower portions of the brachial plexus. After branching off the superior trunk of the brachial plexus, the nerve travels across the top of the shoulder on its way to the superior and lateral aspect of the scapula. The first primary anatomical obstacle it encounters is the narrow passage through the suprascapular notch (Image 2). The edges of the scapula along the suprascapular notch can be somewhat sharp and they may cause damage to the nerve when it is pulled taut against the edge of the notch. There is a small ligament that spans the opening at the top of the suprascapular notch. This ligament is called the superior transverse scapular ligament. Because it spans the opening of the suprascapular notch, it essentially creates a small foramen the nerve must travel through (Image 2). The superior transverse scapular ligament can sometimes become ossified, creating an even more rigid border for this narrow channel that the nerve passes through. 1 There is also some indication that the suprascapular notch may narrow with aging. 2 Ligament ossification and narrowing of the opening at the suprascapular notch are both contributing factors to suprascapular nerve compression. After the nerve courses through the suprascapular notch, branches extend out that innervate the supraspinatus muscle. Some of the remaining branches that pass the spine of the scapula and go down to the infraspinatus region may actually pass through the supraspinatus muscle; this is another potential site of nerve entrapment. 1 2 The suprascapular nerve and its origin from the brachial plexus. Image is from 3D4Medical's Complete Anatomy application. The suprascapular notch with the superior transverse scapular ligament. Image is from 3D4Medical's Complete Anatomy application. Suprascapular nerve Superior transverse scapular ligament