The suprascapular nerve is the nerve to the rotator cuff. The suprascapular nerve runs in the back of the shoulder, where it can be compressed. This is effectively the ‘carpal tunnel syndrome of the shoulder’, although it’s nowhere near as common.
Suprascapular nerve compression leads to pain in the back of the shoulder, weakness and eventually atrophy of the rotator cuff muscles. It is often overlooked, but once the rotator cuff muscles atrophy, the damage and weakness may be permanent. Diagnosis is obtained through physical examination and a nerve conduction study/EMG. Suprascapular nerve compression can be due to compression under one of two ligaments (the transverse scapular ligament and/or the spinoglenoid ligament), similar to how carpal tunnel syndrome is caused by compression of the median nerve underneath the transverse scapular ligament. It may also be caused by a ganglion cyst from by a SLAP (labral) tear in the shoulder joint.
If the suprascapular nerve compression is caused by a ganglion cyst, it can be effectively treated by arthroscopically repairing the SLAP lesion; details are provided in the “SLAP Lesion” section of this website. In these cases, the ganglion cyst itself does not usually need to be removed; repairing the SLAP lesion resolves it.
If the suprascapular nerve is compressed under a ligament, most commonly the transverse scapular ligament, this can be treated by cutting that ligament. This is analogous to releasing the compressive ligament during a carpal tunnel release. While traditionally, cutting the transverse scapular ligament has been performed by an open surgical approach, this can now be safely and effectively performed arthroscopically. This is an outpatient procedure. A before and after view is pictured here:
Arthroscopic view of the needle about to cut the transverse scapular ligament, the off-white structure that looks like a fence immediately behind the needle (the metal object going from top to bottom in the middle of the photograph).
The transverse scapular ligament (white structure that is now flapped back) has been cut and the nerve (the yellow, cord-like structure) is now decompressed.
If arthroscopic suprascapular nerve decompression is performed as an isolated procedure there are no post-operative restrictions, other than to keep the arthroscopic portals clean and dry for 3 days. Activities are limited only by pain and discomfort.
In summary, suprascapular nerve compression is an often over-looked cause of pain, weakness and permanent rotator cuff muscle atrophy in the back of the shoulder. And it can now be effectively treated arthroscopically on an outpatient basis.