Suprascapular nerve palsy

April 28th, 2007

While shoulder weakness may reflect the presence of a rotator cuff tear, the nerve that normally innervates the supraspinatus and infraspinatus cuff muscles may be the source of the problem.

The Suprascapular nerve can be pinched during its course through the scapular foramen by the transverse scapular ligament, which may ossify-- or a ganglion cyst on the top surface of the glenoid may place pressure on the nerve.

Nerve conduction studies and an MRI are typically checked to confirm the diagnosis. The prevailing opinion about operative intervention is the following:

1. In the absence of any type of cyst on the MRI, treatment should be nonoperative--physical therapy,for 6 months, prior to considering open nerve exploration and release of the transverse scapular ligament.

2. If a supraglenoid cyst is identified, arthroscopic decompression may be successful in the majority of cases, thus it makes good sense to try this option relatively soon after diagnosis.

3. If recovery after arthroscopic treatment is not favorable, open nerve decompression is an option, but functional outcomes may be unsatisfactory if suprascapular nerve palsy has been present for 12 months or greater because of irreversible muscle atrophy.

Related Photos:

Preoperative MRI image shows supraglenoid ganglion cyst

Supraspinatus and Infraspinatus muscle atrophy reflect Suprascapular nerve palsy

This illustration shows the transverse scapular ligament (encircled).

Full recover resulted by 6 months after arthroscopic intervention