A periglenoid labrum cyst is a swelling around the glenoid labrum of the shoulder joint, usually formed by a tear in the labrum and encapsulated by joint fluid, and can occur anywhere around the articular labrum. The presence of a cyst is usually detected by MRI. By nature, cysts do not cause pain, but are primarily caused by a tear of the glenoid labrum. We can treat this with a minimally invasive arthroscopic procedure that focuses on repairing the glenoid labral tear. Untreated glenoid labral tears can progress from small cysts to large cysts over time and compress important nerves around the joint, causing pain and decreased muscle strength, most often affecting the suprascapular nerve, for example, a posterior glenoid labral tear can compress the nerve at the glenoid notch of the scapula, while an SLAP injury can compress the nerve at the suprascapular notch, with secondary suprascapular nerve palsy following nerve compression. A tear of the inferior glenoid labrum causes an underlying cyst that compresses the axillary nerve, leading to a weakening of the lesser circular muscle and causing quadrilateral foramen syndrome. Nerve compression is an indication for surgical treatment. During minimally invasive arthroscopic surgery, the torn glenoid labrum is repaired, the compressed nerve is decompressed, and the cyst is removed to restore anatomic structure for symptom relief.