Spinoglenoid notch cyst: An unusual cause of atrophy – A case report and literature review

Introduction

Spinoglenoid notch cysts are an uncommon clinical-pathologic entity that can result in suprascapular nerve compression and subsequent muscle atrophy, abnormal shoulder movements, and function. Although often seen in association with labral tears, cysts may occur independently and can mimic other more common shoulder problems, resulting in diagnostic dilemmas.

Case presentation

A 24-year-old male attended the Orthopedic outpatient department with the complaint of decreased movements and weakness in his right shoulder. MRI showed the presence of a well-defined, lobulated ganglion cyst at the Spinoglenoid notch with associated edema and moderate-grade muscle atrophy in the infraspinatus and teres minor, suggesting compressive neuropathy over the suprascapular nerve. Although surgical decompression is the conventional approach, successful symptom control and functional recovery were obtained by aspiration of the cyst plus steroid injection with an ultrasound-guided procedure.

Management and outcome

The patient underwent the procedure in the left lateral decubitus position with sterile preparation and draping. A 16-G LP (16-gauge lumbar puncture needle) was used to aspirate a few millimeters of gelatinous cyst fluid. 2 ml of Bupivacaine (0.5 %), followed by the injection of Depo-Medrol (40 mg), was made into the cyst. There were no adverse effects, and the patient tolerated the procedure very well.

Conclusion

The case emphasizes the need for including Spinoglenoid notch cysts in the differential diagnosis of shoulder pain and muscle atrophy without known etiology. Surgery is the most commonly recommended intervention, but percutaneous ultrasound-guided aspiration may be a good alternative treatment option.