Isolated Infraspinatous Atrophy from a Spinoglenoid Cyst: A Case Report

We present a case of a 26-year-old gentleman with isolated right infraspinatus atrophy arising from a spinoglenoid cyst of the right shoulder. He presented two years following his shoulder injury and failed conservative rehabilitation alone. At initial arthroscopic surgery, a superior labral anterior to posterior (SLAP) tear was diagnosed and the spinoglenoid cyst was debrided without formal labral repair. The patient’s condition did not improve, and second arthroscopy was performed three months following the first with suture anchor repair of the labral tear and cyst decompression. Post-operative magnetic resonant imaging (MRI) scans showed complete resolution of the cyst and recovery of infraspinatus muscle bulk at six months. At final follow-up 18 months post SLAP repair, he has regained full shoulder function and has returned to recreational sports. Our case highlights the importance of proper management of SLAP tears in resolving spinoglenoid cysts by demonstrating the outcomes from two different surgical methods in the same patient.