AIM:To report the results of fixed-fulcrum fully constrained reverse shoulder arthroplasty for the treatment of recurrent shoulder instability in patients with epilepsy.METHODS:A retrospective review was conducted at a single facility.Cases were identified using a computerized database and all clinic notes and operative reports were reviewed.All patients with epilepsy and recurrent shoulder instability were included for study.Between July 2003 and August 2011 five shoulders in five consecutive patients with epilepsy underwent fixedfulcrum fully constrained reverse shoulder arthroplasty for recurrent anterior shoulder instability.The mean duration of epilepsy in the cohort was 21 years(range,5-51)and all patients suffered from grand mal seizures.RESULTS:Mean age at the time of surgery was 47 years(range,32-64).The cohort consisted of four males and one female.Mean follow-up was 4.7 years(range,4.3-5 years).There were no further episodes of instability,and no further stabilisation or revision procedures were performed.The mean Oxford shoulder instability score improved from 8 preoperatively(range,5-15)to 30 postoperatively(range,16-37)(P=0.015)and the mean subjective shoulder value improved from 20(range,0-50)preoperatively to 60(range,50-70)postoperatively(P=0.016).Mean active forward elevation improved from 71°preoperatively(range,45°-130°)to 100°postoperatively(range,80°-90°)and mean active external rotation improved from 15°preoperatively(range,0°-30°)to 40°(20°-70°)postoperatively.No cases of scapular notching or loosening were noted.CONCLUSION:Fixed-fulcrum fully constrained reverse shoulder arthroplasty should be considered for the treatment of recurrent shoulder instability in patients with epilepsy.