Evidence for subacromial balloon spacers in massive irreparable rotator cuff tears is surprisingly thin—only two RCTs exist, both published in 2022, and they don’t agree. One trial (Metcalfe et al.) tested the balloon against simple debridement and actually found debridement performed better. The other (Verma et al.) compared the balloon to partial repair and concluded it wasn’t inferior, with similar functional gains and a shorter operative time. The problem is that the trials differed in design, control procedures, patient selection, and methodological approach, making their results difficult to combine or interpret collectively. With such limited and inconsistent RCT data, it’s too early to know who—if anyone—truly benefits from a subacromial spacer. More rigorous, head-to-head studies are needed before drawing firm conclusions.