Sixty-nine patients undergoing primary total shoulder arthroplasty (TSA) were randomized to receive surgery with a wound protector or standard surgery without a wound protector. The primary outcome of interest was the rate of positive deep wound cultures for Cutibacterium acnes. Secondary outcomes included soft tissue injury to the deltoid, pectoralis major, and cephalic vein, as well as operative time and estimated blood loss. Outcomes were assessed with culture swabs obtained after final implantation and tissue injury graded using a modified Tscherne classification scale. Overall, the results of the study revealed that the wound protector group had significantly fewer positive C. acnes cultures compared with the control group (1/34 vs 9/35, p=0.007). Additionally, deltoid and pectoralis muscle injury scores were significantly lower in the wound protector group (p<0.001 for both), while surgical time and blood loss were not significantly different. These findings suggest that wound protector use may reduce bacterial colonization and soft tissue injury during TSA.