Abstract: Objective To explore the clinical effect of arthroscopic treatment for large and massive rotator cuff tears with different acromiohumeral distance (AHD).Methods A total of 125 patients with large and massive rotator cuff tears who underwent arthroscopic treatment in Department of Orthopedics, the Affiliated Hospital of Xuzhou Medical University from January 2018 to June 2022 were selected and their clinical data were retrospectively analyzed. According to their AHD, the patient were divided into two groups: a normal AHD group (AHD≥7 mm, n=69) and a reduced AHD group (AHD<7 mm, n=56). Their pain visual analog score (VAS), Constant-Murley score, University of California at Los Angeles (UCLA) shoulder scores, American Society of Shoulder and Elbow Surgeons (ASES) scores, and the shoulder joint range of motion before surgery and one year after surgery were compared for statistical analysis. Their healing of the rotator cuff one year after surgery based on the Sugaya classification criteria of shoulder joint MRI imaging, and the incidence of rotator cuff retearing after surgery were recorded.Results A statistical difference was found in AHD values between the two groups (P<0.05). There was no statistical difference in other data (all P>0.05). One year after surgery, both groups showed significant improvement in shoulder joint range of motion compared with those before surgery (P<0.05), where the shoulder joint ranges of motion (flexion, abduction, and lateral rotation) in the normal AHD group was better than those in those reduced AHD group (all P<0 05). One year after surgery, both groups showed significant improvement in VAS scores, Constant-Murley scores, UCLA scores, and ASES scores compared with those before surgery (P<0.05), where the VAS scores, Constant-Murley scores, UCLA scores, and ASES scores in the normal AHD group was better than those in the reduced AHD group (all P<0.05). One year after surgery, MRI was reexamined, and the retearing rate was 13.0% (9/69) for the normal AHD group, and 30.4% (17/56) for the reduced AHD group, with statistical difference (P=0.018).Conclusions For patients with large and massive rotator cuff tears, patients with normal AHD present more significant pain relief after rotator cuff repair surgery than those with reduced AHD, with better shoulder joint functions and a lower incidence of rotator cuff retearing. AHD can serve as a predictive indicator of clinical efficacy after repair of large and massive rotator cuff tears.