Background: Chronic subacromial bursitis, impingement syndrome and rotator cuff tendinitis are synonymous terms describing a clinical condition affecting from 2% to 18% of the adult population with subacromial impingement syndrome in particular being the most common disorder, resulting in functional loss and disability, of the shoulder. The research set intended to compare the efficacy of open acromioplasty to that of arthroscopic acromioplasty in treating impingement in the shoulder. Methods Forty adult patients with a clinical and imaging diagnosis of shoulder impingement from the outpatient clinic of the orthopaedic department at Banha University Hospitals participated in this prospective randomised clinical study. The patients were randomly split into two groups: Group A: 20 patients who received arthroscopic acromioplasty surgery, Group B: 20 patient who underwent open acromioplasty surgery. Results: The mean age of our patients in Group A and Group B were (42.19 ± 4.4; 40.70 ± 3.8 correspondingly) with no significant difference. Group B had longer operative and recovery times and a longer mean hospital stay than group A (p = 0.02, 0.028). In the current research, the VAS scores of both groups A and B were significantly lower after surgery compared to before surgery (P 0.001). The difference between pre- and post-operative VAS scores was also substantially larger in group B than in group A (p = 0.039). Group A had a higher ASES score at two weeks, one month, and three months post-op than group B did (p = 0.002, 0.001, and = 0.029). As far as problems go, this research found no discernible difference between the groups. In Group B, 20% of patients had post-op stiffness, and 15% experienced wound infection. Conclusion: the arthroscopic acromioplasty method was related with reduced pain, higher ASES score. A difference was identified between the 2 groups in main and secondary outcomes in the long term, no difference in the occurrence of complications. Besides, we feel that the arthroscopic acromioplasty surgery has greater recovery at short-term follow-ups.