OBJECTIVES: Rotator cuff tendinitis (RCT) is a tendon inflammation often following subacromial impingement syndrome. One of the non-surgical management modalities for RCT is subacromial injection of corticosteroids. Some studies have claimed a correlation between ACTH (Adrenocorticotropic Hormone) deficiency and rotator cuff lesions
hence, intramuscular ACTH analogue injection has been recommended as an option. This research aimed to compare the effectiveness of these two treatment methods. METHODS: We conducted a study with 86 patients suffering from RCT. The patients were randomly divided into two groups of 43
one group received a subacromial injection of 40 mg of triamcinolone acetonide, while the other group received 1 mg of intramuscular tetracosactide injection. We recorded the Constant-Murley (CM) and visual analogue scale (VAS) scores for each patient before and 4 weeks after injections to measure pain acuity and joint functionality. Later, we compared and analysed the two scores in each group. RESULTS: Based on the statistical analysis, the mean ages of the participants in the triamcinolone and tetracosactide groups were 53.21 ± 11.37 and 54.56 ± 11.98, respectively. Both groups demonstrated an improvement in VAS for pain and CM scores ( CONCLUSION: Although both treatment methods exhibit promise for pain relief, subacromial injection of triamcinolone appears more efficacious than intramuscular injection of tetracosactide in patients with RCT, based on a 4-week follow-up. TRIAL REGISTRATION: Iranian Registry of Clinical Trials, https://irct.behdasht.gov.ir, IRCT20240110060673N1.