BACKGROUND: Local administration of opioids causes effective analgesia without adverse effects related to the central nervous system. After the beneficial demonstration of peripheral opioid receptors in joint synovia, intra-articular opioid injections were used for pain treatment. Clinical studies have reported the safety and efficacy of hyaluronate injection in the shoulder joint of patients with osteoarthritis, periarthritis, rotator cuff tears, and adhesive capsulitis.OBJECTIVES: To estimate the efficacy of intra-articular hyaluronate and tramadol injection for adhesive capsulitis of the shoulder compared with that of intra-articular hyaluronate injection alone.METHODS: Thirty patients with adhesive capsulitis of the shoulder were randomized to the hyaluronate group (n= 16) or the tramadol group (n= 14). Hyaluronate group members were administered five weekly intra-articular hyaluronate injections; tramadol group members were administered three weekly intra-articular hyaluronate and tramadol injections and then two weekly intra-articular injections of hyaluronate. Visual Analog Scale (VAS), passive range of motion (PROM) of the shoulder joint, and Shoulder Pain and Disability Index (SPADI) scores were assessed at baseline and weeks 1, 2, 3, 4, and 6 after the initial injection.RESULTS: A significant improvement was observed in VAS, PROM, and SPADI scores between time points in both groups. In comparison in both groups at weeks 1 and 2 after the initial injection the VAS scores of the tramadol group were significantly lower than those of the hyaluronate group.CONCLUSIONS: Intra-articular hyaluronate with tramadol showed more rapid and strong analgesic effects than intra-articular hyaluronate alone and did not induce any adverse effects.