Purpose <p>We previously reported a manipulation technique for frozen shoulder using ultrasound-guided cervical nerve root block. Although the results were excellent, we considered that the range of external rotation could be improved. In the present study, we aimed to confirm the effectiveness of our modified manipulation technique for further improving the range of external rotation at the shoulder joint.</p> Methods <p>We retrospectively searched our electronic medical records to identify patients who underwent manipulation for frozen shoulder at our institution between January 2024 and June 2024. A total of 173 shoulders of 169 patients (mean age 53.8 ± 6.9&#xa0;years) were included. Three changes were made to our previous method: a change in the method for intra-articular injection of the glenohumeral joint, addition of C7 to the nerve block, and changes in the manual manipulation technique. Range of motion (ROM) at the shoulder was measured before manipulation and at 1&#xa0;week, 1&#xa0;month, 2&#xa0;months, and 3&#xa0;months after the procedure. The results were compared with those in our previous report.</p> Results <p>Mean range of external rotation (95% confidence interval) was 11.5° (9.5–13.5, <i>p</i> = 0.51) before manipulation, 56.2° (52.9–59.5, <i>p</i> &lt; 0.001) at 1&#xa0;week, and 58.0° (53.9–62.7; <i>p</i> &lt; 0.001) at 3&#xa0;months. The results for range of external rotation were significantly better than in the previous report. There was no significant difference in ROM in terms of flexion and abduction between the two studies.</p> Conclusion <p>Range of external rotation at the shoulder joint was significantly improved by use of the revised manipulation technique.</p>