Additional intraoperative subpectoral plane block vs conventional pain control: A comparison of shoulder movement in patients with mastectomy.

PURPOSE: Shoulder pain is common among mastectomy patients, with limiting shoulder mobility and negatively affecting their quality of life. Pectoral nerve blocks (PECs) have demonstrated efficacy in providing postoperative analgesia. We hypothesized that these nerve blocks could improve shoulder movement in patients undergoing mastectomy.

METHODS: This prospective, randomized, double-blind controlled trial enrolled female participants diagnosed with breast cancer and scheduled for mastectomy. Participants were randomly assigned to either the conventional analgesia group or the intervention group. In the intervention group, a PECs II block was applied prior to skin closure following a mastectomy. This study's primary outcome was the assessment of shoulder movement ratios in 5 different positions (forward elevation, external rotation, arm abduction, internal rotation, and cross-body adduction), which were recorded before surgery, at 24-h, 48-h, and 72-h intervals postoperatively, with follow-up at 1 month, 2 months, 3 months, and 6 months.

RESULTS: A total of 59 participants were included in the final analysis. Patients who underwent mastectomy with PECs II block exhibited better shoulder movement in terms of external rotation and arm abduction from the early post-surgery up to 6 months postoperatively. Shoulder forward elevation also showed superior gains during the early postoperative period, with statistical significance observed after 1 month following the surgery. However, no significant differences were found between the two groups in terms of internal rotation and adduction movements of the shoulder.

CONCLUSIONS: Compared to conventional analgesia, intraoperative pectoral nerve block under direct vision enhances shoulder mobility in forward elevation, external rotation, and arm abduction after mastectomy in breast cancer patients.