Abstract
INTRODUCTION AND IMPORTANCE: For patients with locally advanced low rectal cancer (LARC) unresponsive to neoadjuvant chemoradiotherapy, achieving functional sphincter preservation remains a major challenge due to tumor invasiveness and complex anal reconstruction requirements. CASE PRESENTATION: A 67-year-old female with LARC underwent extended radical resection involving anal sphincter/puborectalis muscle excision and partial vaginal wall resection. Anal reconstruction was performed via a free left gracilis myocutaneous flap routed in a "γ-shaped" configuration. Postoperatively, an individualized intensive biofeedback electrical stimulation regimen was implemented. After 2 months of training, the patient's anal function had significantly improved, as evidenced by the results of the anorectal manometry (pre-training vs. post-training resting pressure: 24.7 vs. 59.4 mmHg; contraction pressure: 35.1 vs. 434.0 mmHg). As a result, stoma reversal was successfully achieved, and the patient's postoperative anal function is now good (Williams A, Wenxer score 8). CLINICAL DISCUSSION: Gracilis muscle transplantation provides a viable option for sphincter reconstruction in LARC. Compared with conventional regimens, individualized intensive biofeedback electrical stimulation regimen can not only promote muscle fiber transformation but also significantly improve muscle contraction strength and endurance, addressing the limitations of traditional methods. CONCLUSION: This case highlights the efficacy of gracilis muscle transplantation for sphincter reconstruction and underscores the critical role of tailored biofeedback electrical stimulation in enhancing gracilis muscle contractility and endurance, and promoting anal function recovery. Our findings suggest that this multimodal approach offers a viable strategy for achieving functional sphincter preservation in low LARC, potentially improving long-term quality of life.