ObjectiveTo investigate the curative effect of C-shaped mucosal resection and anastomosis above the dentate line in the treatment of mixed hemorrhoids and its effect on anal function. MethodsA total of 78 patients with degree Ⅳ mixed hemorrhoids treated in Nanjing Liuhe District People’s Hospital from June 2015 to February 2018 were retrospectively collected. The patients were divided into control group (n=39) and observation group (n=39) according to treatment methods. Patients of the control group received traditional procedure for prolapse and hemorrhoids operation, while patients of the observation group received C-shaped mucosal resection and anastomosis above the dentate line. The perioperative indexes (operation time, intraoperative blood loss, hospital stay, etc.), subjective function evaluation indexes (Wexner constipation score, Kirwan grade, etc.), clinical efficacy and recurrence rate were compared between the two groups. The random walking model was used to evaluate the clinical curative effect. ResultsThe intraoperative blood loss [(27.9±3.4) mL vs. (43.2±5.2) mL, P<0.001], 24 h visual analogue scale score [(4.2±1.5) points vs. (5.6±1.5) points, P<0.001], duration of first defecation pain [(22.1±3.2) min vs. (34.2±5.0) min, P<0.001], the time of carrying blood [(4.1±0.4) d vs. (5.7±0.6) d, P<0.001], and the time of edema [(3.2±0.6) d vs. (4.7±0.9) d, P<0.001] in the observation group were shorter (lower) than those in the control group. The difference between pre-and post-operation of Wexner constipation score [(13.2±2.4) points vs. (11.7±2.1) points, P=0.004], resting pressure [(23.1±4.9) mmHg vs. (17.8±3.4) mmHg, P<0.001] and maximum squeeze pressure [(33.5±7.3) mmHg vs. (23.1±5.6) mmHg, P<0.001] in the observation group were significantly higher than those in the control group. There was a long-term correlation between changes in random fluctuating power rate values of Wexner constipation score, Kirwan grade, rectoanal inhibitory reflex positive rate, resting pressure, maximum squeeze pressure and the surgical procedure received by the patient of the two groups. The total effective rate [97.4% (38/39) vs. 66.7% (26/39)] and non-recurrence rate [92.3% (36/39) vs. 76.9% (29/39)] in the observation group were higher than those in the control group, while there was no significant difference in the incidence of total complications between the two groups [5.1% (2/39) vs. 12.8% (5/39), P=0.235)]. ConclusionCompared with PPH, C-shaped mucosal resection and anastomosis above the dentate line for the treatment of degree Ⅳ mixed hemorrhoids can improve the therapeutic effect, reduce postoperative recurrence, maintain anal function and facilitate the recovery of patients.