Evidence map›Paper›PMID 41686620›Full record

Trial reportMedicine2026

The effect of methylene blue infiltrating injection on anal pain after Milligan-Morgan surgery: A randomized controlled clinical study.

Jing Zhu, Heng Deng, Ming Li, Kun Tang

Abstract readRandomized Controlled Trial
In one paragraph

Trial report in Medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Trial
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors.

Jing ZhuDepartment of Anorectal Surgery, The South District of Hefei First People's Hospital, Hefei Binhu Hospital, Hefei, China.
Heng DengDepartment of Proctology, The Second Hospital Affiliated Anhui University of Chinese Medicine, Hefei, China.ORCID 0000-0002-2199-8960
Ming LiDepartment of Proctology, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, China.
Kun TangDepartment of Proctology, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, China.

Funding

Scientific Research Project of Colleges and Universities of Anhui Province 2023AH050848
6 · The paper itself

Abstract

backgroundTo investigate the efficacy and safety of methylene blue infiltrating injection (MBI) in alleviating postoperative pain following hemorrhoidectomy.

methodsIn a randomized clinical trial, 60 patients with mixed hemorrhoids undergoing Milligan-Morgan surgery were divided into 2 groups: a study group (n = 30) and a control group (n = 30). Upon surgical completion, patients in the study group received an intraoperative MBI to the surgical incisions. All patients, in both groups, then received the same standard postoperative on-demand intravenous lornoxicam protocol. The primary outcome was anal pain intensity assessed by the visual analog scale scores at 6, 24, 48, and 72 hours. Secondary outcomes included limb movement score, incision edema, duration of the first postoperative defecation, supplemental analgesic consumption, length of hospital stay, hospitalization costs, and serum levels of substance P, 5-hydroxytryptamine, and prostaglandin E2.

resultsNo significant differences were observed in baseline characteristics. The study group exhibited significantly lower visual analog scale scores at all time points (all P < .001) and required substantially less supplemental lornoxicam (22.67 ± 17.01 mg vs 56.80 ± 9.32 mg, P < .001). Patients in the study group also had better limb movement scores, less incision edema, a shorter duration of the first postoperative defecation, a reduced hospital stay, and lower medical costs (P < .01). Serum levels of substance P, 5-hydroxytryptamine, and prostaglandin E2 were significantly lower in the study group (all P < .05). No perianal cellulitis, skin necrosis, or thrombosis occurred in either group.

conclusionMBI provides effective and safe analgesia after Milligan-Morgan surgery, significantly reducing pain, analgesic consumption, hospital stay, and cost.

Indexed as

HemorrhoidectomyHemorrhoidsMethylene BluePostoperative PainAdultAnal CanalAnalgesicsAnti-Inflammatory Agents, Non-SteroidalFemaleHumansLength of StayMaleMiddle AgedPain MeasurementPiroxicamTreatment OutcomeAnalgesicsAnti-Inflammatory Agents, Non-SteroidallornoxicamMethylene BluePiroxicammethylene bluemixed hemorrhoidspain managementrandomized controlled trial

Identifiers

PMID41686620
PMCPMC12908747

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.