Paeoniflorin adjunct to scar release surgery for postoperative anorectal stenosis: a randomized controlled trial
In brief
Adding paeoniflorin raises 6-month stricture relief to 91%
In a multicenter RCT of 106 patients, scar-release surgery plus local paeoniflorin achieved a 90.6% stricture-relief rate at six months versus 73.6% with surgery alone, and patients reported near-normal defecation scores. Scar thickness was lower and recurrence fewer, though the trial was small and follow-up limited, so larger studies are needed.
- Journal
- Frontiers in surgery (Q2)
- Published
- 3 September 2026
- Study design
- Randomized controlled trial
- Evidence level
- Level 1, High (CEBM 1b)
- Authors
- Yuening Feng, Xi Wang, Dayong Feng, Chunhui Wang, Zhiyong Bai, Jingwen Wang, et al.
- PMID
- 42756171
- DOI
- 10.3389/fsurg.2026.1843542
Why clinicians should know about it
- Picked for Anatomy (top studies of the week, 20 September 2026).
Abstract
BACKGROUND: Postoperative anorectal stenosis is a disabling complication of anorectal surgery, characterized by fibrotic narrowing that impairs defecation and quality of life. While scar-release surgery can restore lumen patency, long-term outcomes are undermined by recurrent fibrosis. Paeoniflorin, the active component of Shaobei Injection, is a promising botanical antifibrotic agent that may enhance perioperative efficacy. This study aims to evaluate whether combining Paeoniflorin with longitudinal scar-release surgery improves anatomical and functional outcomes in patients with postoperative anorectal stenosis compared to surgery alone. METHODS: In this prospective, multicenter randomized controlled trial (Trial registration: ChiCTR2200062631) in China. Eligible patients with iatrogenic fibrotic anorectal stenosis were randomized equally (1:1) to receive either scar-release surgery plus Paeoniflorin (experimental group) or surgery alone (control group). The primary endpoints were stricture relief rate (defined as anal canal diameter ≥20 mm) and improvement in defecation difficulty score at 1 and 6 months. Secondary outcomes included anal pain (VAS), scar tissue thickness (imaging), and stricture recurrence rate. All patients were followed for 6 months. RESULTS: A total of 128 patients were enrolled and randomized (64 per group); after excluding 22 patients lost to follow-up, 106 patients (53 per group) completed the 6-month follow-up and were included in the final analysis. At 6 months, the stricture relief rate was significantly higher in the experimental group compared to the control group (90.6% vs. 73.6%; P < 0.05; RR, 1.23; 95%CI, 1.03-1.48). Mean defecation difficulty scores improved significantly in both groups, but the experimental group maintained near-normal scores (0.70 ± 0.27 at 1 month and 0.78 ± 0.17 at 6 months) compared to the control group (2.23 ± 0.88 and 2.34 ± 0.51, respectively; P < 0.05 for both time points). Secondary outcomes including reduced scar thickness and lower recurrence rates (3.8% vs. 13.2%, P = 0.08; RR, 0.29; 95%CI, 0.06-1.31) further favored the combined therapy. No injection-related adverse effects were observed. CONCLUSIONS: These preliminary 6-month findings suggest that local paeoniflorin may provide exploratory benefits as an adjunct to scar-release surgery. Larger, longer-term trials are required to validate its clinical efficacy and durability. CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn/, ChiCTR2200062631.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.