Plantar Needle-pricking for Early Lower-Limb Recovery After Stroke via the Nociceptive Withdrawal Reflex: Assessor-Blinded Randomized Trial

Summary

An assessor-blinded randomized trial in post-stroke flaccid hemiplegia (Brunnstrom I) tested plantar needle-pricking to evoke nociceptive withdrawal reflexes. After six days of treatment plus standardized rehabilitation, more participants progressed beyond stage I (12/38 vs. 3/38 controls), with greater Brunnstrom stage change (P = 0.013).

Abstract

This assessor-blinded randomized controlled trial evaluated whether a standardized plantar needle-pricking protocol designed to evoke the nociceptive withdrawal reflex (NWR) improves early lower-limb motor recovery in post-stroke flaccid hemiplegia. Eighty patients were randomized (1:1) to receive either NWR-evoking plantar needle-pricking plus standardized rehabilitation or standardized rehabilitation alone for 6 consecutive days; 76 participants completed outcome assessments (38 per group). Primary outcomes were Brunnstrom stage and the Fugl-Meyer Assessment of the Lower Extremity (FMA-LE). By day 6, the pricking group demonstrated a greater shift in Brunnstrom stage distribution (P = 0.03; Cramér's V = 0.31, 95% CI 0.14-0.48) and a larger median Brunnstrom stage change from baseline (1 [0-1] vs. 0 [0-1]; P = 0.013; effect size r = 0.29, 95% CI 0.06-0.48). FMA-LE total score at day 6 was higher in the pricking group (16 [12-19] vs. 11 [8-14]; P < 0.01; effect size r = 0.38, 95% CI 0.17-0.56). Secondary outcomes favored the pricking group for lower-limb active range of motion, manual muscle strength, and knee flexor tone (all P < 0.05). Outcome assessors guessed allocation at a rate not different from chance (52.6%; P = 0.68). One participant experienced mild local bruising that resolved without intervention; no serious adverse events occurred. This protocol provides a reproducible, safety-annotated approach for reflex-based early lower-limb rehabilitation after stroke.

Introduction

Stroke is one of the leading causes of long-term disability worldwide, characterized by sudden neurological deficits and high recurrence rates, and it imposes a substantial burden on patients' quality of life^1,2. Among survivors, hemiplegia is the most common motor impairment, with early-stage flaccid paralysis (Brunnstrom stage I) representing a critical barrier to functional recovery³. Patients at this stage typically present with loss of voluntary motor control, diminished muscle tone, and weakened tendon reflexes, which restrict active task practice and delay rehabilitation gain....

Protocol

This single-center, assessor-blinded randomized controlled trial evaluated whether successive foot needle-pricking could evoke withdrawal-related reflex patterns and accelerate motor recovery in patients with post-stroke flaccid hemiplegia. All procedures involving human participants were conducted in accordance with institutional guidelines and the principles of the Declaration of Helsinki. The study was approved by the Institutional Ethics Committee of Jiangdu People's Hospital (Yangzhou, China) and registered with the Chinese Clinical Trial Registry (ChiCTR2200058142). Written informed consent was obtained from each participant prior to enrollment.

Results

General information
A total of 80 patients were enrolled and randomized 1:1 to the pricking group or the control group. Seventy-six participants completed the outcome assessments and were included in the analyses (pricking n = 38; control n = 38). Baseline characteristics, including age, sex, stroke type, disease duration, and hemiplegic side, were comparable between groups (all P > 0.05; Table 1).

Primary outcomes

Discussion

Stroke is a leading cause of long-term disability and mortality among non-communicable neurological diseases, and its sudden onset and recurrence risk impose substantial burdens on patients' quality of life^22,23. In the flaccid stage of hemiplegia, early restoration of reflex activity and emergence of movement-related output are clinically meaningful targets because voluntary motor control is minimal and opportunities for task practice are limited

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Acupuncture needle, sterile, stainless steel, 0.25 mm × 13 mm (single-use)	AguPunt (CTN)	SKU: A1090	Matches protocol needle specification for superficial plantar needle-pricking
Alcohol prep pad, 70% isopropyl alcohol, individually wrapped	embecta (BD brand)	326895	Skin antisepsis before needling
Biohazard waste bags, autoclavable	Fisherbrand	14-828-244	Regulated medical waste handling for contaminated disposables
Gauze sponges, sterile, 4 in × 4 in, 12-ply	McKesson Brand	16-4242	Local compression/hemostasis after minor bleeding
Nitrile examination gloves, powder-free	Ansell	TouchNTuff 92-600; Mfr. Part No. 92600090	PPE for needling and infection control
Sharps container (puncture-resistant), 1 qt (0.9 L)	BD	305635	Immediate disposal of used needles at point-of-use
Software: G*Power	Heinrich Heine University Düsseldorf (G*Power Team)	v3.1.9.7 (free software)	Sample size/power calculation in manuscript
Software: IBM SPSS Statistics	IBM	v26.0 (licensed software)	Statistical analyses in manuscript