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. 2021 Apr 9;16(4):e0249313. doi: 10.1371/journal.pone.0249313

Fire Acupuncture versus conventional acupuncture to treat spasticity after stroke: A systematic review and meta-analysis

Xuan Qiu 1,2,*,#, Yicheng Gao 1,2, Zhaoxu Zhang 3, Sijia Cheng 2, Shuangmei Zhang 4,5,#
Editor: Wisit Cheungpasitporn6
PMCID: PMC8034732  PMID: 33836008

Abstract

Background

Post-stroke spasm is currently a complex clinical problem that remains to be resolved. Due to its excellent efficacy and few side effects, clinicians have used fire acupuncture to treat post-stroke spasticity in China.

Objectives

The purpose of this study was to evaluate the clinical efficacy of fire acupuncture compared with conventional acupuncture to treat post-stroke spasms and provide a detailed summary of the commonly used acupoints.

Methods

Eight databases (MEDLINE/PubMed, Web of Science, the Cochrane database, EMBASE, CBM, CNKI, WanFang, and VIP) were searched for randomized controlled trials (RCTs) published from database inception through August 30, 2020. RCTs that compared fire acupuncture with conventional acupuncture as a treatment intervention for patients with spasticity after stroke were included. Revman 5.3 software was used to calculate risk ratios (RR) and standard mean differences (SMD) with 95% confidence intervals (CI). Methodological evaluation or critical appraisal of the included articles was assessed using RoB-2.

Results

Sixteen studies with a total of 1,118 patients were included. Although according to the standards of the Rob 2.0 tool, most studies are considered to have some problems. Comprehensive analysis of the results revealed a consistent trend indicating several advantages of using fire needles compared to conventional acupuncture in treating post-stroke spasms, including the effective rate, recovery rate, and improvement of multiple scales represented by MAS. Concerning secondary outcomes, using the scales of FMA, BI, or NDS in this random model meta-analysis, fire acupuncture exhibited better performance compared to acupuncture [SMD = 2.27, 95%CI [1.40,3.13 (random-effects model) ], [SMD = 1.46,95% CI [1.03,1.90 (random-effects model)], and [SMD = 0.90, 95%CI [0.44,1.35 (random-effects model)], respectively, with moderately high heterogeneity. When the effective rate was used as an outcome in the subgroup analysis, fire needles performed better than conventional acupuncture with respect to damage to the upper or lower limbs, and the thickness and depth of acupuncture. When the modified Ashworth scale (MAS) was used as the outcome, and the damage occurred in the lower extremity, the acupuncture depth exceeded 15mm, or the duration of stroke was longer than six months, the fire needles did not perform better than conventional acupuncture, [SMD = 0.01, 95%CI [-0.47,0.48 (fix-effects model)], [SMD = 0.21 [-0.51,0.93(random-effects model)], and [SMD = 0.76, 95%CI [-0.08,1.60 (random-effects model)], respectively. The acupoints identified with the highest frequencies in this study were Yang-meridian, including LI11-Quchi (nine times), LI4-Hegu (seven times), and ST36-Zusanli (five times). Moreover, no serious adverse effects were reported in any of the studies included in this analysis.

Conclusions

Despite several limitations, this was the first meta-analysis to focus on the treatment of post-stroke spasticity using fire needle acupuncture compared with conventional acupuncture. Our results confirmed that fire needles could provide a better clinical effect than conventional acupuncture, which will help standardize fire needle treatment strategies for post-stroke spasms.

Introduction

Stroke is a major public health problem and ranked as the most common cause of disability [1]. Although recent medical advances have reduced stroke to the fourth cause of death worldwide [2], it still represents a condition that results in devastating physical disability, particularly due to the presence of spasticity [3]. Stroke is the primary cause of death in China [4, 5], and the most common post-stroke complication is spasticity [6]. The prevalence of post-stroke spasticity ranges from 30% to 80% in stroke survivors [7], with a 90% probability of occurrence approximately three weeks after a stroke event [8, 9].

Spasticity is a motor disorder associated with lesions of the central nervous system (CNS) that provoke different clinical syndromes, including spasms, clonus, or hypertonia. It is noteworthy that spasticity is associated with reduced functional independence and a fourfold increase in direct care costs during the first year after stroke [10]. Several therapeutic approaches have been proposed to manage spasticity, including central muscle relaxants (baclofen and baclosan) and peripheral muscle relaxants (xeomi) [1114]. Although medications can relieve the spasms, the relief is not long-lasting, and severe side effects are associated with long-term use of these drugs, including cardiac arrhythmia, hyperkalemia, and amyostasia. These adverse side-effects must be taken into consideration, particularly with elderly patients. Therefore, current studies are focused on identifying alternative treatment strategies, including conventional acupuncture and fire acupuncture. These alternative treatment strategies are prevalent in China and have been incorporated into clinical practice.

Some evidence suggests that acupuncture (including electroacupuncture) could reduce spasticity associated with other CNS diseases [15]. The fire needle is an important component of acupuncture. Due to their excellent curative effect and reduced side effects, fire needles have been used recently by clinicians in China to treat post-stroke spasticity. The efficacy of acupuncture is widely recognized. It has been used to resolve functional recovery problems after CNS injury for many years in Asian countries and is increasingly popular in western countries [15]. However, the general knowledge of fire needles around the world is still insufficient. Additionally, the results of studies on the comparative effectiveness of fire needles and conventional acupuncture in treating spasticity in stroke survivors have been variable. Therefore, it was necessary to conduct a systematic review and meta-analysis of the existing literature to objectively evaluate the clinical efficacy and safety of fire acupuncture for spasms after stroke.

Methods

This systematic review and meta-analysis was registered in the PROSPERO database at http://www.crd.york.ac.uk/PROSPERO(CRD42020188959) and followed the guidelines provided by the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement [16].

The elaboration of the scientific question was based on the PICO strategy [17] considering:

P- Participants/population: Patients diagnosed with limb cramps after stroke will be focused on. No restrictions on gender, age, and ethnicity.

I- intervention(s):Intervention groups are treated with fire needle alone.

C- Comparator(s)/control: The control group used acupuncture instead of fire needle on the basis of any type of acupuncture type

O- Outcome(s): The main outcome indicators included the effective rate (ER), recovery rate (RR), and the modified Ashworth scale (MAS). Secondary outcomes: The secondary outcome indicators included one of the following, Fugl-Meyer (FMA), Barthel Index (BI), and Neurological Function Deficit Scale (NDS).

Data sources and search strategies

Eight databases (MEDLINE/PubMed, Web of Science, the Cochrane database, EMBASE, CBM, CNKI, WanFang, and VIP) were searched for RCTs published from the database inception through August 2020. Various combinations of Medical Subject Headings (MeSH) and non-MeSH terms were used, including “fire needle,” “red-hot needle,” “heated needle,” “needle,” “acupuncture,” “acupotomy,” “stroke,” "cerebrovascular accident,” “spasm,” “paraparesis,” “spastic,” and "spasticity after stroke,” which were searched individually or in combination. Language, study population, or country restrictions were not applied. Moreover, we examined other relevant medical journals and magazines to identify literature not included in the electronic databases. The specific search strategy is provided in the S1 Appendix.

Criteria for inclusion and exclusion

Criteria for inclusion

Studies that met the following conditions were enrolled in the analysis. The studies covered patients diagnosed with stroke and did not take muscle relaxants or have increased muscle tone. The experimental group only used fire acupuncture as the intervention, while the control group was treated with conventional acupuncture or electroacupuncture. The type, thickness, and procedure used for fire acupuncture were not limited. The main outcome indicators included the effective rate, recovery rate, and scales used to assess the degree of spasticity of the extremities. The scales used to assess daily living activities and neurological deficits were used as the secondary outcome indicators. There was no restriction on age, gender, course of the disease, and treatment location. The language of the published research was not limited.

Criteria for exclusion

Studies were excluded based on the following conditions. Fire acupuncture was combined with other treatment methods, including traditional Chinese medicine, blood puncture, rehabilitation, Chinese herbal (patent) medicine, or other treatments in the intervention group. The control group, which was acupuncture or electroacupuncture, was combined with other complex therapies. The patients exhibited increased muscle tone caused by other diseases. Others exclusion criteria that were used included whether the study was retrospective, a review, or a case report, the patient baseline data were inconsistent the study used inappropriate random sequence generation methods, conference papers, or data were missing from the report with no reply from the corresponding author(s).

Data collection, extraction, and management

A piloted data extraction form that has been discussed and developed by all the reviewers was assessed and extracted independently by two authors (QX and ZSM). A standardized form was used to extract data, including general information, study characteristic, participant characteristic, interventions characteristics, outcomes and so on. Any disagreement in data extraction was resolved by discussion or negotiation with a third arbitrator (ZWF). The data included in the study were extracted according to a pre-designed standardized table, including the first author, publication date, and treatment location. The patient information included age, course of the disease, gender, and sample size. The intervention information included selection and depth of acupuncture points, materials used for acupuncture, treatment frequency, adverse events, and whether follow-up examinations occurred. If the data are incomplete or other problems are encountered during data extraction, we contacted the author by phone or e-mail for additional information. Each eligible trial was assigned to a study ID in the following formats: the name of the first author + space + year of publication (e.g, Wang T 2019).

Risk of bias assessment

The Cochrane Handbook for Systematic Reviews(RoB-2) was used to evaluate all studies in this analysis to determine the bias associated with each study. RoB 2 [18] -a revised Cochrane tool assessing risk of bias arising from five domains in randomised trials:(1) the randomisation process, (2)deviations from the intended interventions,(3) missing outcome data, (4) measurement of the outcome, (5) and selection of the reported result. Each domain a risk of bias (low risk, some concerns, or high risk) based on the domain algorithm, and made an overall judgment (low risk, some concerns or high risk) using the described criteria. According to RoB 2, risk-of-bias judgments for each domain have the following categories: low risk of bias, some concerns, or high risk of bias. Judgments are based on and summarise the answers to signalling questions. interior agreement will be assessed for each domain of bias and for the overall RoB judgement by juding Fleiss’s Kappa scores [19, 20]. 44 45 We will group agreement as poor (0.00), slight (0.01–0.20), fair (0.21–0.40), moderate (0.41–0.60), substantial (0.61–0.80) or almost perfect (0.81–1.00) [21].

The STRICTA checklist was used to evaluate the quality of the research. The funnel chart was used to analyze potential publication bias.

Data synthesis

All analyses were conducted with Review Manager V.5.3 software and Stata. If a meta-analysis is not possible, we provided a narrative summary of the results from individual studies. The relative risk (RR) was used to analyze dichotomous outcomes. The mean difference (MD) was used to analyze continuous outcomes with the same unit. Otherwise, the standardized mean difference (SMD) was used. The uncertainty was expressed with 95% confidence intervals (95%CI). We measured heterogeneity using the I2 statistic. Fixed-effects model was used if heterogeneity is found. Random effect model was used where significant statistical heterogeneity exists. Heterogeneity was further explored using meta-regression with backward elimination to analyze the associations between treatment effect and the participant characteristics. Funnel plot was used to examine the potential for publication bias. We judged heterogeneity based on the p-value. When the I2 was less than or equal to 50%, we determined that the heterogeneity was within an acceptable range, and adopted a fixed-effect model for the meta-analysis. We concluded that the heterogeneity was high if the I2 is greater than 50% and used a random-effect model for data analysis. If the number of studies included in the analysis is sufficient, subgroup analysis was used to determine heterogeneity. If the number of included articles exceeds 10, we thought that meta regression can be used to find the source of the heterogeneity.

Outcome measures

Primary outcomes

The main outcome indicators included the effective rate (ER), recovery rate (RR), and the modified Ashworth scale (MAS). The ER and RR reflected the improvement before and after treatment. The MAS is considered to be an important tool to assess spasticity after stroke. The scale is divided into 0, 1, 1+, 2, 3, and 4, to achieve a total of six levels. A higher score indicated increased muscle spasticity (0 = none, 4 = most severe).

Secondary outcomes

The secondary outcome indicators included one of the following, Fugl-Meyer (FMA), Barthel Index (BI), and Neurological Function Deficit Scale (NDS). The FMA covers complex content, including tendon reflexes, muscle coordination, finger grip, joint mobility, and others. The lower the score, the worse the condition (0 = none and 100 = most severe). The BI scale primarily reflected the activities of daily life (0 = not affected and 100 = most severe). The NDS mainly evaluated speech, consciousness, facial paralysis, limb function, and others (0 = none and 45 = most severe). The primary outcome indicators included the effective rate (ER), recovery rate (RR), and the modified Ashworth scale (MAS). The ER and RR reflected the improvement before and after treatment. The MAS scale is divided into 0, 1, 1+, 2, 3, and 4. The higher the score, the worse the degree of muscle spasticity (0 = none, 4 = most severe).

Results

Study selection

A total of 2,354 articles related to the topic were retrieved through a comprehensive database search, of which, 1,097 articles were duplicates. Based on the premise of excluding all irrelevant data, a total of 17 RCTs were included in the analysis. One of the 17 articles was eliminated from the final set of studies because the data were incomplete, and the missing data could not be obtained from the study’s corresponding author. Eventually, 16 articles, with a total of 1,118 patients, were included in the analysis [2237]. The detailed screening process is shown in (Fig 1).

Fig 1. Modified PRISMA flow diagram of included/excluded studies.

Fig 1

Study characteristics

Basic characteristics of the included studies

All trials were conducted in China and published in Chinese, and all studies were carried out based on traditional acupuncture theory. Among the included studies, four were master theses [25, 33, 34, 37]. All the control groups included in the studies received acupuncture treatment. Fifteen of the studies compared fire needles with conventional acupuncture [21, 22, 2527], and one study compared fire needle acupuncture with electroacupuncture [37]. The sixteen studies were published between 2005 and 2018. The ages of the patients ranged from 34 to 80 years. The course of the disease ranged from two months to one year. However, two studies did not report relevant information [23, 30]. Nine articles provided comprehensive information [2124, 27, 31, 33, 34, 36, 37] regarding the type of stroke (intracerebral hemorrhage or cerebral infarction) exhibited by the patients. On the other hand, no specific information concerning the type of stroke was mentioned in four studies [2527, 29, 30]. Three studies described the type of stroke that the patients experienced, but the report lacked detailed figures [28, 32, 35]. Eleven studies emphasized the state of the stroke, of which seven studies recorded that the patients were in the recovery period or sequelae after stroke [23, 25, 28, 3133]. Three studies included patients who were in the recovery period, one study included participants that were in the sequelae period [36] and four studies did not report the related information [23, 25, 28, 3134]. In seven studies, patients received basic medical treatment, including control of blood pressure, regulation of blood glucose, stabilization of blood lipids, and nutritional support [2123, 25, 28, 3132, 34].

In addition to receiving acupuncture, participants in four studies also participated in basic rehabilitation training [22, 24, 28, 30]. All studies described the specific sites of treatment. Five studies assessed the upper limbs [24, 25, 29, 31, 37], one study evaluated the fingers [22], and nine studies assessed the upper and lower limbs [19, 2325, 2729, 33]. Except for three studies that distinguished the severity of stroke [28, 36, 37], none of the other studies provided such a description. Fifteen trials [2235, 37] used ER, and nine studies [24, 25, 27, 28, 30, 3235] used the MAS scale to assess the degree of improvement in spasticity after treatment. The FMA scale also was used in ten studies [2328, 30, 32, 34, 35]. Six studies utilized the BI scale to assess the daily abilities of patients [23, 26, 28, 34, 35, 37]. No studies conducted follow-up assessments. None of the studies reported any fatal adverse events that resulted from acupuncture. The detailed characteristics of each study are shown in (Table 1).

Table 1. Detail of studies include.
First author (year) Age range TG/CG (M±SD) Genger(M:F) TG/CG (M±SD) Sample size (TG/CG) Duraton after Stroke (TG/CG) Control intervention Outcome measures Intergroup differences Follow -up
Peng A [22], 2017 T:57.1±7.8 C:56.7±8.2 T:15/11 C:14/12 26/26 NR AT:30 min,everyday,rest for 1 day after 6 consecutive treatment,30d ER P < 0.05 In favor of FA NR
Yang [23], 2017 T:60.5±5.8 C:61.8 ±6.4 T:11/7 C:12/6 18/18 18.5±3.9/20.5± 4.3(w) AT:10 min,every other day,1 session (1 session = 3 wk, one day rest between each weeks ER;(2)FMA; (3) BI (1)(2)(3)P < 0.05 In favor of FA NR
Sang [24], 2017 T:62.57±5.75 C:63.20±7.07 T:19/11 C:17/13 30/30 168.70±56.99/166.17±87.02(d) EA:30 min,everyday,14d (1)ER;(2);FMA(3)MAS (1)(2)(3)P < 0.05 In favor of FA NR
Liu [25], 2018 NR T:19/12 C:18/13 31/31 15-338/17-342(d) AT:30 min,every other day (1 session = 28d,a total of 14 treatment (1)ER(2)FMA(3)MAS(wrist.elbow) (1)(2)(3)P < 0.05 In favor of FA NR
Chai [26], 2017 T:61.90±3.18 C:58.93 ±11.93 T:17/13 C:16/14 30/30 110.57±36.641/112.70±36.69(d) AT:30 min,everyday,4 weeks (6 times a week) ER (2)FMA (3) BI (1)(2)(3)P < 0.05 In favor of FA NR
Wang [27], 2018 T:64.87±8.18 C:65.67±7.52 T:19/11 C17/13 30/30 99.83±32.31/99.83±32.31(d) AT:30 min,everyday,14d (1)ER; (2)FMA; (3)MAS (wrist,elbow,keen,ankle); (4)NDS(median,ulnar nerve) (1)(2)(3)(4)P < 0.05 In favor of FA NR
Deng [28], 2017 T:61. 4±6. 2 C:63. 2±7. 7 T:25/19 C:22/20 44/42 5.9±2.3/6. 1± 2.6(m) AT:30 min,every other day 2 session (1 session = 7 times) (1)ER; (2)FMA; (3)BI;; (4)MAS; (5)NDS(median, ulnar nerve) (1)(2)(3)(4)P < 0.05 In favor of FA NR
Peng B [29], 2017 T:66.5±1.2 C:67.6±2.3 NC 50/50 NR AT:30 min ER P < 0.05. In favor of FA NR
Sheng [30], 2017 T:55. 62 ± 4.19 C:56.21± 3.98 T:16/15 C:17/14 31/31 185.62±63.19/185.48±64.22 (d) AT:30min,everyday,(1session = 6 times,1 day rest between every session),30d (1)ER;(2)FMA;(3)MAS(wrist, elbow, keen, ankle) (1)(2)(3)P < 0.05 In favor of FA NR
Xu [31], 2015 T:58.3±7.8 C:57.4±8.1 T:29/11 C:27/13 40/40 20.2±4.6/19.6±4.3(w) AT:30 min,every other day 2 session (1 session = 2 weeks) ER P < 0.05. In favor of FA NR
Wang [32], 2015 T:52.3±21.4 C: 5 4.5±20.7 T:22/18 C:20/20 40/40 175.6±94.6/18.72±88.6(d) AT:30 min,every other day(Rest for 1 day after 6 consecutive treatment) (1)ER; (2)FMA; (3)MAS (1)(2)(3)P < 0.05 In favor of FA 1 mo
Yuan [33], 2015 T:64.31±5.62 C:66.25±4.12 T:18/12 C:16/14 30/30 8.22±3.53 /7.71±4.20(m) EA:20min,everyday,2 session(Rest 2 days after 5 consecutive treatment) ER; (2) BI;(3)MAS; (4)NDS (1)(2)(3)(4)P < 0.05.In favor of FA NR
Liu [34], 2014 T:63.97±9.66 C:67.47±9.32 T:16/14 C:13/17 30/30 167.35±34.26/179.33+42.32 (d) AT:30min,everyday,8 times(Rest for 1 day after 6 consecutive treatment) ER; (2)BI; (3)FMA; (4)MA S (1)(2)(3)(4)P 0.05 In favor of FA NR
Zhao [35], 2013 T:61.20±7.35 C:60.70±6.79 T:23/17 C:21/19 40/40 2.76±1.05/3.02±1.41(m) AT:30min,everyday,2 session (1 session = 9 times) (1)ER; (2)FMA; (3)MAS;(4) NDS (1)(2)(3)(4)P < 0.05 In favor of FA NR
Chen [36], 2005 NR T:18/12 C:16/14 30/30 7.8/8(m) AT:30 min,every other day 2m BI P < 0.05. In favor of FA NR
Gao [37], 2004 T:56±0.71 C:54.8±5.13 T:23/7 C:20/10 30/30 250.13/245.6
(d)
AT: everyday (1)ER; (2)NDS (1)(2)P < 0.05 In favor of FA NR

NC = not record; EA = electroacupuncture; AT = acupuncture treatment; ER = effective rate; RR = Recovery rate; FMA = Fugl-Meyer; MAS = The modified Ashworth scale; CSI = Clinic Spastcity Index; BI = Barthel Index; NDS = neurological function deficit scale; TG = treatment group; CG = control group; M = mean; SD = standard deviation.

Details of the intervention groups in the included studies

There were eleven studies [2131] that provided the insertion depth of the fire needles, which ranged from 3mm to 30mm in ten studies. However, one study utilized shallow skin penetration to a depth of only 1mm to 3mm [26]. Concerning the types of fire needles used, they were approximately 0.35mm in diameter with lengths that ranged from 20 to 40 mm. The course of treatment ran between two weeks and one month. It was emphasized that a rest period was to be taken in the middle of the treatment. Additional details are shown in (Table 2). The acupuncture points used with high frequency in the sixteen studies were as follows (Table 3), LI11-Quchi (nine times), LI10-Shousanli (nine times), Extrapoint-baxie (seven times), SJ5-Waiguan (seven times), LI4-Hegu (seven times), SI3-Houxi (six times), ST-Zusanli (five times), LR3-Taichong (four times), SJ4-Yangchi (four times), and SP6-Sanyinjiao (four times). Among all the meridians, the large intestine meridian of the hand-yangming, the small intestine meridian of the taiyang, and the triple energizer meridian of the hand-shaoyang were the three most frequently used. These meridians are usually referred to as the three yang channels of the hand.

Table 2. Details of experimental interventions.
First author (year) points Needle type Depth of Insertion (TG/CG) Treatment Frequency Sessions (TG/CG)
Peng A [22], 2017 SP10(Xuehai), SI3 (Houxi), GB44 (Zuqiaoyin), Extra-point (Baxie), LI10 (Shousanli), LI11 (Quchi), LI14 (Bilao), SJ5 (Waiguan), KI3 (Taixi), SJ4 (Yangchi) NR NR Every two days 30 days (Rest for 2 day after 5 comsec utive treatment)
Yang [23], 2017 Wrist:SJ3 (Zhongzhu), SJ4 (Yangchi), LI4 (Hegu);Upper limb:LI10 (Shousanli), LI11 (Quchi), SJ5(Waiguan);Lower limb:BL40 (Weizhong), BL39 (Weiyang), BL40(Heyang), BL57 (Chengshan), BL37(Yinmen), SP6(Sanyinjiao) 0.35mm*(30~40)mm NR every other day 1 session (1 session = 3 wk)
Sang [24], 2017 LI10 (Shousanli), SJ10(Tianjing) NR 0.5–1 cm (5-10mm) Every day 14 d
Liu [25], 2018 Extra-point (Jiaji)(C3-7、T1-3) 0.35mm*(20~40)mm 0.5–1.5cun (17-33mm) every ther day 1 session 1 session = 28d,a total of 14 treatments)
Chai [26], 2017 LI15(Jianyu), LI11 (Quchi), SJ5(Waiguan), SI3(Yanglao), GB34(Yanglinquan), SP6(Sanyinjiao), ST6(Zusanli),Ashi point 0.5mm*(25~30)mm 1-3mm every day 4 weeks (3 times a week)
Wang [27], 2018 Upper limb:SJ5(Waiguan), LI10 (Shousanli), LI15(Jianyu);Lower limb:ST6
(Zusanli), GB34(Yanglinquan),BL40 (Weizhong), LR3 (Taichong)
0.4mm*40mm 1.5cun (50mm) every day 14 d
Deng [28], 2017 Upper limb:LI15(Jianyu), LI11 (Quchi), LI10 (Shousanli), SJ5(Waiguan), LI4 (Hegu),HT1(Jiquan),LU5(Chize);Lower limb:GB30(Huantiao),ST6(Zusanli), GB34(Yanglinquan),LR3(Taichong),SP6(Sanyinjiao), KI6(Taixi),GB40(Qiuxu)L 0.35mm*40mm 15mm every other day 2 session (1 session = 7 times)
Peng B [29], 2017 LI4 (Hegu),LI11 (Quchi),LI15(Jianyu) NR 3-15mm NR NR
Sheng [30],
2017
LI4 (Hegu),LI11 (Quchi),LI15(Jianyu),LI10 (Shousanli),GB34(Yanglinquan), BL40 (Weizhong), LR3(Taichong),GB30 (Huantiao),HT1(Jiquan) 0.45mm*40mm 3-15mm every two days 30 d (Rest for 2 days after 5 consecut-ive treatment)
Xu [31], 2015 DU20(Baihui),Extra-poin (Taiyang),GB20 (Fengchi), DU16 (Fengfu) HT1(Jiquan),LU5(Chize),PC3(Quze),PC6(Neiguan),PC7(Daling),LI4(Hegu), SI3(Houxi),SP6(Sanyinjiao),SP9(Yinlingquan),(LR3(Taichong),LR2(Jimai),KI10(Yingu),SP5(Shangqiu),GB40(Qiuxu) NR 10-20mm every other day 2 session (1 session = 2 weeks)
Wang [32], 2015 LI15(Jianyu), LI14 (Bilao), LI11 (Quchi),LI10 (Shousanli), SJ5(Waiguan), SJ(Yangchi),SI3(Houxi),LI4(Hegu),Extra-point (Baxie),SP9(Yinlingquan), SP6(Sanyinjiao),KI10(Yingu),LR3(Taichong),GB44(Zuqiaoyin) 0.40mm*45mm 3-15mm every two days 30 d (Rest for 2 days after 5 consecut- tive treatment)
Yuan [33], 2015 A:Upper limb:LI15(Jianyu), LI4(Hegu),HT3(Shaohai),LI3(Sanjian), Lower limb:ST31(Biguan),ST36(Zusanli), LR3(Taichong) B:Upperlimb:SI9(Jianzhen),LU5(Chize),LI10(Shousanli),SI3(Houxi), Lower limb:GB30 (Huantiao),GB31 (Fengshi),BL57(Chengshan),BL60(Kunlun) Group A and Group B alternate 0.30–0.35mm*20-75mm 20-25mm for upper limb; 20-30mm for Lower limb every day 2session(1session = 2 weeks) (Rest for 2 days after 5 consecutive treatm ent)
Liu [34], 2014 A:PC6(Neiguan), LU5(Chize), PC3(Quze), HT3(Shaohai), SI3(Houxi), LI10(Shousanli),LI11 (Quchi) B:PC2(Tianquan),HT2(Qingling),LU3(Tianfu),LI15(Jianyu),LI14(Bilao), SJ13(Naohui) Group A and Group B alternate 0.65mm*50mm 0.3cun (10mm) every two days 8 times
Zhao [35], 2013 Extra-point (Baxie), Extra-point (Shangbaxie), ST36(Zusanli),ST40(Jiexi), ST34(Liangqiui),ST32(Futu),Extra-point (Bafeng) NR NR every three days 2 session (1 session = 3 times)
Chen [36], 2005 Upper limb:LI15(Jianyu),LI10(Shousanli),LI11 (Quchi),LI4 (Hegu),Extra-point (Bafeng);Lower limbs:ST36(Zusanli),ST34(Liangqiui),ST32(Futu),ST40(Jiexi), Extra-point (Baxie) NR NR every other day 2 m
Gao [37], 2004 Jiaji(C4-7),LI15(Jianyu),SJ14(Jianliao), SI13(Quyuan),SI12(Bingfeng), SI11(Tianzong),SJ10(Tianjing),LI5(Yangxi),SJ4(Yangchi),SI3(Houxi), SJ9(Sidu), LI11 (Quchi),LI12(Zhouliao),Extra-point (Waibaxie), NR NR every other day NR
Table 3. Frequency of main acupoints.
Upper limbs Frequency Lower limbs Frequency
Quchi (LI11) 9 Zusanli (ST36) 5
Shousanli (LI10) 9 Taichong (LR3) 4
Baxie (Extra-point) 7 Sanyinjiao (SP6) 4
Waiguan (SJ5) 7 Weizhong (BL40) 3
Hegu (LI4) 7 Taixi (KI3) 3
Houxi (SI3) 6 Yinlinquan (SP9) 3
Yangchi (SJ4) 4 Yanglinquan (GB34) 3
Chize (LU5) 4 Zhaohai(KI6) 2
Bilao (LI14) 3 Qiuxu(GB40) 2

STRICTA checklist for the included studies

The STRICTA checklist is taken from the Standards for Reporting Interventions in Controlled Trials of Acupuncture [38]. Additional details are shown in Table 4. All studies [2237] fully described the style of acupuncture that was used, the rationale for treatment, and the literature sources used to justify the rationale for acupuncture use. Concerning needling details, ten studies [2534] recorded unilateral or bilateral usage of acupuncture points. Only one study [35] did not specify the number of acupuncture points. Five studies [22, 23, 3537] did not describe the depth of acupuncture needle insertion. All eleven studies [2527, 2834, 37] discussed possible reactions that were caused by the use of acupuncture. Due to the particular forms of fire needles that were used, all studies explained the stimulation form of acupuncture. Only one study [22] did not record the needle retention time. Six studies did not introduce the type of acupuncture [22, 23, 29, 30, 3536] two studies [2937] did not describe the number of treatment sessions, and one trial [29] did not mention the treatment frequency. All eleven studies did not combine acupuncture with other therapies. Nine of the studies thoroughly described the setting and context for treatment, and two studies [29, 30] did not. None of the studies described the duration of relevant training for the acupuncture therapists. Also, only three studies [22, 29, 35] mentioned the training time and professional level for acupuncture therapists. All studies provided sources that justified the choice of control subjects.

Table 4. STRICTA, Standards for Reporting Interventions in Controlled Trials of Acupuncture.
Study Acupuncture rationale Needling details Treatment regime Cointerventions Practitioner background Control intervention
First author(year) 1a 1b 1c 2a 2b 2c 2d 2e 2f 2g 3a 3b 4a 4b 5a 5b 5c 6a 6b 6c
Peng A [22], 2017 YES YES YES NO YES NO NO YES NO NO YES YES NO YES NO YES YES YES NO YES
Yang [23], 2017 YES YES YES NO YES NO NO YES YES YES YES YES NO YES NO NO YES NO YES YES
Sang [24], 2017 YES YES YES NO YES YES NO YES YES NO YES YES NO YES NO NO YES NO YES YES
Liu [25], 2018 YES YES YES YES YES YES YES YES YES YES YES YES NO YES NO NO YES NO YES YES
Chai [26], 2017 YES YES YES YES YES YES YES YES YES YES YES YES NO YES NO NO YES NO YES YES
Wang [27], 2018 YES YES YES YES YES YES NO YES YES YES YES YES NO YES NO NO YES NO YES YES
Deng [28], 2017 YES YES YES YES YES YES YES YES YES YES YES YES NO YES NO NO YES NO YES YES
Peng B [29], 2017 YES YES YES YES YES YES YES YES YES NO NO NO NO NO NO YES YES NO NO YES
Sheng [30], 2017 YES YES YES YES YES YES YES YES YES YES YES YES NO NO NO NO YES NO YES YES
Xu [31], 2015 YES YES YES YES YES YES YES YES YES NO YES YES NO YES NO NO YES NO YES YES
Wang [32], 2015 YES YES YES YES YES YES YES YES YES YES YES YES NO YES NO YES YES NO YES YES
Yuan [33], 2015 YES YES YES YES YES YES YES YES YES YES YES YES NO YES NO NO YES NO YES YES
Liu [34], 2014 YES YES YES YES YES YES YES YES YES YES YES YES NO YES NO NO YES NO YES YES
Zhao [35], 2013 YES YES YES NO NO NO NO YES YES NO YES YES NO YES NO NO YES NO NO YES
Chen [36], 2005 YES YES YES NO YES NO YES NO YES NO YES YES NO YES NO NO YES NO NO YES
Gao [37], 2004 YES YES YES NO YES NO NO YES YES YES NO YES NO YES NO NO YES NO NO YES

STRICTA, Standards for Reporting Interventions in Controlled Trials of Acupuncture;1a, style of acupuncture; 1b, rationale for treatment (eg, syndrome patterns, segmental levels, trigger points) and individualisation if used; 1c, literature sources to justify rationale; 2a, points used (unilateral/bilateral); 2b, numbers of needles inserted; 2c, depths of insertion (eg, cun or tissue level); 2d, responses elicited (eg, de qi or twitch response); 2e, needle stimulation (eg, manual or electrical); 2f, needle retention time; 2g, needle type (gauge, length, and manufacturer or material); 3a, number of treatment sessions; 3b, frequency of treatment; 4a, other interventions (eg, moxibustion, cupping, herbs, exercises, lifestyle advice); 4b, setting and context of treatment, including instructions to practitioners, and information and explanations to patients; 5a, duration of relevant training; 5b, length of clinical experience; 5c, expertise in specific condition; 6a, intended effect of control intervention and its appropriateness to research question and, if appropriate, blinding of participants (eg, active comparison, minimally active penetrating or non-penetrating sham, inert); 6b, explanations given to patients of treatment and control interventions, details of control intervention (precise description, as for item 2 above, and other items if different); 6c, sources that justify choice of control; No, no details report; Yes, details reported.

Study quality

According to the criteria of the RoB 2.0 Tool, most of the studies are considered to have some concerns. The items that affect the quality of most studies are the blind implementation and missing outcome data, Only three presented low risk of bias in all the assessed domains [23, 29, 30], other studies have suggested some concerns to a certain degree in each items (Table 5), Fleiss’s Kappa scores in our research Hinted substantia (Fleiss’s Kappa scores = 0.75).

Table 5. Assessment of risk of bias for all included studies using the revised of bias tool (Rob 2.0).
Studies Randomization Intervention Missing Outcome Reported Overall
Data measurement results Risk
Peng A [22], 2017 High Some concerns Some concerns Some concerns Low High
Yang [23], 2017 Low Low Low Low Low Some concerns
Sang [24], 2017 High Low Some concerns Some concerns Low High
Liu [25], 2018 Some concerns Low Low Low Low Some concerns
Chai [26], 2017 Low Low Low Low Low Low
Wang [27], 2018 Low Low Low Low Low Low
Deng [28], 2017 Some concerns Low Low Low Low Some concerns
Peng B [29], 2017 Some concerns Some concerns Low Some concerns Low High
Sheng [30], 2017 Low Low Some concerns Low Low Some concerns
Xu [31], 2015 Some concerns Some concerns Some concerns Low Low Some concerns
Wang [32], 2015 Low Low Some concerns Low Low Low
Yuan [33], 2015 Low Low Low Low Low Low
Liu [34], 2014 Low Low Low Low Low Some concerns
Zhao [35], 2013 Some concerns Low Some concerns Low Low Some concerns
Chen [36], 2005 Some concerns Low Some concerns Low Low Some concerns
Gao [37], 2004 Some concerns Low Some concerns Low Low Some concerns

Low: Low risk of bias

High: High risk of bias

Some concerns: Some concerns of risk of bias

Funnel plot of publication bias. Using a funnel plot, the research team analysed publication bias in all included studies (Fig 2). The outcome suggested that there was little publication bias.

Fig 2. Funnel plot of studies comparing fire acupuncture after stroke in ER.

Fig 2

Results of the meta-analysis

Main outcomes for ER, RR, and MAS

Twelve RCTs in this study used the MAS scale to calculate the effective rates. The meta-analysis revealed that when a fixed model was used, the fire needle group could significantly improve the post-stroke spasticity compared with the acupuncture group [RR = 1.51[1.36,1.66], P<0.001, Fig 3]. Seven studies with a total of 420 patients used the MAS scale to evaluate the recovery rate. The results of the fixed model showed that the therapeutic effect of fire needles was superior [RR = 2.59 [1.75, 3.84], P <0.001, Fig 4]. A total of 12 studies that included 720 patients used the MAS scale to assess changes before and after treatment for patients with spasticity after stroke. The random model results demonstrated that, compared with the acupuncture group, the fire needle group had a stronger correlation with the improved score [MD = 0.47, 95%CI [0.18, 0.77], P = 0.002, Fig 5]. All results are provided in (Table 6).

Fig 3. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stroke in ER.

Fig 3

Fig 4. Meta-analysis of fire acupunture versus acupuncture for spasticity after stroke in RR.

Fig 4

Fig 5. Meta-analysis of fire acupuncture versus acupunture for spasticity after in MAS.

Fig 5

Table 6. Meta-analysis of the effects of fire acupuncture vs. electroacupuncture or acupuncture.
Outcomes or Subgroup 1.1ER Studies 12 Participants 784 Statistical Method Risk Ratio (M-H, Fixed, 95% CI) Effect Estimate 1.51 [1.36,1.66] P Heterogeneity
P<0.00001 P = 0.04;I2 = 46%
1.2ER(for limbs) 8 434 Risk Ratio (M-H, Random, 95% CI) 1.60 [1.29,1.97] P<0.00001 P = 0.004;I2 = 66%
1.2.1ER(for upper limbs) 6 352 Risk Ratio (M-H, Random, 95% CI) 1.71 [1.27,2.30] P = 0.0005 P = 0.001;I2 = 75%
1.2.2ER(for lower limbs) 2 82 Risk Ratio (M-H, Random, 95% CI) 1.37 [1.11,1.70] P = 0.004 P = 0.50;I2 = 0%
1.3ER(for the thickness of FA) 10 566 Risk Ratio (M-H, Fixed, 95% CI) 1.46 [1.30, 1.64] P<0.00001 P = 0.75;I2 = 0%
1.3.1ER(≤0.35mm*(20~40)mm) 4 244 Risk Ratio (M-H, Fixed, 95% CI) 1.42 [1.19, 1.70] P<0.0001 P = 0.79;I2 = 0%
1.3.1ER(>0.35mm*(20~40)mm) 6 322 Risk Ratio (M-H, Fixed, 95% CI) 1.49 [1.28, 1.73] P<0.00001 P = 0.46;I2 = 0%
1.4ER (for the depth of FA) 11 662 Risk Ratio (M-H, Fixed, 95% CI) 1.53 [1.37, 1.71] P<0.00001 P = 0.23;I2 = 22%
1.4.1ER(<3mm) 1 60 Risk Ratio (M-H, Fixed, 95% CI) 1.50 [1.09, 2.06] P = 0.01 Not applicable
1.4.2ER(3-15mm) 7 462 Risk Ratio (M-H, Fixed, 95% CI) 1.57 [1.38, 1.80] P<0.00001 P = 0.05;I2 = 52%
1.4.3ER(>15mm) 3 140 Risk Ratio (M-H, Fixed, 95% CI) 1.39 [1.09, 1,79] P = 0.009 P = 0.61;I2 = 0%
1.5RR(for the whole body) 7 420 Risk Ratio (M-H, Fixed, 95% CI) 2.59 [1.75, 3.84] P<0.00001 P = 0.79;I2 = 0%
1.6MAS(for the whole body) 12 720 Std.Mean Difference (IV, Random, 95% CI) 0.47 [0.18, 0.77] P = 0.002 P<0.0001;I2 = 73%
1.7MAS 8 401 Std. Mean Difference (IV, Fixed, 95% CI) 0.41 [0.21, 0.61] P<0.0001 P = 0.15;I2 = 35%
1.7.1MAS(for upper limbs) 6 332 Std. Mean Difference (IV, Fixed, 95% CI) 0.50 [0.28, 0.72] P<0.00001 P = 0.22;I2 = 29%
1.7.2MAS(for lower limbs) 2 70 Std. Mean Difference (IV, Fixed, 95% CI) 0.01 [-0.47, 0.48] P = 0.98 P = 0.57;I2 = 0%
1.8MAS(the course of disease) 10 500 Std.Mean Difference (IV, Random, 95% CI) 0.50 [0.15, 0.84] P = 0.004 P = 0.0003;I2 = 71%
1.8.1MAS(≤6m) 8 408 Std.Mean Difference (IV, Random, 95% CI) 0.38 [0.05, 0.70] P = 0.02 P = 0.01;I2 = 61%
1.8.2MAS(>6m) 2 92 Std.Mean Difference (IV, Random, 95% CI) 1.14 [-0.49, 2.78] P = 0.17 P = 0.001;I2 = 71%
1.9MAS(the depth of FA) 10 570 Std.Mean Difference (IV, Random, 95% CI) 0.48 [0.11, 0.85 P = 0.01 P<0.00001;I2 = 78%
1.9.1MAS(3-15mm) 8 510 Std.Mean Difference (IV, Random, 95% CI) 0.54 [0.12, 0.95] P = 0.01 P<0.00001;I2 = 81%
1.9.2MAS(>15mm) 2 60 Std.Mean Difference (IV, Random, 95% CI) 0.21 [-0.51, 0.93] P = 0.57 P = 0.16;I2 = 50%
1.10FMA 7 418 Std.Mean Difference (IV, Random, 95% CI) 2.27 [1.40, 3.13] P<0.00001 P<0.00001;I2 = 92%
1.11BI 4 216 Std.Mean Difference (IV, Random, 95% CI) 1.46 [1.03, 1.90] P<0.00001 P = 0.11;I2 = 51%
1.12NDS 3 180 Std.Mean Difference (IV, Random, 95% CI) 0.90 [0.44, 1.35] P = 0.0001 P = 0.11;I2 = 54%

ER = effective rate; RR = Recovery rate; FMA = Fugl-Meyer; MAS = The modified Ashworth scale; CSI = Clinic Spastcity Index;

BI = Barthel Index; NDS = neurological function deficit scale.

Subgroup analysis

Based on the subgroup analysis of stroke-injured limbs on the ER side, the random model results showed that fire needle therapy for the upper and lower limbs produced significant improvements, [RR = 1.71 [1.27, 2.30] and RR = 1.37 [1.11, 1.70], Fig 6], respectively. When using MAS to evaluate the degree of spasm in limbs injured by stroke, the fixed model results revealed that fire needles produced better results than conventional acupuncture in reducing the MAS score for the upper limbs [SMD = 0.50, 95%CI [0.28, 0.72], Fig 7]. However, the lower limbs did not show significant improvement [SMD = 0.01, 95% CI [-0.47, 0.48], Fig 7].

Fig 6. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stoke.

Fig 6

Fig 7. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stoke according to region.

Fig 7

We also conducted a subgroup analysis based on the thickness of the fire needles and acupuncture depth. From the perspective of efficiency, fire needles were better than acupuncture to some extent with low heterogeneity, regardless of the depth or thickness changes in the subgroup analysis. When MAS was used to evaluate the improvement based on acupuncture depth, the random model results demonstrated that the fire needles were significantly deeper compared to conventional acupuncture, where the acupuncture depth was 3 to 15mm [SMD = 0.54, 95% CI [0.12, 0.95], Fig 8]. It is worth noting that when the acupuncture depth exceeded 15mm, the fire needles were not superior to acupuncture [SMD = 0.21, 95% CI [-0.51, 0.93], Fig 8].

Fig 8. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stoke according to depth of acupuncture in MAS.

Fig 8

We also extracted additional information from the studies included in the meta-analysis. When combined with the stroke duration and the extent of improvement as assessed using MAS, the subgroup analysis established that the extent of improvement for the fire needle scale was superior to acupuncture [SMD = 0.38, 95% CI [0.05, 0.70], Fig 9] when the stroke duration was less than six months. As expected, there was no difference between fire needles and conventional acupuncture when the duration of stroke was longer than six months [SMD = 1.14, 95% CI [-0.49, 2.78], Fig 9]. All results are presented in (Table 6).

Fig 9. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stoke according to the course of disease.

Fig 9

Secondary outcomes for FMA, BI, and NDS

A random model meta-analysis was used to assess the secondary outcomes. Using any of the scales, FMA, BI, or NDS, revealed that fire acupuncture exhibited better performances compared to conventional acupuncture [SMD = 2.27, 95% CI [1.40, 3.13], Fig 10], [SMD = 1.46, 95% CI [1.03, 1.90], Fig 11], and [SMD = 0.90, 95% CI [0.44, 1.35], Fig 12], respectively, with moderately high heterogeneity. All results are presented in (Table 6).

Fig 10. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stroke in FMA.

Fig 10

Fig 11. Meta-analysis of fire acupuncture versus acupunture for spasticity after stroke in B1.

Fig 11

Fig 12. Meta-analysis of fire acupuncture versus acupuncture for spasticity after stroke in NDS.

Fig 12

Results of meta-regression

We initially judged that the source of heterogeneity may come from two major aspects. One is the difference related to stroke information, such as the type of stroke (intracerebral hemorrhage or cerebral infarction or both), and the influence of the location of spasm after stroke (Whole body, upper extremity or lower extremity), The second is the difference from the specific implementation process of fire acupuncture, such as the number of acupuncture points, the depth of acupuncture, and the frequency of treatment. All of the above differences may be the source of heterogeneity. Therefore, we performed meta-regression on the following factors. The results suggested that none of the above factors are the cause of heterogeneity (P>0.05), the results showed in (Table 7).

Table 7. Result of meta-regression.

Factor P-value 95% Confidence interval
gauge of needle 0.168 [-0.859424,0.1974747]
Depth of insertion 0.716 [-2.718377,0.3675489]
Treatment Frequency 0.594 [-0.6249931,0.3985297]
Number of needle 0.417 [-0.5323939,1.091061]
Type of stroke 0.206 [-1.0366451,0.2878423]
Location of spasticity 0.784 [-0.5455986,0.6842484]
Pooled -result 0.224 [-1.280113, 4.283351]

Discussion

Joint convulsion, deformities, and muscle atrophy caused by stroke always result in clinical symptoms that include motor dysfunction, joint swelling, pain, and numbness. These symptoms reduce a patient’s quality of life and produce severe physical, psychological, and economic burdens on patients, leading to depression, low self-esteem, despair, and suicidal thoughts [39, 40]. More importantly, stroke survivors may have reduced motivation to pursue rehabilitation training due to spasticity, which, in turn, has negative effects on their recovery outcomes [41, 42]. Multiple studies have recognized the efficacy of acupuncture for stroke sequelae, including relief of anxiety, and improved quality of life, especially for stroke patients [43]. Several meta-analyses focused on clinical practice have demonstrated that acupuncture exerts a beneficial effect in neurological and motor function recovery, including increased balance and muscle strength, and decreased spasticity [44, 45]. Clinical experience has indicated that fire-needle treatment takes less time, requires fewer visits, has more rapid results, and fewer side effects compared to chemical medicinal alternatives [46] At the same time, related clinical research has reported that fire-needle therapy was effective for sequelae of apoplexy [47, 48]. Most of the literature that was included in this study was published after 2015. Thus, the clinical and scientific focus on the use of fire needles has increased in China recently, confirming that fire needles are a reliable and reproducible treatment for post-stroke spasms. Therefore, we conducted this systematic review and meta-analysis of RCTs to summarize the safety and efficacy of fire-needle therapy versus conventional acupuncture used to treat post-stroke spasticity with respect to recovery outcomes.

Comprehensive analysis of our results presented a consistent trend that the use of fire needles was advantageous compared to conventional acupuncture in treating post-stroke spasms. The benefits included improvements in the effective rate, recovery rate, and improvements based on multiple scales represented by MAS. Moreover, there were no reports of serious adverse effects in any of the included studies, such as fainting, dizziness, or unstable blood pressure. This was similar to many clinical studies that have demonstrated the efficacy of conventional acupuncture on multiple sequelae of stroke [43]. In fact, guidelines for adult stroke rehabilitation and recovery recommend acupuncture for the treatment of stroke spastic paralysis. Therefore, we used conventional acupuncture as a control to comprehensively compare the advantages and disadvantages of fire acupuncture and provide valuable clinical evidence to show that fire acupuncture has unique advantages in relieving stroke spasms. Our results confirmed that fire needle treatment for post-stroke spasticity exerted better clinical effects compared to conventional acupuncture, which was consistent with previous clinical experiences and many current research conclusions [46] Also, the degree of improvement in the scores from FMA, BI, and NDS reflected that fire acupuncture decreased spasticity, and improved balance, accuracy, range of motion, and maintained stability in patients who had experienced a stroke.

One important finding was the high degree of heterogeneity among the different types of fire needles that were examined. There was no significant difference in the clinical efficacy of fire needles compared with conventional acupuncture with respect to the thickness of the fire needle diameter. Subgroup analysis revealed that when the fire needle depth exceeded 15mm, the fire needle was more efficient compared to conventional acupuncture [RR = 1.39, 95%CI ([1.09, 1,79), P = 0.009]. However, the improvement in the MAS score is not significant. [SMD = 0.21, 95% CI (-0.51, 0.93), P = 0.57].

The high heterogeneity of some results in the article cannot be ignored. Therefore, we conducted a meta-regression to find the source of heterogeneity. Based on clinical experience, we analyzed the following factors that may cause high heterogeneity, such as the type of stroke, and the location of spasm after stroke, the number of acupuncture points, the depth of acupuncture, and the frequency of treatment. However, the results of meta-regression suggest that none of the above factors is the cause of heterogeneity, but we can not rule out the influence of other uncontrollable factors, such as the period of stroke and the severity of stroke. Unfortunately, due to the fact that there are many missing values for these two factors in the included article, meta-regression cannot be performed, Therefore, we cannot analyze the impact of these two factors on heterogeneity. Future research should be as complete as possible to standardize the clinical application of fire needles and provide evidence for its further promotion.

Stroke is an acute cerebrovascular event, but the sequelae are chronic and persistent. Therefore, we conducted a subgroup analysis of studies that provided data on the course of stroke using MAS as a measurement indicator. Not surprisingly, fire needles exhibited excellent effects when the stroke duration was less than six months. However, when the stroke duration was longer than six months, results from fire needles were not different from conventional acupuncture. This result was consistent with the traditional understanding that a long duration of stroke did not present the best chances for recovery. However, only two studies were included in the subgroup analysis for which the stroke duration that was longer than six months and acupuncture depths that were more than 15mm. Thus, while the clinical implications should not be ignored, the subgroup analysis results should be treated with caution.

Based on traditional Chinese medicine theory, both conventional acupuncture and fire acupuncture act through adjusting the balance of human qi and blood, which, as a whole, produces therapeutic effects that alleviate and cure the diseases. Research has indicated that fire needle stimulation at lesions or acupoints can improve local blood circulation, enhance local tissue metabolism, and even eliminate the pathological changes in local tissues, including edema, hyperemia, exudation, adhesion, calcification, contracture, and ischemia. The results of fMRI studies have indicated that acupuncture therapy in patients with chronic hemiparetic stroke may exhibit modest improvements in upper limb function (specifically, spasticity and range of motion) by increasing ipsilesional motor cortex activity [49, 50]. Previous studies showed that fire needle acupuncture significantly increased BDNF expression, promoted endogenous NSC proliferation and differentiation into neurons, inhibited neuronal apoptosis, reduced inflammation by autophagy, and promoted recovery of motor neuron function [51, 52].

According to the current experimental research results and review, the mechanisms by which fire acupuncture produces antispasmodic effects after stroke are believed to be related to spasm-related neurotransmitters and receptors, and spasticity is relieved by increasing the expression of inhibitory transmitters or decreasing the expression of excitatory neurotransmitters [53]. Acupuncture also has been shown to protect central neurons in multiple ways to achieve functional restructuring of the CNS, which is crucial for strengthening central control of lower motor neurons that regulate muscle tension and to relieve muscle spasticity [54, 55].

Precise descriptions of the protocols used in acupuncture therapy are essential to enable replication and improve the transferability of the results. Generally, an acupuncture treatment plan for spasticity management should include a series of personalized and goal-oriented therapies that are tailored to the specific needs of each patient. As much as possible, we summarized the details of the acupuncture points and intervention details included in each study to provide clinicians with more options for acupuncture. The acupoints that appeared in our investigation with high frequency included the Yang-meridian, such as LI11-Quchi (nine times), LI4-Hegu (seven times), ST36-Zusanli (five times), and others. These results further verified the importance of regulating the Yang-meridian in the treatment of this disease. The result was consistent with the results of a relevant review published in 2017 [45]. Studies have shown that acupuncture in LI4 and LI11 affected local skin temperature and blood flow, while stimulation of LI11 and ST 36 were more likely to activate areas of the brain (frontal lobe, parietal lobe, sub-lobar lobe, cerebellum, and midbrain regions), causing ReHo value changes, which might promote recovery after stroke [5658]. We also compared the key items reported in the included studies with those recommended by the Standards for Reporting Intervention in Clinical Trials of Acupuncture (STRICTA) guideline [38]. It should help clinicians and researchers to examine the standardized and more clearly described details of the studies included in this meta-analysis (Table 3). Interestingly, according to current research, acupuncture is a universally recognized non-drug treatment that can have a beneficial role in diseases that often accompany stroke, including depression, fatigue, and cognitive decline [5961]. These observations also suggest that the efficacy of fire needles in the treatment of post-stroke spasticity may be underestimated.

This is the first meta-analysis to focus on the treatment of post-stroke spasms using fire needle acupuncture compared with conventional acupuncture. Although needle penetration depth and needle thickness are still controversial, our study should help to standardize fire needle treatment strategies for post-stroke spasms. We also expect our results to be adopted by policymakers and promote fire needle acupuncture as an alternative therapy to further reduce the burden of stroke on public health.

Limitation

Several limitations of our study should be noted. First, because of the specifics of the fire needle procedure, it was not possible to carry out blind studies. Thus, the quality of the included trials was not very high. Second, the sample size was not large enough, and the number of events was small (several subgroup analyses included only two studies), which may have influenced the reliability of the conclusions and their interpretation. Third, many factors led to the moderate heterogeneity of particular outcomes in the meta-analysis process, including individual differences, varied treatment protocols (including timing, type, duration, acupoints that were used, and intensity), the stroke type, lesion location, stroke duration, and the spasticity severity. Finally, as shown by the publication dates for the literature included in this study, fire needles, which were primarily used in China, had been widely used only for the past five years in clinical practice to treat post-stroke spasticity. There are very few scholars outside of China who have focused on fire needle treatment for post-stroke spasms, resulting in the majority of participants being Chinese. This result might limit the extrapolation of our conclusions to different populations to some extent. Moreover, dissemination of the results in English would be beneficial in moving this field forward because it would help increase the interests of clinicians and researchers in using and examining the effectiveness of fire acupuncture therapies for spasticity after stroke.

Conclusions

Although the sample size and some methodological qualities of the 16 RCTs included in the present study were not entirely satisfactory, we were able to demonstrate, to a limited extent, the efficacy of fire needle therapy for post-stroke spasticity. Acupuncture has been recommended by the World Health Organization (WHO) as an alternative and complementary strategy for stroke treatment and for improving stroke care. It is anticipated that future higher-quality RCTs will help determine the efficacy and provide reliable support for increased use of fire needles in the treatment of post-stroke spasms.

Supporting information

S1 Checklist. PRISMA.

(DOCX)

S1 Appendix. Search strategy.

(DOCX)

Acknowledgments

We thank Anrong Wang and sijia Cheng for helping to review the full-text articles for eligibility.

The authors would like to express their gratitude to EditSprings (https://www.editsprings.com/) for the expert linguistic services provided.

Data Availability

All relevant data are within the manuscript and its Supporting Information files.

Funding Statement

(1) Zhuweifeng full name:Zhuweifeng Guangdong Provincial Famous Chinese Medicine Studio Construction Project Grant numbers:Guangdong Chinese Medicine Office 2018(5) (2) Zhaoxu Zhang full name:2020 Major Project of Science and Technology Project of Guangdong Province Traditional Chinese Medicine Bureau Grant numbers:(20203015) the funder play an role in the preparation of the manuscript (3) Zhaoxu Zhang full name:Science and technology development plan of Shandong Province Grant numbers:(2017G006021) the funder play an role in the preparation of the manuscript.

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Decision Letter 0

Wisit Cheungpasitporn

22 Jan 2021

PONE-D-20-29966

Fire acupuncture versus conventional acupuncture to treat spasticity after stroke

: A Systematic Review and Meta-analysis

PLOS ONE

Dear Dr. Xuan Qiu,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

==============================

The reviewers have raised a number of points which we believe major modifications are necessary to improve the manuscript, taking into account the reviewers' remarks. Please consider and address each of the comments raised by the reviewers before resubmitting the manuscript. This letter should not be construed as implying acceptance, as a revised version will be subject to re-review.

==============================

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We look forward to receiving your revised manuscript.

Kind regards,

Wisit Cheungpasitporn, MD

Academic Editor

PLOS ONE

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Reviewer #1: Yes

Reviewer #2: Partly

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2. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: No

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Reviewer #1: Yes

Reviewer #2: No

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Reviewer #2: No

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Reviewer #1: PLoS One

December 6th, 2020

Manuscript ID: PONE-D-20-29966

Title: Fire acupuncture versus conventional acupuncture to treat spasticity after stroke: A Systematic Review and Meta-analysis

General comments:

Thank you for the opportunity to review this timely systematic review and meta-analysis on an important and understudied topic on spasticity after stroke. The authors performed a systematic review and meta-analysis following PRISMA checklist aimed to evaluate the clinical efficacy of fire acupuncture compared with conventional acupuncture to treat post-stroke spasms and provide a detailed summary of the commonly used acupoints.

The study is well-written and well-reported according to PRISMA checklist. Also, this study brings some interesting results and new insights as a potential contribution to the field of the Complementary Therapies. I believe that this is a novel paper with a topic that will be great interest for PLoS One readers.

I have some comments, suggestions in order to strengthen the potential contribution of this topic in any revision the author(s) might undertake.

Major Revision:

METHODS

Page 6. First paragraph: after “PRISMA statement” the reference 12” must be enclosed in square brackets [12]

I would like to know how the authors get the guiding question of this systematic review? Was an acronym used, for example PICO, or PICOS, or PICOT? If yes, please provide the structure and description and reference.

Page 6. Please to use MEDLINE/PubMed instead of PubMed as database.

Page 6. Authors need to show more clearly the final key of the search strategy in each of the 8 databases accessed, mainly respecting the combinations of controlled descriptors (eg: MeSh Terms (MEDLINE / PubMed), emtree terms (EMBASE) ; etc ...) and intersections with keywords and synonyms using the Boolean AND & OR operators. I recommend that the authors present the search strategy in each database in the form of a table, containing the date on which the search was processed.

Page 7. Data collection, extraction, and management.

Make it clear in the text when data were collected in the databases.

Another important point is to report how data was extracted (what information was extracted?)

I have checked the protocol registered in the PROSPERO CRD42020188959 and it is well described there. I suggest keeping the text in that part of the article: “A piloted data extraction form that has been discussed and developed by all the reviewers will be assessed and extracted independently by two authors (ZSM and QX). A standardized form will be used to extract data, including general information, study characteristic, participant characteristic, interventions characteristics , outcomes and so on. Any disagreement in data extraction will be resolved by discussion or negotiation with a third arbitrator (ZWF). Contact the author for more information if necessary. Each eligible trial will be assigned to a study ID in the following formats: the name of the first author + space + year of publication (e.g, Wang T 2019).”

Page 7. Risk of bias assessment.

Please replace the Cochrane Bias Risk Assessment (RoB-1) to the recently updated and updated Cochrane Tool (RoB-2), since RoB-1 is coming into disuse.The internal validity and risk of bias of trials should be assesd using RoB 2 - a revised Cochrane tool assessing risk of bias arising from five domains in randomised trials: the randomisation process, deviations from the intended interventions, missing outcome data, measurement of the outcome, and selection of the reported result. Each domain a risk of bias (low risk, some concerns, or high risk) based on the domain algorithm, and made an overall judgment (low risk, some concerns or high risk) using the described criteria (Sterne et al., 2019).According to RoB 2, risk-of-bias judgments for each domain have the following categories: low risk of bias, some concerns, or high risk of bias. Judgments are based on and summarise the answers to signalling questions. RoB 2 also includes algorithms that map responses to signalling questions to a proposed risk-of-bias judgment for each domain. Response options for an overall judgment are the same as those for individual domains. The study can be judged to have (1) a low risk of bias for all domains for this result (low risk of bias), (2) raise some concerns in at least one domain for this result but not to be at high risk of bias for any domain (some concerns), or (3) have a high risk of bias in at least one domain for this result or have some concerns for multiple domains in a manner that substantially reduces confidence in the result (high risk of bias). Overall risk of bias also generally corresponds to the worst risk of bias in any of the domains. However, if a study is judged to have some concerns about risk of bias for multiple domains, it might be judged as having a high risk of bias overall. (Sterne et al., 2019).

Sterne JAC, Savović J, Page MJ, et al. RoB 2: a revised tool for assessing risk of bias in randomised trials. BMJ 2019;366:l4898. doi:10.1136/bmj.l4898.

RESULTS

Table 1. Detail of studies include

Please, put the meaning of the second column (T / C) in the figure caption: (Treatment / Control group).

Still in the second column "Age range" replaced to "Age range (M ± SD)" and put the meaning in the legend - mean and standard deviation.

Check the studies Liu et al., 2018 and Chen et al., 2005, as there is no standard deviation. It is necessary to be consistent and maintain standardization.

The study by Sheng et al 2017 the control group should be average age 56.21 instead og 5 6.21 (remove the space)

The study by Wang et al., 2018 the average age of the control group is misspelled. In the results on page 9 it is stated that ”The ages of the patients ranged from 34 to 80 years. Therefore, I believe that instead of C: 99.13 ± 33.86 it must be wrong. Please check.

DISCUSSION

Page 17. Please, consider to include the reference doi:10.1177/2515690X19834169, together with the others [53,55].

“Interestingly, according to current research, acupuncture is a universally recognized non-drug treatment that can have a beneficial role in diseases that often accompany stroke, including depression, fatigue, and cognitive decline[53-55; Abrahão et al., 2019 ].”

Reviewer #2: 1. Search terms need to provided in complete. "as an example is provided in the Supplementary material" is not acceptable. Search terms in Eight databases are different (PubMed, Web of Science, the Cochrane database, EMBASE, CBM, CNKI, WanFang, and VIP) Please attach syntax used in each database as supplementary.

2. Who are “two independent investigators”?

3. It will be better to show kappa for the selection and data extraction. Please show the data of kappa of agreement during the systematic searches. How disagreements were solved during the systematic search among two independent reviewers?

4. Please make the data for this review publicly available, possibly through the Open Science Framework (osf.io). Items to include: list of excluded studies, commands for statistical analysis, spreadsheets or data used for the meta-analyses, etc. Making data publicly available will promote the reproducibility of the review and is best practices for systematic reviews and meta-analyses.

5. Figure1, suggest to use PRISMA 2009 Flow Diagram platform

6. Forrest plots and funnel plots need to be provided.

7. Random or Fixed effect was used, needs to be specified in the abstract.

8. Authors should discuss the reason of heterogeneity.

9. There is still a considerable heterogeneity as in your limitation. Meta-regression analysis is then strongly recommended.

10. -The PICOS of the meta-analysis should be clearly reported.

**********

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Reviewer #1: Yes: Luís Carlos Lopes-Júnior

Reviewer #2: No

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Decision Letter 1

Wisit Cheungpasitporn

2 Mar 2021

PONE-D-20-29966R1

Fire acupuncture versus conventional acupuncture to treat spasticity after stroke

: A Systematic Review and Meta-analysis

PLOS ONE

Dear Dr. Xuan Qiu,

Thank you for submitting your manuscript to PLOS ONE. After careful consideration, we feel that it has merit but does not fully meet PLOS ONE’s publication criteria as it currently stands. Therefore, we invite you to submit a revised version of the manuscript that addresses the points raised during the review process.

==============================

ACADEMIC EDITOR: Our expert reviewer(s) have recommended some minor revisions to your manuscript. Therefore, I invite you to respond to the reviewer(s)' comments as below and revise your manuscript.

==============================

Please submit your revised manuscript by Apr 16 2021 11:59PM. If you will need more time than this to complete your revisions, please reply to this message or contact the journal office at plosone@plos.org. When you're ready to submit your revision, log on to https://www.editorialmanager.com/pone/ and select the 'Submissions Needing Revision' folder to locate your manuscript file.

Please include the following items when submitting your revised manuscript:

  • A rebuttal letter that responds to each point raised by the academic editor and reviewer(s). You should upload this letter as a separate file labeled 'Response to Reviewers'.

  • A marked-up copy of your manuscript that highlights changes made to the original version. You should upload this as a separate file labeled 'Revised Manuscript with Track Changes'.

  • An unmarked version of your revised paper without tracked changes. You should upload this as a separate file labeled 'Manuscript'.

If you would like to make changes to your financial disclosure, please include your updated statement in your cover letter. Guidelines for resubmitting your figure files are available below the reviewer comments at the end of this letter.

If applicable, we recommend that you deposit your laboratory protocols in protocols.io to enhance the reproducibility of your results. Protocols.io assigns your protocol its own identifier (DOI) so that it can be cited independently in the future. For instructions see: http://journals.plos.org/plosone/s/submission-guidelines#loc-laboratory-protocols

We look forward to receiving your revised manuscript.

Kind regards,

Wisit Cheungpasitporn, MD

Academic Editor

PLOS ONE

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Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: No

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: PLoS One

February 13th, 2021

Manuscript ID: PONE-D-20-29966

Title: Fire acupuncture versus conventional acupuncture to treat spasticity after stroke: A Systematic Review and Meta-analysis

General comments:

Thank you for the opportunity to review again this timely systematic review and meta-analysis on this relevant topic

The authors have responded appropriately to all my suggestions and recommendations. The article is better presented in this version.

Just a few minor adjustments need to be made:

Minor Revision:

Abstract: Add in the “method” that the methodological evaluation or critical appraisal of the included articles was assessed using RoB-2. And in the results, to add that “according to the criteria of the RoB 2.0 tool, most of the studies are considered to have some concerns.

METHODS

Data collection, extraction, and management: write the phrase in the past instead of using the verb in the future.

Data syntheses: Same. Please use the past tense “Random effect model were used….”

RESULTS

Table 5. Please to replace the symbols “+/-” by the official of RoB-2

Low (+)

High (-)

Some concerns (?)

Also the column “Overal risk” shoud be presenting as the last column in this Table.

Ad hoc consultant.

Reviewer #2: Authors welcomed all suggestions and observations comprised in the first revision of the paper.

Authors have satisfied the comments of the reviewers

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Prof. Dr. Luís Carlos Lopes Júnior

Reviewer #2: No

[NOTE: If reviewer comments were submitted as an attachment file, they will be attached to this email and accessible via the submission site. Please log into your account, locate the manuscript record, and check for the action link "View Attachments". If this link does not appear, there are no attachment files.]

While revising your submission, please upload your figure files to the Preflight Analysis and Conversion Engine (PACE) digital diagnostic tool, https://pacev2.apexcovantage.com/. PACE helps ensure that figures meet PLOS requirements. To use PACE, you must first register as a user. Registration is free. Then, login and navigate to the UPLOAD tab, where you will find detailed instructions on how to use the tool. If you encounter any issues or have any questions when using PACE, please email PLOS at figures@plos.org. Please note that Supporting Information files do not need this step.

Decision Letter 2

Wisit Cheungpasitporn

16 Mar 2021

Fire acupuncture versus conventional acupuncture to treat spasticity after stroke

: A Systematic Review and Meta-analysis

PONE-D-20-29966R2

Dear Dr. qiu,

We’re pleased to inform you that your manuscript has been judged scientifically suitable for publication and will be formally accepted for publication once it meets all outstanding technical requirements.

Within one week, you’ll receive an e-mail detailing the required amendments. When these have been addressed, you’ll receive a formal acceptance letter and your manuscript will be scheduled for publication.

An invoice for payment will follow shortly after the formal acceptance. To ensure an efficient process, please log into Editorial Manager at http://www.editorialmanager.com/pone/, click the 'Update My Information' link at the top of the page, and double check that your user information is up-to-date. If you have any billing related questions, please contact our Author Billing department directly at authorbilling@plos.org.

If your institution or institutions have a press office, please notify them about your upcoming paper to help maximize its impact. If they’ll be preparing press materials, please inform our press team as soon as possible -- no later than 48 hours after receiving the formal acceptance. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information, please contact onepress@plos.org.

Kind regards,

Wisit Cheungpasitporn, MD

Academic Editor

PLOS ONE

Additional Editor Comments:

I reviewed the revised manuscript and the response to reviewers' comments. Revised Manuscript is well written. All comments have been addressed and thus accepted for publication.

Reviewers' comments:

Reviewer's Responses to Questions

Comments to the Author

1. If the authors have adequately addressed your comments raised in a previous round of review and you feel that this manuscript is now acceptable for publication, you may indicate that here to bypass the “Comments to the Author” section, enter your conflict of interest statement in the “Confidential to Editor” section, and submit your "Accept" recommendation.

Reviewer #1: All comments have been addressed

Reviewer #2: All comments have been addressed

**********

2. Is the manuscript technically sound, and do the data support the conclusions?

The manuscript must describe a technically sound piece of scientific research with data that supports the conclusions. Experiments must have been conducted rigorously, with appropriate controls, replication, and sample sizes. The conclusions must be drawn appropriately based on the data presented.

Reviewer #1: Yes

Reviewer #2: Yes

**********

3. Has the statistical analysis been performed appropriately and rigorously?

Reviewer #1: Yes

Reviewer #2: Yes

**********

4. Have the authors made all data underlying the findings in their manuscript fully available?

The PLOS Data policy requires authors to make all data underlying the findings described in their manuscript fully available without restriction, with rare exception (please refer to the Data Availability Statement in the manuscript PDF file). The data should be provided as part of the manuscript or its supporting information, or deposited to a public repository. For example, in addition to summary statistics, the data points behind means, medians and variance measures should be available. If there are restrictions on publicly sharing data—e.g. participant privacy or use of data from a third party—those must be specified.

Reviewer #1: Yes

Reviewer #2: Yes

**********

5. Is the manuscript presented in an intelligible fashion and written in standard English?

PLOS ONE does not copyedit accepted manuscripts, so the language in submitted articles must be clear, correct, and unambiguous. Any typographical or grammatical errors should be corrected at revision, so please note any specific errors here.

Reviewer #1: Yes

Reviewer #2: Yes

**********

6. Review Comments to the Author

Please use the space provided to explain your answers to the questions above. You may also include additional comments for the author, including concerns about dual publication, research ethics, or publication ethics. (Please upload your review as an attachment if it exceeds 20,000 characters)

Reviewer #1: The authors have responded appropriately to all my questions and recommendations.

The manuscript is better presentable right now and, therefore, I approve this version for publication at PLOS ONE.

Dr. Luís Carlos Lopes Júnior

Reviewer #2: Authors welcomed all suggestions and observations comprised in the first revision of the paper.

No further change is necessary in the opinion of the reviewer.

Authors have satisfied the comments of the reviewers

**********

7. PLOS authors have the option to publish the peer review history of their article (what does this mean?). If published, this will include your full peer review and any attached files.

If you choose “no”, your identity will remain anonymous but your review may still be made public.

Do you want your identity to be public for this peer review? For information about this choice, including consent withdrawal, please see our Privacy Policy.

Reviewer #1: Yes: Prof. Dr. Luís Carlos Lopes-Júnior

Reviewer #2: No

Acceptance letter

Wisit Cheungpasitporn

22 Mar 2021

PONE-D-20-29966R2

Fire Acupuncture versus Conventional Acupuncture to Treat Spasticity after Stroke: A Systematic Review and Meta-analysis

Dear Dr. Qiu:

I'm pleased to inform you that your manuscript has been deemed suitable for publication in PLOS ONE. Congratulations! Your manuscript is now with our production department.

If your institution or institutions have a press office, please let them know about your upcoming paper now to help maximize its impact. If they'll be preparing press materials, please inform our press team within the next 48 hours. Your manuscript will remain under strict press embargo until 2 pm Eastern Time on the date of publication. For more information please contact onepress@plos.org.

If we can help with anything else, please email us at plosone@plos.org.

Thank you for submitting your work to PLOS ONE and supporting open access.

Kind regards,

PLOS ONE Editorial Office Staff

on behalf of

Dr. Wisit Cheungpasitporn

Academic Editor

PLOS ONE

Associated Data

    This section collects any data citations, data availability statements, or supplementary materials included in this article.

    Supplementary Materials

    S1 Checklist. PRISMA.

    (DOCX)

    S1 Appendix. Search strategy.

    (DOCX)

    Attachment

    Submitted filename: Response to Reviewers.docx

    Attachment

    Submitted filename: Response to Reviewers.docx

    Data Availability Statement

    All relevant data are within the manuscript and its Supporting Information files.


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