The effectiveness and safety of cupping therapy for stroke survivors: A systematic review and meta-analysis of randomized controlled trials

Article information

J Korean Med. 2021;42(4):75-101
Publication date (electronic) : 2021 December 1
doi : https://doi.org/10.13048/jkm.21039
1Department of Internal Medicine, College of Korean Medicine, Sangji University
2Department of Internal Medicine, College of Korean Medicine, Dongguk University
Correspondence to: Chang-ho Han, Department of Internal Medicine, College of Korean Medicine, Dongguk University, Gyeongju, 38066, Republic of Korea Tel:+82-510-8449, Fax:+82-510-8450
Received 2021 July 16; Revised 2021 August 3; Accepted 2021 November 5.

Abstract

Objectives

ncluding stroke. The aim of this study was to systematically review the clinical evidence of CT for stroke.

Methods

To identify randomized controlled trials (RCTs) reporting the effectiveness and/or safety of CT, seven databases including PubMed, EMBASE, and Cochrane Library were searched for articles published from January 2000 to February 2021 without language restrictions. Meta-analysis was performed using Review Manager 5.4 software and the results were presented as mean difference (MD) or standard mean difference (SMD) for continuous variables and odds ratio (OR) for diverse variables with 95% confidence intervals (CIs). Assessment of the methodological quality of the eligible trials was conducted using the Cochrane Collaboration tool for risk of bias in RCTs.

Results

Twenty-two RCTs with 1653 participants were included in the final analysis. CT provided additional benefit in improving upper limb motor function (Fugl-Meyer assessment for upper limb motor function, MD 6.91, 95% CI 4.64 to 1.67, P<0.00001) and spasticity (response rate, OR 3.28, 95% CI 1.31 to 8.22, P=0.08) in stroke survivors receiving conventional medical treatment. These findings were supported with a moderate level of evidence. CT did not significantly increase the occurrence of adverse events.

Conclusions

This study demonstrated the potential of CT to be beneficial in managing a variety of complications in stroke survivors. However, to compensate for the shortcomings of the existing evidence, rigorously designed large-scale RCTs are warranted in the future.

Introduction

Stroke is one of the leading causes of death worldwide, accounting for 10% of the world’s mortality1). Although stroke mortality is on the decline1), many stroke survivors still suffer from residual disability2). The aging of the population and the reduction in stroke deaths are expected to lead to further increases in the prevalence of stroke and socioeconomic burden in the future3). Therefore, now is the time to pay attention not only to current stroke strategies mainly focused on emergent and intensive care in the acute stage but also to continuous monitoring and medical support for stroke survivors3). Interest in complementary and alternative medicine, represented by traditional or folk medicine, has been increasing as one of the methods to satisfy the unmet needs of stroke survivors4).

Cupping therapy is a form of intervention that provides negative pressure on the skin by suctioning the air inside a cup and has been widely used in multiple cultures throughout the world5,6). In particular, it has one of the most commonly used interventions in modern East Asian traditional medicine to date5). Indications of cupping therapy covered almost all systems of the human body and mind in traditional medicine1), including various complications experienced by stroke survivors6).

In 2010, Lee et al6). published the results of a systematic review of the clinical literature on the effect of cupping therapy for stroke rehabilitation. However, at the time, only two uncontrolled observational studies and three randomized controlled trials (RCTs) comparing the effects of cupping therapy with different unproven techniques were identified in the search, so only a narrative review of the clinical evidence available at the time for this topic was possible.

Therefore, this study aimed to update the findings of the previous study6) by systematically reviewing currently available RCTs, performing a meta-analysis and providing evidence-based information for those considering the application of cupping therapy for stroke patients.

Methods

1. Data sources and search strategy

1) Data sources

Considering that the primary studies included in the previous systematic review on this topic6) have been published since 2000, we searched the following databases from 1 January 2000 to 16 February 2021: English (PubMed, EMBASE, and Cochrane Library), Chinese (China Academic Journals Full-text Database), and Korean databases (Science On, Korean Studies Information Service System, and Oriental Medicine Advanced Searching Integrated System). Twelve major Korean traditional medicine journals were also manually searched for relevant articles.

2) Search strategy

The search terms were used in the form of a combination of (“stroke” OR “cerebral infarction” OR “cerebral hemorrhage” OR “cerebrovascular disorder” OR “cerebrovascular accident” OR “apoplexy” OR “brain ischemia”) AND (“cupping”), but modified to suit the condition of the search platform of each database in Korean, Chinese, and English (Supplement 1). There were no language restrictions. In addition to articles published in academic journals, thesis and conference abstracts were also included. Hand searches were also conducted for related references. This study was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 (Supplement 2 & 3).

2. Study selection and eligibility criteria

1) Study selection

MK and CH screened the retrieved records. The selection of potentially relevant articles for this study was decided after reading the abstract or full text of the articles. The two authors worked independently and any disagreement was resolved by discussion.

2) Types of studies

Parallel-design RCTs that investigated the effectiveness and safety of cupping therapy in stroke patients were selected. Observational studies, qualitative studies, animal studies, and literature reviews were not included. Clinical studies that were nonrandomized studies, crossover-design studies, before-and-after studies, or studies without a control group in comparison to the cupping therapy group were also excluded.

3) Types of participants

Studies that recruited patients who were confirmed to have stroke by clinical signs and symptoms supported by brain imaging were included. There were no other restrictions, such as age, sex, stroke type, or stroke stage. Studies including nonstroke patients were excluded. When more than one study used duplicated data were obviously from the same population, only the one study that provided more information was selected.

4) Types of interventions

We defined cupping therapy as an intervention that provides negative pressure on the skin by suctioning air inside a cup-shaped device (mainly made of plastic, glass, or bamboo).4) Generally, cupping therapy is classified as wet cupping or dry cupping5,6). Wet cupping refers to cupping with bloodletting puncture. In other words, it involves pricking the skin of the cupping site before suction and subsequently drawing blood in addition to cupping. Dry cupping involves only cupping without bleeding. This study included both types of cupping.

5) Types of control interventions

All types of control interventions other than cupping therapy were allowed as control interventions, including active control, sham or placebo control, and no cupping therapy. Therefore, both A versus B and A+B versus B type studies were included.

6) Types of outcome measures

All types of clinical outcomes that evaluated the therapeutic effect and safety of cupping therapy for stroke patients were allowed. Reporting of the response rate based on predefined criteria was also allowed.

Outcomes showing the add-on effect of cupping therapy were also allowed. However, cases that provided only the combined effects of cupping plus other interventions in which the effects of cupping therapy could not be identified were excluded (e.g. cupping + acupuncture, cupping + herbal medicine, and cupping + bloodletting of noncupping sites).

When the outcomes were measured multiple times after the completion of planned treatment, the first measured value was preferentially adopted.

2. Data extraction

One of the authors (MK) extracted data, and another one (CH) cross-checked the data. Disagreements were resolved by discussion between the two reviewers. The extracted data were as follows: number of participants in the final analysis, time-to-onset of stroke, stroke conditions, types and details of intervention, types of control intervention, outcome measures, and findings of each study.

3. Data synthesis

Meta-analysis was conducted when two or more studies provided quantifiable values. In the case of A versus B designs, data were combined when there were two or more studies using the same endpoints and control interventions. In the case of A+B versus B designs, data were combined when there were two or more studies using the same endpoints. Cochrane Collaboration software (Review Manager (RevMan) Version 5.4 for Windows. The Cochrane Collaboration, 2020) was used for data synthesis and constructing forest plots. For continuous variables, the mean difference (MD) and its 95% confidence interval (CI) were calculated using the inverse variance method. However, when the measurement tools were not identical across studies, the standard mean difference (SMD) was calculated. For binomial variables, odds ratios (ORs) and 95% CIs were calculated using the Mantel-Haenszel method. Heterogeneity among trials was evaluated using Higgins’ I2 test7). The fixed effect model was preferentially adopted, but a random effect model was selected when the stroke conditions of the participants were not homogeneous or the statistical heterogeneity between studies was considerable (I2 value ≥ 75%)8). When heterogeneity was substantial, subgroup analysis was considered. Subgroup analysis was also performed based on the type of cupping therapy (dry or wet cupping). When data from 10 or more studies were combined, the possibility of publication bias was assessed using a funnel plot.

4. Risk of bias (RoB) assessment

The Cochrane Collaboration tool for RoB in RCTs (RoB 2) was used to assess the methodological quality of the studies included in the meta-analysis. The RoB 2 consists of five domains: randomization process, deviations from intended interventions, missing outcome data, measurement of the outcome, and selection of the reported results9). Based on the evaluation results for each domain, the overall RoB for each study was judged to be one of the three levels including low, high, or some concerns. The two authors independently evaluated the RoB of individual studies, and any disagreements were resolved through discussion.

5. Level of evidence

The certainty in evidence from the meta-analysis was assessed by the methodology of the grading of recommendations, assessment, development, and evaluation (GRADE)10). Meta-analysis data were imported into GRADEpro, web-based software, and the quality of evidence was rated based on the following criteria: study design, RoB, inconsistency, indirectness, imprecision, and other considerations including publication bias. Synthesizing the ratings of each criterion, the final level of evidence was decided to be high, moderate, low, or very low10).

Results

1. Study selection

A total of 374 articles were identified through the database search, and 3 articles were identified through hand searching, and of these, 50 were excluded due to duplication. The titles and abstracts of the remaining 327 articles were screened, and 271 articles not suitable for this study were excluded. Full texts of the remaining 56 articles were read and 24 articles that did not meet the eligibility criteria of this study were excluded. Out of the remaining 32 articles, 22 articles providing data suitable for quantitative synthesis were finally selected for meta-analysis and methodological quality assessment. The study selection process is summarized in Fig. 1, and a list of articles excluded during the process from full text reading to the final selection is presented in Supplement 4.

Fig. 1

Flowchart of the study selection

1. Characteristics of the included studies

1) Study design and sample size

A total of 22 studies1132) with 1653 participants published in China from 2001 to 2020 were included in the final analysis. Most of them were studies with a 2-arm design with the exception of three studies14,19,31) with 3 arms. The number of participants included in the posttreatment evaluation ranged from 40 to 135 (Table 1).

Characteristics of included studies (Participants, interventions and control interventions)

2) Participants

The participants of all included studies were patients with stroke, and none of the studies limited the stroke subtype of the patients. There was no study that recruited only patients in the acute stage within one week of stroke onset, but most of the participants were patients within 6 months of stroke onset. Of the exceptions, 4 studies included patients with more than 6 months since stroke onset,15,18,30,31) and 3 studies did not provide any information regarding the time from onset (Table 1)22,23,32).

The most commonly treated stroke condition was spasticity, which was reported in 9 studies 1214,16,17,20,23,24,31). Six1214,16,17,24) of these studies targeted patients with upper limb spasticity, of which 412,14,16,17) were about elbow spasticity. There were three studies each on spasticity in lower limbs23), four limbs,31) and nonspecified parts20). The most commonly studied stroke conditions after spasticity were hemiplegic shoulder pain (5 studies)19,22,25,26,28) and poststroke shoulder-hand syndrome (4 studies).21,27,29,30) The remaining studies targeted sensory dysfunction18,32), upper limb dysfunction15), and neglect syndrome (Table 1)11).

Two studies considered the type of syndrome differentiation based on traditional Chinese medicine.15,20) One enrolled patients with spasticity and qi deficiency with blood stasis type15) and the other enrolled patients with upper limb dysfunction with phlegm and blood stasis obstructing collaterals type (Table 1)20).

3) Intervention, control and outcome measures

① A versus B type studies

Two studies17,24) compared the effects of wet cupping and Western medication (baclofen, a muscle relaxant) in patients with upper limb spasticity. In both studies, the treatment period was 4 weeks, the treatment group received wet cupping on the center of the biceps brachii belly twice a week, and the control group was orally administered 10 mg of baclofen three times a day. These two studies evaluated changes in upper limb motor function and spasticity. In terms of the safety of the cupping therapy, one study24) described the plan for adverse event monitoring in the methods session but did not report the results. Another study17) did not provide any information on the safety of cupping therapy (Table 1 & 2).

Characteristics of included studies (Outcome measures and findings)

② A+B versus B type studies

Twenty studies1116,1823,2532) were designed as an A+B versus B form, comparing the add-on effect of cupping therapy with the noncupping control in patients receiving standard treatment for stroke. Three of them14,19,23) were 3-arm studies, and the other 18 were 2-arm studies. No studies used sham devices or placebo controls (Table 1).

Of the 20 studies, 511,19,21,25,31) used dry cupping and 151216,18,20,22,23,2630,32) used wet cupping. The retention time for cupping was between 5 and 15 minutes in both dry and wet cupping studies. The amount of blood drawn by wet cupping therapy ranged from a few drops to 10 ml. Ten13,15,1820,22, 2527,32) of the included studies performed cupping therapy once every other day. The next most common protocols were once a day14,28,30,31) and twice a week12,16,23). The treatment period was most frequently 4 weeks11,12,16,18,21) and ranged between at least 2 weeks and at most 6 months. The most common sites for cupping were the pain site of the affected shoulder for patients with hemiplegic shoulder pain or shoulder-hand syndrome and the center of the biceps brachii belly for patients with upper limb spasticity (Table 1).

The therapeutic effects of cupping therapy for stroke patients was evaluated on various scales. Most of the studies presented the response rates for the main outcomes in stroke survivors. In addition, many other studies measured upper limb motor function using the Fugl-Meyer assessment (FMA) scale, and there were also studies that evaluated overall motor function or sensory function. Some studies assessed the intensity of shoulder pain using a visual analog scale (VAS) or numeric rating scale. There were also studies that assessed the activities of daily living using the Barthel or modified Barthel index. There was only one study15) that assessed neurological deficits using an internationally accepted stroke scale, such as the National Institute Health stroke scale, and no study reported mortality, disability, or recurrence of stroke (Table 1 & 2).

Most studies did not mention safety. One study on dry cupping21) reported that any serious adverse events were observed, and three studies on wet cupping13,15,25) described the adverse events identified during the study period (Table 1 & 2).

2. RoB of the included studies

Only two studies15,24), which provided enough information to confirm that both the random sequence generation and allocation concealment process were properly performed, met the first domain of the RoB 2 (randomization process). The remaining included studies did not provide enough information to judge relevant procedures and were judged to be at the level of raising some concerns in this domain.

In the second domain, deviations from the intended interventions, all studies were judged to be at low RoB. Although patient blinding and performer blinding were not performed, it was judged that this situation was due to the unique nature of the cupping therapy and would not have affected the intended intervention.

In the third domain, missing outcome data, most studies were judged to be at high RoB. This was because they did not mention anything about loss to follow-up or dropout and we could not rule out the possibility that any missingness led to biased results. Only 3 studies15,18,24) reported dropout, and we could confirm that the missingness did not bias the results, these studies were judged to be at low RoB.

In the fourth domain, measurement of the outcome, all the included studies were judged to be at high RoB. This was because no studies mentioned anything about the achievement or impact of assessor blinding.

In the fifth domain, selection of the reported result, we judged that some concerns were raised in the RoB of all included studies. No studies involved previously published study protocol papers prior to initiation of trial. Therefore, we reviewed whether the results session was described in accordance with the plans mentioned in the Methods section of the paper. No significant biases were identified in the Methods and Result sections. However, no studies provided information that could confirm whether the reported outcome was selected from among multiple outcome measurements, and therefore, this issue raised some concerns for all included studies.

The overall RoB of all included studies derived by synthesizing the evaluations in the above domains was judged to be high. The results of the RoB assessment for each domain of the included studies are schematically shown in Supplements 5 and 6.

3. Meta-analysis and evidence level

1) Effectiveness of cupping therapy compared to Western medication

Two studies17,24) compared the effect of wet cupping therapy with Western medication (baclofen 10 mg tid pc [P.O.]) in patients with upper limb spasticity after stroke. The meta-analysis of these two studies showed that cupping therapy was significantly more advantageous in improving upper limb dysfunction assessed by the subdomain score of the FMA scale (MD 5.20, 95% CI 1.51 to 8.88, P=0.006) (Fig. 2). The degree of spasticity assessed by the modified Ashworth scale (MAS) was also significantly improved in the cupping therapy group compared to the Western medication group (MD −0.69, 95% CI −0.82 to −0.56, P<0.00001) (Fig. 3(A)). The proportion of patients who responded positively regarding the clinical aspects of spasticity was also significantly higher in the cupping group (MD 3.81, 95% CI 1.50 to 9.65, P=0.005) (Fig. 3(B)). Changes in the biceps and triceps muscles detected by integrated electromyography were also more favorable with cupping therapy (MD −4.05, 95% CI −6.36 to −1.74, P=0.0006; MD=3.56, 95% CI 1.62 to 5.50, P=0.0003) (Fig. 3(C, D)). The certainty of the evidence assessed by the GRADE approach was low in all cases. This was because of the high RoB and small sample size of the included studies (Supplement 7).

Fig. 2

Forest plot of the effect of cupping therapy versus medication on upper limb motor function Assessed by upper limb motor function subdomain of the Fugl-Meyer assessment scale

Fig. 3

Forest plot of the effect of cupping therapy versus medication on spasticity

2) Effectiveness of cupping therapy as an add-on to conventional treatment

① Activities of daily living (ADL)

Five studies11,13,15,19,26) assessed the additive effect of cupping therapy using the Barthel index (BI) or modified Barthel index (MBI). Combining the data, the additional implementation of cupping therapy for patients who were receiving conventional treatment was significantly more advantageous than the noncupping condition (SMD 1.23, 95% CI 0.21 to 2.25, P=0.02) (Fig. 4), and the level of evidence supporting this result was low (Supplement 8). The subgroup analysis including only wet cupping studies13,15,26) showed similar results (SMD 0.48, 95% CI 0.23 to 0.72, P=0.0002) (Fig. 4). The heterogeneity detected in the whole synthesis (I2=95%) was resolved in the wet cupping subgroup analysis (I2=0%) (Fig. 4). However, when pooling the two studies involving only dry cupping11,19), the significant benefit of cupping therapy disappeared (SMD 2.44, 95% CI −1.10 to 5.99, P=0.18) (Fig. 4), and the level of evidence was also downgraded (Supplement 8).

Fig. 4

Forest plot of the effect of additional cupping therapy on activities of daily living Assessed by Barthel index

② Motor function

i. General motor function

Only wet cupping study18) and one dry cupping study11) evaluated the change in the motor function subdomain score on the FMA scale. Only the dry cupping study showed a significant benefit of cupping therapy (MD 3.50, 95% CI 0.86 to 6.14, P=0.009) (Fig. 5(A)). However, when combining the two studies, the additional benefits of cupping therapy were not confirmed (MD 1.95, 95% CI −2.42 to 6.31, P=0.38) (Fig. 5(A)), and the level of evidence was still very low (Supplement 8).

Fig. 5

Forest plot of the effect of additional cupping therapy on motor function

ii. Upper limb motor function

Seven studies using wet cupping1216,22,26) and one study using dry cupping25) reported changes in the upper limb motor function subdomain score of the FMA scale. All studies showed significantly beneficial effects of additive cupping therapy (Fig. 5(B)). Meta-analysis also showed positive results of cupping therapy (MD 6.91, 95% CI 4.36 to 9.46, P<0.00001) (Fig. 5(B)), which was supported by a moderate level of evidence (Supplement 8). The subgroup analysis including only wet cupping studies showed similar results (MD 7.66, 95% CI 4.64 to 10.67, P=0.01) (Fig. 5(B)) (Supplement 8).

iii. Sensory function

Two studies18,32) compared the response rates with and without additional wet cupping therapy in patients with sensory impairment after stroke. Meta-analysis of these studies showed that the benefit of wet cupping therapy was significant and the level of evidence supporting the result was low (OR 4.35, 95% CI 1.42 to 13.32, P=0.010) (Fig. 6) (Supplement 8).

Fig. 6

Forest plot of the effect of additional cupping therapy on sensory function Assessed by sensory domain of Fugl-Meyer assessment scale

iv. Spasticity

Two studies13,16) assessed the level of spasticity using the MAS before and after wet cupping therapy in patients with upper arm spasticity. The meta-analysis of these two studies showed that the additional effect of wet cupping was significant with a low level of evidence (MD −0.63, 95% CI −0.83 to −0.44, P<0.00001) (Fig. 7(A)) (Supplement 8).

Fig. 7

Forest plot of the effect of additional cupping therapy on spasticity

Seven studies1315,20,23,31) investigated the proportion of participants who responded positively in terms of spasticity after cupping therapy. The meta-analysis of these studies showed the significant benefit of cupping therapy (OR 3.28, 95% CI 1.31 to 8.22, P=0.01) (Fig. 7(B)), and a moderate level of evidence supported this result (Supplement 8). The subgroup analysis of the wet cupping studies showed similar results (OR 3.06, 95% CI 1.13 to 8.26, P=0.03), whereas the dry cupping subgroup did not (OR 9.21, 95% CI 0.43 to 198.49, P=0.16) (Fig. 7(B)) (Supplement 8).

Changes in biceps brachii muscle detected by integrated electromyography in patients with upper limb spasticity were also more favorable for wet cupping (MD −4.45, 95% CI −6.74 to −2.16, P=0.0001) (Fig. 7(C))12,16). However, the level of evidence supporting this benefit was very low (Supplement 8).

v. Shoulder pain

Four studies19,22,26,28) reported changes in shoulder pain measured by a VAS after additive cupping therapy for patients with hemiplegic shoulder pain. The meta-analysis of these studies showed that adjuvant cupping therapy had significant benefits in reducing VAS scores (MD −1.67, 95% CI −1.96 to −1.39, P<0.00001) (Fig. 8(A)), although the level of evidence supporting this effect was very low (Supplement 6). Similar results were reproduced in the subgroup analysis including only the wet cupping studies (MD −1.70, 95% CI −2.05 to −1.35) (Fig. 8(A)) (Supplement 8).

Fig. 8

Forest plot of the effect of additional cupping therapy on shoulder pain

Two studies22,26) investigated the proportion of hemiplegic shoulder pain patients who responded positively to wet cupping therapy. Combining these studies showed that additive wet cupping therapy had significant benefits in improving shoulder pain, although the level of evidence was very low (OR 4.28, 95% CI 1.91 to 9.60, P=0.0004) (Fig. 8(B)) (Supplement 8).

vi. Shoulder-hand syndrome

Four studies21,27,29,30) assessed the response rates to cupping therapy for patients with poststroke shoulder-hand syndrome. The meta-analysis of these studies showed that cupping therapy had significant benefits in increasing the response rate in patients with poststroke shoulder-hand syndrome (OR 2.73, 95% CI 1.35 to 5.53, P=0.005) (Fig. 9). The results of the subgroup analysis of studies involving only wet cupping therapy also reproduced similar results (OR 3.15, 95% CI 1.43 to 6.94, P=0.004) (Fig. 9). However, the level of evidence supporting these findings was very low in all cases (Supplement 8).

Fig. 9

Forest plot of the effect of additional cupping therapy on shoulder-hand syndrome Assessed by response rate

vii. Safety

Five studies13,15,21,24,26) mentioned plans for collecting adverse events (AEs) during the study period. All of them were designed to compare the additional effectiveness of cupping therapy with the noncupping control. One24) of the five studies mentioned the AE collection plan in the Methods section of the article but did not provide any information on the safety profile in the Result section. Out of the 4 studies describing the intervention-related AEs in the Results section, one study21) was about dry cupping, and the others13,15,26) were about wet cupping. The dry cupping study21) reported that they did not identify any serious AEs in either cupping or noncupping groups. One of the wet cupping studies reported the occurrence of blistering with pain after cupping therapy, but did not disclose how many cases were identified26). Therefore, we could secure data available for meta-analysis from only two wet cupping studies13,15).

One study provided wet cupping therapy every other day for 30 days to patients with upper arm spasticity and reported two cases of subcutaneous bleeding at the cupping site13). These AEs spontaneously disappeared after 1 week, and no AEs were identified in the control group13). Another study provided wet cupping therapy every other day for 3 months to patients with upper arm dysfunction and identified two cases of AEs, including either bleeding or pain15). Combining the AEs identified in these two studies, no significant difference was found in the occurrence of AEs between the additional cupping group and the noncupping control group (OR 6.33, 95% CI 0.74 to 53.99, P=0.09) (Fig. 10), and the level of evidence supporting this result was very low (Supplement 8).

Fig. 10

Forest plot of the safety of additional cupping therapy Assessed by incidence of adverse events

Discussion

To confirm the therapeutic effect of cupping therapy, one of the oldest interventions used across the world in multiple cultures5), scientific explorations have been attempted in modern times. Clinical trials have shown the potential of cupping therapy to be effective in a variety of diseases, including herpes zoster, facial palsy, acne, and cervical spondylosis, as well as pain33, 34).

Nevertheless, the mechanism of action of cupping remains unclear35,36). However, the hypotheses that this intervention has local effects, including improving capillary and lymphatic circulation and extension of the underlying tissue, as well as systemic effects through activation of the neuroendocrine immune system resulting from the signaling molecules released from the blood vessels or tissues damaged by the cupping procedure35,36), support the reason why cupping therapy can be applied to a variety of conditions across multiple systems of the whole body.

Among the wide range of indications for cupping therapy, this study mainly presented the effects related to improving various complications in stroke survivors. This topic had already been addressed by a previous systematic review published in 20106). However, at the time, sufficient data for meta-analysis were not obtained, so only narrative reviews of five clinical studies were possible6). Since that previous review6), more RCTs exploring the effect of cupping therapy in patients with stroke have been published. Therefore, we updated the findings of the previous study6) by performing quantitative synthesis and qualitative evaluation of the currently available evidence. To the best of our knowledge, this study is the first to systematically review and meta-analyze RCTs on the effectiveness and safety of cupping therapy in stroke survivors.

The findings of this study showed the potential of cupping therapy as an add-on intervention for stroke survivors receiving conventional treatment. Among the various clinical outcomes, the additional benefits of wet cupping therapy for improving motor function of the upper limb were identified. Cupping therapy may have directly influenced upper limb motor function. However, considering that the original studies supporting this result were derived from patients with upper limb spasticity or hemiplegic shoulder pain and that the main findings of this systematic review also showed the advantage of cupping therapy for improving upper limb spasticity and reducing shoulder pain, we speculate that the effect of wet cupping for improving upper limb motor function may have been the result of muscle tone control and pain relief effects. However, this study could not find evidence supporting the effect of cupping therapy on lower limb motor function.

Another finding of this study, supported by a moderate level of evidence, was that additional wet cupping therapy increased the positive response rate for poststroke spasticity. This effect of wet cupping therapy, although at a very low evidence level, was also confirmed by improvements in MAS scores and decreases in muscle tone of the affected biceps brachii, a flexor muscle that is generally overhypertensive in poststroke elbow spasticity. These findings seem to reflect the possibility that muscle relaxation, one of the known actions of cupping therapy37), could also work on upper limb spasticity in stroke patients.

Other studies have shown the positive potential of adjuvant cupping therapy in a wider range of indications. This study identified additional benefits of cupping therapy for improving ADLs, sensory dysfunction, shoulder pain, and shoulder-hand syndrome in stroke survivors, although the level of supportive evidence was low or very low. The effect of additional cupping to reduce pain and improve functions was confirmed in previous studies targeting patients with pain in various underlying diseases4,5), and this study confirmed that this therapeutic action of cupping therapy could also work in stroke survivors.

This study also identified head-to-head studies comparing the effects of wet cupping therapy with active control interventions. The meta-analysis of these studies showed the possibility of wet cupping therapy being more beneficial than oral administration of baclofen in improving muscle tone and motor function in patients with poststroke upper arm spasticity. However, since there were only two small-sized studies supporting the findings and the level of evidence was low, it is necessary to be careful in interpreting this result.

The findings of this study mainly supported the additional benefits of cupping therapy, especially wet cupping therapy, in upper limb motor function, upper limb spasticity, shoulder pain and shoulder-hand syndrome in stroke survivors. Although the level of evidence was often low or very low, with rare studies with moderate levels of evidence, these findings may be helpful in determining priorities when considering application of cupping therapy for stroke survivors.

Subgroup analysis of wet cupping or dry cupping studies showed that the number of wet cupping studies was higher, and the treatment effect and evidence level were also higher than those of dry cupping studies. The fact that there were more studies on wet cupping than on dry cupping is consistent with the results of previous studies6,33). We found that not only was the number of studies on dry cupping therapy small, but the heterogeneity between those studies was also great. Therefore, it is difficult to draw conclusions about the effectiveness of dry cupping therapy on stroke based on the findings of this study. More clinical evidence needs to be collected.

Further consideration is also required on the effects of wet cupping therapy on stroke survivors, considering that wet cupping is a complex form of at least two kinds of interventions, namely, cupping and bloodletting puncture. In traditional Chinese medicine, bloodletting puncture without cupping is often performed, especially in stroke patients in the acute stage or with impaired consciousness, and a recent clinical trial has recently been published showing that bloodletting puncture could provide clinical benefits to stroke patients with disturbance of consciousness38). Further studies to compare and classify the effects of dry cupping, bloodletting puncture, and their combined form, wet cupping are required.

Generally, cupping therapy has been considered safe33), but AEs including anemia, infection, and scar formation have been reported39,40). There have also been concerns that it might actually cause stroke41). However, this study detected no serious AEs related to cupping therapy and demonstrated that the incidence of AEs in the additional cupping group was not significantly higher than that in the noncupping control group. This is consistent with the suggestions in previous studies that cupping therapy is a relatively safe intervention under the condition that it is carefully performed by experienced practitioners 40). However, considering that the meta-analysis on the occurrence of AEs in this study was based on only two small trials and that most of the reviewed studies did not consider the safety profile of cupping therapy in the process of study design, or omitted the reporting of AEs in the articles, we are hesitant to draw definitive conclusions about the safety of cupping therapy here. In particular, considering that there have been concerns4143) that cupping therapy performed on the neck area might cause arterial dissection by excessively raising the blood pressure of the carotid artery or vertebral artery that supplies cerebral circulation and eventually causes stroke, practitioners need to be careful not to induce excessive stress on the inside of the neck when performing cupping therapy in the neck area for stroke survivors.

This study has several limitations. First, despite our best efforts to secure as many relevant articles as possible, there may have been related trials that were not discovered by the search strategy in this study. We searched some databases based in Korea and China in addition to globally used core databases. This approach may have resulted in not identifying local publications in other regions, such as the Middle East or Africa, where cupping therapy has been used as a traditional intervention.

Second, there was a problem regarding the quantitative limitations of the included studies. Since there was no case in which the meta-analysis included more than 10 original trials, we could not construct a funnel plot to explore the existence of publication bias. Moreover, the scale of individual trials was too small. None of the trials had more than 100 participants per group. Crucially, no studies had previously calculated the optimal sample size for adequate power.

Third, the reporting quality of the included studies was low. Most studies did not clearly disclose how they corrected for the biases related to the random sequence generation, allocation concealment, dropout, and data selection. Most of them also omitted the reporting of AEs, as mentioned above. These omissions in reporting deteriorated the overall quality of the methodology of each trial and consequently lowered the certainty of the evidence derived from this systematic review and meta-analysis.

Fourth, none of the included studies considered blinding. Some researchers have attempted to develop a sham or minimal cupping device as a control intervention for cupping therapy4446). However, no sham/minimal cupping device has been confirmed to be perfectly suitable for blinding patients or practitioners4446). Nevertheless, at least assessor blinding should have been ensured as a minimum measure to reduce detection bias. However, none of the included studies mentioned assessor blinding.

Fifth, the underlying mechanisms of the therapeutic effects of cupping therapy in the context of stroke has not been clearly determined. A previous systematic review6) speculated that the benefit of cupping therapy for stroke rehabilitation may be due to the excretion of excess fluid and toxins and improvements in subcutaneous blood flow. To date, however, all of the hypotheses remain unclear.

Sixth, no conclusion was drawn about the influence of cupping therapy on critical outcomes directly related to stroke itself. In particular, as there are no long-term follow-up outcomes, the effects of cupping therapy on mortality, severe disability, and recurrence of stroke is still unexplored.

Finally, a large number of studies have adopted response rates as the main outcome measure instead of the internationally accepted standardized endpoints. This issue is one of the well-known chronic problems of RCTs dealing with cupping therapy33). It can be a factor that prevents readers worldwide from trusting and adequately understanding the study results.

Conclusion

The findings of this study demonstrated the potential of cupping therapy to be beneficial in managing a variety of complications in stroke survivors. In particular, wet cupping therapy as an add-on for stroke survivors receiving conventional treatment provided significant benefits in improving upper limb motor function and spasticity, and these findings were supported by a moderate level of evidence. It was also found that cupping therapy did not significantly increase the occurrence of AEs, although the level of supporting evidence was very low. However, considering that the overall quality of the methodology of the included studies was low, further large-scale RCTs with rigorous designs are warranted to draw definite conclusions on the effectiveness and safety of cupping therapy for stroke survivors.

Acknowledgments

This study was undertaken as part of the KHIDI, funded by the Ministry of Health & Welfare, Republic of Korea. The funders did not play any role in the design and conduct of this study.

Notes

Conflicts of interest

The authors declare that they have no competing interests.

Author contributions

Conceptualization: CH. Methodology: MK and CH. Formal Analysis: MK and CH. Wiring – Original Draft: MK. Writing – Reviewing & Editing: MK and CH. Supervision: CH. Project Acquisition: CH

Ethical statement

This study did not involve any human or animal experiment.

Funding

This research was supported by a grant from the Korean Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (HB16C00001).

Data availability

The data that support the findings of this study are available from the corresponding author upon reasonable request.

References

1. Naghavi M, Abajobir AA, Abbafati C, Abbas KM, Abd-Allah F, Abera SF, et al. Global regional, and national age-sex specific mortality for 264 causes of death, 1980– 2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet 2017;390(10100):1151–210.
2. Gresham GE, Fitzpatrick TE, Wolf PA, McNamara PM, Kannel WB, Dawber TR. Residual Disability in Survivors of Stroke — The Framingham Study. N Engl J Med 1975;293(19):954–6.
3. Ovbiagele B, Goldstein LB, Higashida RT, Howard VJ, Johnston SC, Khavjou OA, et al. Forecasting the future of stroke in the United States: a policy statement from the American Heart Association and American Stroke Association. Stroke 2013;44(8):2361–75.
4. Shah SH, Engelhardt R, Ovbiagele B. Patterns of complementary and alternative medicine use among United States stroke survivors. J Neurol Sci 2008;271(1):180–5.
5. Al-Bedah AM, Aboushanab TS, Alqaed MS, Qureshi NA, Suhaibani I, Ibrahim G, et al. Classification of cupping therapy: a tool for modernization and standardization. JOCAMR 2016;1(1):1–10.
6. Lee MS, Choi T-Y, Shin B-C, Han C-h, Ernst E. Cupping for stroke rehabilitation: a systematic review. J Neurol Sci 2010;294(1–2):70–3.
7. Higgins JP, Thompson SG. Quantifying heterogeneity in a meta-analysis. Stat Med 2002;21(11):1539–58.
8. Higgins JP, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, et al. Cochrane handbook for systematic reviews of interventions John Wiley & Sons; 2019.
9. Sterne JA, Savović J, Page MJ, Elbers RG, Blencowe NS, Boutron I, et al. RoB 2: a revised tool for assessing risk of bias in randomised trials. BMJ 2019:366.
10. Guyatt GH, Oxman AD, Schünemann HJ, Tugwell P, Knottnerus A. GRADE guidelines: A new series of articles in the Journal of Clinical Epidemiology. J Clin Epidemiol 2011;64(4):380–2.
11. Ji P-b, Wu Z-q, Jia D-p, Wang L, Shu Y-y. Clinical Study of Colored Silica Gel Can Combined with Exercise Therapy for Unilateral Neglect After Stroke. Shanghai J Acu-mox 2020;39(8):983–7.
12. Zhang P, Chen Y, Dai W, Nie L. Observation on the effect of puncturing and cupping combined with rehabilitation training in the treatment of stroke patients with upper limb elbow flexion spasm and analysis of the effect of biceps integrated electromyography. China Rural Health 2020;12(20):75.
13. Li Y. Clinical Study of Blood - letting Puncture and Cupping Combined with Bobath Technique in the Treatment of Upper Limb Spasticity after Stroke. Chinese Journal of Ethnomedicine and Ethnopharmacy 2019;28(21):84–6.
14. Shan Y-l, Liu J-h, Sun L-w, Li Q, Wang J. Therapeutic Observation of Collateral-pricking Cupping for Upper-limb Spasm in Patients with Cerebral Stroke. Shanghai J Acu-mox 2019;38(3):270–4.
15. Jiang L. The Curative Effect of Acupuncture and Cupping Therapy on Upper Limb Dysfunction of Stroke Xinjiang Medical University. [Master’s thesis] 2018.
16. Huang Z, Zhao N, Su Z, Su J, Wu Q. Effects of pricking and cupping combined with rehabilitation training on elbow flexion spasticity of upper limb after stroke and its IEMG value. Chinese Acupuncture & Moxibustion 2018;38(2):119–24.
17. Chen J, Lin S. The clinical effect of pricking and cupping combined with rehabilitation training in the treatment of stroke patients with upper limb elbow flexion spasm. Chinese Journal of Medical Device 2017;30(15):121–2.
18. Chen Y-p. Clinical Research on Hemidysesthesia After Stroke Treated by Acupuncture combined with Collateral-Needling Cupping. Henan Traditional Chinese Medicine 2017;37(1):87–9.
19. Liu H, Liu T, Wang Z. Effect of acupoint injection combined with cupping treatment on the daily life ability of patients with shoulder pain after stroke. Chinese Community Doctors 2016;32(27):169–70.
20. Zhang B. The Clinical Observation of Body Spasm After Stroke Applying The Therapy of Combination Acupucture With Pricking and Cupping. Shandong University of Traditional Chinese Medicine [Master’s thesis] 2016.
21. Cheng X, Cheng C. Cupping combined Conventional Symptomatic Treatment and Rehabilitation Training after Stroke Shoulder-hand Syndrome Randomized Parallel Group Study. Journal of Practical Traditional Chinese Internal Medicine 2014;28(11):27–9.
22. Zhang Q, Wei Z, Cui Y. Bloodletting and cupping combined with exercise therapy to treat 31 cases of stroke and hemiplegia and shoulder pain. Hebei J TCM 2014;36(4):568–9.
23. Miao T. MOTOmed intelligent exercise system combined with blood pricking and cupping for treatment of increased muscle tone of lower limbs in stroke patients. Prac J Med & Pharm 2014;31(3):214–5.
24. Huang Z. Effect of Pricking Blood with Cupping Therapy Combined with Rehabilitation Training on the Spasticity of the Upper Limb in Patients with Stroke. Fujian University of Traditional Chinese Medicine [Master’s thesis] 2014.
25. Yang M. Rehabilitation training combined with cupping to treat 64 cases of shoulder pain after stroke. Forum on Traditional Chinese Medicine 2013;28(6):26–7.
26. Gao L, Chu J, Bao Y. Observation on the effect of blood puncturing and cupping combined with rehabilitation on hemiplegic shoulder pain and upper limb motor function improvement after stroke. Zhejiang Journal of Traditional Chinese Medicine 2012;47(11):821–3.
27. Peng L, Wang Z-t, Li L. Research of Shoulder Hand Syndrome After Stroke Treated by Collateral Disease Theory. Journal of Emergency in Traditional Chinese Medicine 2012;21(3):448–9.
28. Wu Z, Huang W. Observation of puncture and cupping combined with rehabilitation training in the treatment of apoplexy and shoulder pain. Journal of Zhejiang Chinese Medical University 2011;35(3):425.
29. Fu L, Liu W-a, Wu Q-m, Li X-r, Li D-d, Shi X-h, et al. Observations on the Efficacy of Acupuncture Plus Pricking-cupping Bloodletting in Treating Postapoplectic Shoulder-hand Syndrome. Shanghai J Acu-mox 2009;28(3):132–4.
30. Zou C, Zhu G, Bao Y. Treatment of 30 Cases of Shoulder-Hand Syndrome after Apoplexy with Acupuncture and Collateral Puncture Cupping. Zhejiang Journal of Traditional Chinese Medicine 2006;41(6):340.
31. Ding B-y, Cui Y-j. Treatment of Hemiplegia and Joint Contracture after Apoplexy by Acupuncture plus Cupping Therapy: A Report of 52 Cases. Journal of Acupucture and Tuina Science 2003;1(5):38–9.
32. Cui S. Observation on the Curative Effect of Plum-blossom Needle and Cupping in Treating Sequelae. Journal of External Therapy of Traditional Chinese Medicine 2001;10(4):37.
33. Cao H, Li X, Liu J. An updated review of the efficacy of cupping therapy. PLoS One 2012;7(2):e31793-e.
34. Lee MS, Kim JI, Ernst E. Is cupping an effective treatment? An overview of systematic reviews. J Acupunct Meridian Stud 2011;4(1):1–4.
35. Guo Y, Chen B, Wang D-q, Li M-y, Lim CH-m, Guo Y, et al. Cupping regulates local immunomodulation to activate neural-endocrine-immune worknet. Complement Ther Clin Pract 2017;28:1–3.
36. Lowe DT. Cupping therapy: An analysis of the effects of suction on skin and the possible influence on human health. Complement Ther Clin Pract 2017;29:162–8.
37. Bridgett R, Klose P, Duffield R, Mydock S, Lauche R. Effects of Cupping Therapy in Amateur and Professional Athletes: Systematic Review of Randomized Controlled Trials. J Altern Complement Med 2018;24(3):208–19.
38. Yu NN, Xu ZF, Gao Y, Zhou ZL, Zhao X, Zhou D, et al. Wake-Promoting Effect of Bloodletting Puncture at Hand Twelve Jing-Well Points in Acute Stroke Patients: A Multi-center Randomized Controlled Trial. Chin J Integr Med :2020.
39. Wang SZ, Lu YH, Wu M, Chen KJ, Liu Y, Liu LT. Cupping Therapy for Diseases: An Overview of Scientific Evidence from 2009 to 2019. Chin J Integr Med 2021;27(5):394–400.
40. Kim T-H, Kim KH, Choi J-Y, Lee MS. Adverse events related to cupping therapy in studies conducted in Korea: A systematic review. Eur J Integr Med 2014;6(4):434–40.
41. Blunt SB, Lee HP. Can traditional “cupping” treatment cause a stroke? Med Hypotheses 2010;74(5):945–9.
42. Choi JY, Huh CW, Choi CH, Lee JI. Extracranial vertebral artery rupture likely secondary to “cupping therapy” superimposed on spontaneous dissection. Interv Neuroradiol 2016;22(6):728–31.
43. Zuhorn F, Schäbitz WR, Oelschläger C, Klingebiel R, Rogalewski A. Cervical Artery Dissection Caused by Electrical Cupping Therapy with High-Negative Pressure - Case Report. J Stroke Cerebrovasc Dis 2020;29(11):105207.
44. Lauche R, Spitzer J, Schwahn B, Ostermann T, Bernardy K, Cramer H, et al. Efficacy of cupping therapy in patients with the fibromyalgia syndrome-a randomised placebo controlled trial. Sci Rep 2016;6:37316.
45. Lee MS, Kim JI, Kong JC, Lee DH, Shin BC. Developing and validating a sham cupping device. Acupunct Med 2010;28(4):200–4.
46. Teut M, Ullmann A, Ortiz M, Rotter G, Binting S, Cree M, et al. Pulsatile dry cupping in chronic low back pain – a randomized three-armed controlled clinical trial. BMC Complement Altern Med 2018;18(1):115.

Article information Continued

Fig. 1

Flowchart of the study selection

Fig. 2

Forest plot of the effect of cupping therapy versus medication on upper limb motor function Assessed by upper limb motor function subdomain of the Fugl-Meyer assessment scale

Fig. 3

Forest plot of the effect of cupping therapy versus medication on spasticity

Fig. 4

Forest plot of the effect of additional cupping therapy on activities of daily living Assessed by Barthel index

Fig. 5

Forest plot of the effect of additional cupping therapy on motor function

Fig. 6

Forest plot of the effect of additional cupping therapy on sensory function Assessed by sensory domain of Fugl-Meyer assessment scale

Fig. 7

Forest plot of the effect of additional cupping therapy on spasticity

Fig. 8

Forest plot of the effect of additional cupping therapy on shoulder pain

Fig. 9

Forest plot of the effect of additional cupping therapy on shoulder-hand syndrome Assessed by response rate

Fig. 10

Forest plot of the safety of additional cupping therapy Assessed by incidence of adverse events

Table 1

Characteristics of included studies (Participants, interventions and control interventions)

Study ID Participants Interv Con. interv
No TFO Conditions
[11] JiPB2020 30/30 74–106 d neglect syndrome DC+RH
DC: 1–2/d, 5/wk, total 20 times for 4 wks, LI11 LI13 LI10 LI4 ST32 ST34 ST36 ST40 LR3
RH
[12] ZhangP2020 40/40 2–6 mo spasticity, U/E (elb) WC+RH
WC: 10 ml, 2/wk, total 8 times for 4 wks, center of belly of biceps brachii
RH
[13] LiYY2019 48/48 22–135 d spasticity, U/E WC+ST
WC: 5–10 min, 1–2 ml, EOD, total 15 times for 40 min, center of belly of biceps brachii
ST
[14] ShanYL2019 30,30/30 50 d-6 mo spasticity, U/E (elb) WC+EA, WC
WC: 5 min, 2 ml, 5/wk, total 10 times for 2 wks, tense points of affected site
EA
[15] JiangL2018 36/36 1–12 mo U/E dysf + spasticity (SD: psoc) WC+Ac
WC: 10 min, EOD, total 45 times for 3 mns, LI15 LI11 LI10 (affected site)
Ac
[16] HuangZQ2018 30/30 24–165 d spasticity, U/E (elb) WC+ST
WC: 10 ml, 2/wk, total 8 times for 4 wks, center of belly of biceps brachii
ST
[17] ChenJY2017 43/43 1–6 mo spasticity, U/E (elb) WC: 10 ml, 2/wk, total 8 times for 4 wks, center of belly of biceps brachii MED
[18] ChenYP2017 43/43 1 d 7 mo sensory disturbance WC+ST
WC: 8–10 min, 1–2 ml, EOD, total 14 times for 4 wks, PC3 BL40 (affected site)
ST
[19] LiuHY2016 45,45/45 Avr 2.1–2.3 mo HSP DC+AcInj, DC
DC: EOD, total 9 times for 3 wks, SI9 GB21 LI15 Ex-UE13Ashi-point (affected site)
AcInj
[20] ZhangBB2016 30/30 Avr 67–68 d spasticity (SD: qdbs) WC+Ac
WC: 5 min, 1–3 ml, EOD-3/wk, total 9 times for 3 wks, LU5 BL40 BL17 (bilateral)
Ac
[21] ChengXL2014 20/20 NA SHS DC+ST
DC: 10 min, 6/wk, total 24 times for 4 wks, SI9 LI15 TE14 SI11
ST
[22] ZhangQF2014 31/31 NA HSP WC+ST
WC: 10 min, EOD, 30 times for 3 mns, total 30 times for 3 mns, LI15 TE14 LI11 Ashi-point (affected site)
ST
[23] MiaoT2014 30,30/30 Avr 67–68 d spasticity, L/E WC+RH, WC
WC:15 min, 2/wk, total 8 times for 1 mn, most painful points among ST31 ST32 SP10 ST34 GB31 BL56 BL57 SP6
RH
[24] HuangZQ2014 30/30 25–165 d spasticity, U/E WC
WC: 10 ml, 2/wk, total 8 times for 4 wks, center of belly of biceps brachii
MED
[25] YangMY2013 34/30 18–112 d HSP DC+RH
DC: 5–10 min, EOD, total 10 times for 20 days, pain site
RH
[26] GaoLA2015 46/42 < 6 mo HSP WC+RH
WC: 5 min, 5–10 ml, EOD, total 10 times for 20 d
RH
[27] PengL2012 37/37 1–3 mo SHS WC+RH
WC: 10 min, 3–5 drops, EOD, total 10 times for 20 d, pain site
RH
[28] WuZY2011 23/23 18–113 d HSP WC+RH
WC: 5–7 min, ED, total 15 times for 3 wks, pain site
RH
[29] FuL2009 40/40 30–128 d SHS WC+Ac
WC: 2–5 ml, total 30 times for 36 d, LI15 TE14 LI14 LI11 LI10 LI4 EX-UE9 Ahi-point
Ac
[30] ZouC2006 30/30 11–202 d SHS WC+Ac
WC:2 ml, total 20 times for 22 d, Ex-UE & TE14 or SI9 & LI15
Ac
[31] DingBY2003 52/30 3 mo 2 yrs Spasticity, F/E DC+Ac
DC: 15 min, ED, total 36 times for 45 d, Yangming meridian points of flexor muscles of U/E or extensor
Ac
[32] CuiSZ2001 44/38 NA Sensory disturbance WC+EA
WC: 5 min, EOD, total 20 times for 40 d, affected site
EA

Ac, acupuncture; AcInj, acupoint injection; Avr, average; con, control; d, day; DC, dry cupping; dysf, dysfunction; EA, electroacupuncture; elb, elbow; EOD, every other day; F/E, four extremity;HSP, hemiplegic shoulder pain; Interv, intervention; MED, medication; min, minute; mo, month; NA, not available; No, number; psoc, phlegm and blood stasis obstructing collaterals; qdbs, qi-deficiency with blood stasis type; RH, rehabilitation therapy; SD: syndrome differentiation; SHS, shoulder-hand syndrome; ST, standard therapy; TFO, time from onset; U/E, upper extremity; WC, wet cupping; wk, week

Table 2

Characteristics of included studies (Outcome measures and findings)

Study ID Conditions Interv Con Interv Outcome measures Findings
Effectiveness Safety
[11] JiPB2020 neglect syndrome DC+RH RH 1. CBS, 2. MMSE, 3. FMA (motor), 4. MBI, 5. PPCT, 6. CDT, 7. LCT, 8. BLT, 9. Patients satisfaction NA 1. 13.2±2.1 vs 15.6±2.0, 2. 27.5±1.4 vs 25.6±1.9, 3. 45.2±5.5 vs 41.7±4.9, 4. 67.0±13.3 vs 59.0±10.9, 5. 1.00±0.64 vs 1.50±0.75, 6. 1.10±0.541 vs 1.50±0.60, 7. 1.04±0.60 vs 1.44±0.60, 8. 1.20±0.70 vs 1.70±0.80, 9. 82.1±10.0 vs 62.1±9.3
[12] ZhangP2020 spasticity, U/E (elb) WC+RH RH 1. IEMG (biceps), 2. FMA (U/E) NA 1. 33.25±6.84 vs 38.63±7.79, 2. 45.36±12.27 vs 40.46±10.93
[13] LiYY2019 spasticity, U/E WC+ST ST 1. RR (no subjects MAS 0-1), 2. MAS, 3. FMA (U/E), 4. BI AE 1. 25 vs 13, 2. 1.1875±0.76231 vs 1.77083±0.91068, 3. 52.22±11.28 vs 41.97±10.35, 4. 82.87±18.59 vs 74.90±17.53
[14] ShanYL2019 spasticity, U/E (elb) WC+EA, WC EA 1. FMA (U/E), 2. RR, 3. Hmax/Mmax (3-1. Median nerve, 3-2. Ulnar nerve, 3-3. Radial nerve) NA 1. 34.76±16.01 vs 26.00±17.15 vs 17.50±11.22, 2. 30 vs 30 vs 18. 3-1. 0.07±0.10 vs 0.08±0.09 vs 0.13±0.10, 3-2. 0.08±0.05 vs 0.07±0.03 vs 0.12±0.09, 3-3. 0.08±0.10 vs 0.07±0.09 vs 0.14±0.13
[15] JiangL2018 U/E dysf + spasticity (SD: psoc) WC+Ac Ac 1. FMA (U/E), 2. NIHSS, 3. MBI, 4. RR, 5. VAS AE 1. 34.61±7.613 vs 31.36±6.257, 2. 13.06±4.296 vs 16.50±2.104, 3. 67.36±9.296 vs 62.78±7.507, 4. 31 vs 24, 5. no of participants per categories
[16] HuangZQ2018 spasticity, U/E (elb) WC+ST ST 1. MAS, 2. FMA (U/E), 3. IEMG (bicep), 4. IEMG (triceps,), 5. ROM, 6. RR NA 1. 1.57±0.50 vs 2.23±0.43, 2. 46.07±10.28 vs 40.27±10.32, 3. 33.59±6.67 vs 37.08±6.21, 4. 30.30±6.43 vs 27.27±4.53, 5. 48.4±13.3 vs 41.4±10.6, 6. 25 vs 28
[17] ChenJY2017 spasticity, U/E (elb) WC MED 1. RR, 2. MAS, 3. FMA (U/E), 4. IEMG (biceps), 5. IEMG (triceps) NA 1. 39 vs 31, 2. 1.48±0.31 vs 2.21±0.52, 3. 45.2±12.1 vs 40.3±10.8, 4. 33.1±6.7 vs 38.5±7.6, 5. 29.8±6.6 vs 25.7±5.2
[18] ChenYP2017 sensory disturbance WC+ST ST 1. RR, 2. FMA (motor), 3. FMA (sensory) NA 1. 39 vs 32, 2. 68.12 ± 14.79 vs 69.37 ± 13.96, 3. 13.47 ± 2.95 vs 12.09 ± 3.93
[19] LiuHY2016 HSP DC+AcInjDC AcInj 1. VAS, 2. MBI NA 1. 1.96±1.05 vs 3.71±1.39 vs 3.58±1.43, 2. 68.7±5.22 vs 45.6±4.92 vs 46.6±5.06
[20] ZhangBB2016 spasticity (SD: qdbs) WC+Ac Ac 1. RR, 2. CSI NA 1. 29 vs 22
[21] ChengXL2014 SHS DC+ST ST 1. RR, 2. CSI, 3. Brunnstrom stage AE 1. 17 vs 16, 2&3. No of participants per categories
[22] ZhangQF2014 HSP WC+ST ST 1. RR, 2. VAS, 3. FMA (U/E) NA 1. 30 vs 21, 2. 2.58 ± 1.93 vs 4.74 ± 1.53, 3. 43.97 ± 7.29 vs 36.90 ± 8.49
[23] MiaoT2014 spasticity, L/E WC+RH, WC RH RR NA 29 vs 27 vs 28
[24] HuangZQ2014 spasticity, U/E WC MED 1. MAS, 2. FMA (U/E), 3. IEMG (biceps), 4. IEMG (triceps), 5. RR NR 1. 1.53 ± 0.23 vs 2.18 ± 0.44, 2. 45.83 ± 11.77 vs 40.23 ± 10.65, 3. 34.94 ± 6.68 vs 37.12 ± 7.42, 4. 29.73 ± 7.46 vs 26.96 ± 4.13, 5. 27 vs 21
[25] YangMY2013 HSP DC+RH RH 1. NRS, 2. FMA (U/E) NA 1. 2.25±1.40 vs 4.26±1.51, 2. 23.18±3.26 vs 19.20±2.67
[26] GaoLA2015 HSP WC+RH RH 1. RR, 2. VAS, 3. BI, 4. FMA(U/E) AE 1. 41 vs 27, 2. 2.57 ± 1.797 vs 3.60 ± 1.849, 3. 61.20 ± 22.365 vs 50.83 ± 21.411, 4. 36.89 ± 12.946 vs 28.40 ± 14.244
[27] PengL2012 SHS WC+RH RH 1. VAS, 2. RR (hand edema), 3. RR (ROM), 4. RR (FMA, U/E) NA 1. 36 vs 31, 2. 35 vs 34, 3. 34 vs 25, 4. 31 vs 32
[28 WuZY2011 HSP WC+RH RH VAS NA 2.3 ± 0.7 vs 4.1 ± 0.8
[29] FuL2009 SHS WC+Ac Ac 1. VAS, 2.frequency, 3. RR, 4. ROM NA 1. 1.37±1.18 vs 2.54±1.69, 2. 2.73±1.74 vs 4.55±1.21, 3. 37 vs 28, 4-1. Ant flx: 153.6±5.3 vs 102.6±10.8, post ext: 38.8±4.6 vs 21.2±4.1, abd: 145.5±9.7 vs 96.3±11.6, add: 40.1±4.7 vs 27.6±4.6, pron: 42.6±9.5 vs 31.2±6.4, supin: 74.8±11.6 vs 56.6±12.2
[30] ZouCJ2006 SHS WC+Ac Ac RR NA 24 vs 16
[31] DingBY2003 spasticity, F/E DC+Ac Ac RR NA 52 vs 28
[32] CuiSZ2001 sensory disturbance WC+EA EA RR NA 44 vs 34

abd, abduction; Ac, acupuncture; add, adduction; AE, adverse event; Ant, anterie; BLT, bisection line task; CBS, Catherine Bergego scale; CDT, clock drawing test; Con, control; CSI, clinical spasticity index; DC, dry cupping; dysf, dysfunction; elb, elbow; ext, extension; F/E, four extremities; Hmax/Mmax, ratio between the maximum H reflex and the maximum M responses; flx, flexion; FMA, Fugl-Meyer assessment; HSP, hemiplegic shoulder pain; IEMG, integrated electromyography; Interv, intervention; LCT, line cancellation test; MAS, modified Ashworth scale; MBI, modified Barthel indx; MED, medication; MMSE, Mini-Mental status examination; NA, not available; NIHSS, national institute of health stroke scale; post, posterior; PPCT, planar pattern copying test; pron, pronation; psoc, phlegm and blood stasis obsturcting collaterals; qdbs, qi-deficiency with blood stasis; RH, rehabilitation therapy; ROM, range of motion; RR, response rate; SD, syndrome differentiation; SHS, shoulder-hand syndrome; ST, standard therapy; supin, supination; U/E, upper extremity; VAS, visual analogue scale; WC, wet cupping