Extracorporeal shock wave therapy and how to treat frozen shoulder

 

 

 

Extracorporeal Shockwave Therapy As an Adjunctive Therapy for Frozen Shoulder

 

A Systematic Review and Meta-analysis

 

 

Ruihan Zhang,* MMed, Zhenyu Wang,*† MD, Ruishu Liu‡ MMed, Nan Zhang,* MMed, Jiaxun Guo,* MMed, and Yunxia Huang,* MMed

Investigation performed at Yongchuan Hospital, Chongqing Medical University, Chongqing, China

 

 

Background: The best nonsurgical treatment for frozen shoulder is still unclear. Extracorporeal shockwave therapy (ESWT) is an innovative adjunctive treatment for frozen shoulder, but its effect is still unclear.

Purpose: To evaluate the published literature regarding the potential of ESWT as an adjunctive therapy for frozen shoulder.

Study Design: Systematic review; Level of evidence, 1.

Methods: Searches were conducted in the PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure (CNKI), and VIP Information databases for relevant studies between inception and November 2020. Included were randomized controlled trials (RCTs) for frozen shoulder that compared ESWT with routine treatments to controls. There were no restrictions on the treatment period, type of ESWT, or severity of symptoms. At least 1 of the following outcome indices was assessed: visual analog scale (VAS) for pain, Constant-Murley score (CMS) for shoulder function assessment, or external rotation range of movement (ER ROM).  RevMan 5.3 software was used to evaluate the bias and quality of the included studies. For continuous variables, the mean difference (MD) or standardized MD (SMD) with the 95% CI was extracted. For dichotomous data, event ratios and sample sizes were extracted.

Results: Overall, 20 studies were included. The ESWT used as an adjunct to other interventions had better outcomes compared with control groups regarding immediate and short-term analgesic effects (immediate: MD, –1.10 [95% CI, –1.27 to –0.92], P < .00001; short-term: MD, –0.72 [95% CI, –0.94 to –0.50], P < .00001) as well as immediate function (SMD, 1.54 [95% CI, 1.19 to

1.89], P < .00001], I2 ¼ 0%).  There was significant heterogeneity between studies for long-term analgesia (MD, –0.90 [95% CI,

–1.40 to –0.41], P < .00001, I2 ¼ 89%) and ER ROM (MD, 10.31 [95% CI, 3.46 to 17.17], P < .003, I2 ¼ 93%).

Conclusion: ESWT seems to be beneficial to patients with frozen shoulder by alleviating pain and improving function. ESWT could be used as an adjunct therapy to routine treatments, although the quality of the included RCTs was hampered by significant heterogeneity regarding long-term analgesia and joint ROM.

Keywords: extracorporeal shockwave therapy; frozen shoulder; pain; motor function; meta-analysis

 

 

 

Frozen shoulder is a common musculoskeletal disorder characterized by pain, limited joint mobility, and dysfunction,18 with prevalence rates ranging from  <1% to  2%.19

Frozen shoulder is clinically divided into 3 overlapping phases. The painful freezing phase has a duration of 10 to

36 weeks and is characterized by pain and stiffness around the shoulder, which may worsen at night. The adhesive phase is characterized by restricted range of movement (ROM) with a gradual relief of pain, which occurs at 4 to

12 months.  The   resolution phase with   spontaneous improvement in the ROM takes 12 to 42 months.7 Frozen shoulder is a self-limited condition, but the recovery may be

 

 

The Orthopedic Journal of Sports Medicine, 10(2), 23259671211062222

DOI: 10.1177/23259671211062222 The Author(s) 2022

 

Slow and incomplete, which reduces patients’ activities of daily living and increases their medical burden.18, 26

Because of the uncertainty of the  efficacy  and  risk of surgical treatment,  nonsurgical treatments  are  more likely   chosen  by  patients.2,17   Among   them,  intraarticular steroid injection and  physical therapy are  commonly  used  nonsurgical treatments and  have shown some benefits.27,40  However, because the 3  stages of frozen shoulder often   overlap and   the  clinical symptoms of patients are  complex, adjuvant  therapy  is  often  needed throughout the  course of treatment.  Zhang et al 40  and Dias  et al 7 identified that the  benefits of steroid injection were specific  to the  painful freezing phase and  not  to the adhesive phase of frozen shoulder. Physical therapy provides more obvious benefits in the adhesive phase than in the painful freezing phase.40

 

 

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In  recent  years, extracorporeal shockwave therapy (ESWT)  has  been  increasingly used  as an  adjunct to other interventions in some  randomized controlled trials (RCTs) and   has   shown satisfactory  improvement in  multiple aspects.3,13,30  To  date, there is  no  specialized meta- analysis or systematic review evaluating the  effectiveness of ESWT as an adjunctive therapy in treating frozen shoulder.  Therefore, the purpose of this study was to perform a

Meta-analysis to evaluate the effectiveness of ESWT as adjunctive therapy for frozen shoulder. We hypothesized that ESWT would be a positive adjunctive therapy in the treatment of frozen shoulder.

 

 

METHODS Search Strategy

A comprehensive search utilizing Preferred Reporting Items for  Systematic Reviews and  Meta-Analyses guide- lines was  performed via  PubMed, EMBASE, Cochrane Library,  China  National  Knowledge Infrastructure (CNKI),  and  VIP Information databases between inception and  November 2020.  The medical subject headings/key- words were “extracorporeal shockwave therapy,” “frozen shoulder,” “randomized controlled trial,” and “meta-analysis.”  Variations of different terms were used to make a systematic search. The complete search strategy used in PubMed is shown in Appendix Table A1. The reference lists of relevant reviews and registered trials were also reviewed to ensure completeness of the search.

 

 

Inclusion Criteria

 

The inclusion criteria were as follows: (1) RCTs; (2) patients who were  diagnosed with frozen shoulder and  were experiencing pain and  restricted joint  movement; (3) the  experimental  groups were  treated with   ESWT  plus   routine treatments, the  control groups were  treated with routine treatments, and  the  routine treatments were  the  same in both groups; (4) there were  no restrictions on the treatment period, type of ESWT,  or  severity of symptoms, and  the energy intensity was  dependent on  the tolerance of the patient; (5) the languages were  limited to  Chinese and English; (6) whether or not  to adopt a blinded method was unlimited; and  (7) the  authors used  at least 1 of the  following  outcome indices: visual analog scale  (VAS), Constant Murley score  (CMS),  and   external rotation ROM  (ER ROM).

 

Exclusion Criteria

 

The  exclusion criteria were  as follows: (1) patients experiencing the  following  comorbidities: rotator  cuff  disease, fractures,  calcifying tendinitis, glen ohumeral arthrosis, my official pain syndrome, or other diseases that can cause shoulder pain and  dysfunction; (2) the  original data were not  suitable for a meta-analysis, and  it  was  impossible to obtain usable data by contacting the  authors; and  (3) different types of ESWT  were  compared with each  other.

 

Data Extraction

 

Two reviewers (N.Z., J.G.)  Independently screened the titles and abstracts according to the inclusion and exclusion criteria and thoroughly read the full texts of relevant literature. Studies that met the predefined criteria were included. In the case of a disagreement, a third reviewer (Z.W.) was consulted to assist in the assessment.

Another 2 reviewers (R.L., Y.H.) independently extracted the following data: first author, publication year, sample size, intervention details, follow up (where avail- able), measurement time, and outcome indices.

Pain intensity was assessed via the VAS (the lower the score, the better the effectiveness). Shoulder function was assessed via CMS (the higher the score, the better the function).  The joint ROM was assessed via ER ROM (the higher the degree, the better the curative effect).

The period of assessment was artificially defined as follows:  immediate, short-term (<3 months), and long-term (   3 months).The results at multiple follow-up times from the same study were included in the subgroup analyses by time point. When 2 studies used the same group of participants, the 2 studies were included only when different out- come measures were used.

 

Bias Assessment and Quality Classification

 

We evaluated the  quality of the  included studies using the Cochrane Collaboration’s tool for assessing risk  of bias  in randomized trials,11   using RevMan version 5.3  (Nordic Cochrane Centre, The  Cochrane Collaboration).

 

Statistical Processing and Assessment of Heterogeneity

 

For continuous variables, the mean difference (MD) or standardized MD (SMD) with the 95% CI was extracted. For dichotomous data, event ratios and sample sizes were extracted. Throughout the analyses, a 2-sided test was

 

 

†Address correspondence  to  Zhenyu Wang, MD,  Department of  Rehabilitation Medicine,  Yongchuan  Hospital,  Chongqing  Medical University, Chongqing, 402160, China (email:  This email address is being protected from spambots. You need JavaScript enabled to view it.

*Department of Rehabilitation Medicine, Yongchuan Hospital, Chongqing Medical University, Chongqing, China.

‡Department of Dermatology, Yongchuan Hospital, Chongqing Medical University, Chongqing, China. Final revision submitted August 3, 2021; accepted September 3, 2021.

One or more of the authors has declared the following potential conflict of interest or source of funding: This study was supported by funds from the

National Natural Science Foundation of China (NSFC No. 81674066); the Natural Science Foundation of Chongqing Province (No. cstc2017jcyjAX0397); the

TCM Foundation of Chongqing Health Committee of China (No. zy201602119); and the Science Foundation, Yongchuan Hospital of Chongqing Medical University (No. YJYJ201603). AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

Figure 1. Study flow diagram. ESWT, extracorporeal shockwave therapy; RCT, randomized controlled trial

 

Used, and P values   .05 were considered to be statistically significant.

Heterogeneity was evaluated by using the I2 statistic and

The Cochran Q statistic with P values.26 the data were pooled using the random-effects model if significant hetero-

 

Study Characteristics

 

The characteristics of the included studies are listed in Appendix Table A2. Patients in the adhesive phase were identified in 18 studies,kand  patients in the remaining,

 

Geneitywas present (I2 > 50% or PQ < .1); otherwise, a

 

2 studies

 

Were in the overlap of the painful freezing

 

Fixed effects model was used. In the case of significant het- erogeneity, subgroup analyses were further conducted to investigate the potential source of heterogeneity on the treatment effect size.11 the statistical software used was Rev Man 5.3 software. A descriptive analysis was performed if data could not be combined.

 

 

RESULTS

 

Study Selection

 

Initially, 200 records were identified via the electronic database search. Of these, we evaluated 121 full texts for eligibility. Ultimately, 20 RCTs§ were included in this review. The flow diagram of the selection process is shown in Figure 1.

 

Phase and adhesive phase. Two1,8 of the  included studies

Were3-arm studies, and appropriate data were selected for the statistical analysis based on the inclusion and exclusion criteria.

 

     Methodological Quality and the Risk of Bias Within Studies

 

 

The risk of bias graph and the risk of bias summary are shown in Figure 2. Of the  included studies, 18{ utilized a suitable method to minimize bias  and  were  considered to have a low risk  of selection bias,  performance bias,  detection bias,  attrition bias,  reporting bias,  and  other biases. One24 of the  included studies had  a high  risk  of bias  in the randomization scheme, and  one36  of the  included studies had  a high  risk  of other biases.

 

 

• References 1, 4-6, 8, 9, 12, 20, 24, 25, 29, 31-34, 36-39, 41.

 

kReferences 1, 4-6, 9, 12, 20, 24, 25, 29, 31-33, 36-39, 41.

{References 1, 4-6, 8, 9, 12, 20, 25, 29, 31-34, 37-39, 41.

 

 Figure 2. Risk of bias (A) table and (B) summary. a, sodium hyaluronate þ triamcinolone acetonide. Within the figure the three time points were marked as a, b and c, and relate to before treatment, immediately after treatment and 3 months after treatment.

 

Pain Intensity

 

Overall, 18 studies# assessed the post intervention effective- ness  of ESWT  plus  routine treatments compared with routine  treatments in terms of alleviating pain intensity (MD,

 

 

#References 1, 4, 6, 8, 9, 12, 20, 25, 29, 31-34, 36-39, 41.

–0.97 [95% CI, –1.13 to –0.82], P < .00001, I2 ¼ 69%). A subgroup analysis was performed based on the assessment time. Compared with routine treatments, both immediate efficacy and short-term efficacy were better. The  results were  significant and  had  low heterogeneity (immediate: MD, –1.10  [95% CI, –1.27  to –0.92],  P < .00001,  I2 ¼ 40%; short-term: MD, –0.72 [95% CI, –0.94 to –0.50],  P < .00001, I2  ¼ 39%).  However, in terms of long-term efficacy,

Figure 3. Forest plot of comparison of visual analog scale (VAS) between extracorporeal shock wave therapy plus routine treatments and routine treatments. Within the figure the three time points were marked as a, b and c, and relate to before treatment, immediately after treatment and 3 months after treatment. IV, Inverse Variance.

 

 

although ESWT  plus  routine treatments was  favored in terms of pain intensity compared with routine treatments, obvious  heterogeneity was  found, so reliable conclusions could  not  be  drawn (MD,  –0.90  [95% CI,  –1.40  to  –0.41],P < .00001, I2 ¼ 89%) (Figure 3).

 

 

Shoulder Function

 

Compared with routine treatments, the effectiveness of ESWT plus routine treatments on shoulder function after intervention was assessed in terms of CMS in 4   trials12,24,29,36   (SMD,   1.13   [95%   CI,   0.76-1.49],

P < .00001, I2 ¼ 57%). Strong evidence was detected that ESWT plus routine treatments was more effective for improving shoulder function in  terms of immediate efficacy,  with  no  heterogeneity (SMD,  1.54  [95% CI,  1.19

1.89], P < .00001, I2 ¼ 0%) (Figure 4). However, we could not draw reliable conclusions about short- and long-term efficacy.

 

 

Joint Range of Motion

 

ER ROM was used to reflect the ROM, which was assessed in 4 RCTs.5,6,9,38 Because of the limited number of studies, ER ROM was  measured immediately after treatment in  all  included studies. The pooled result of the included studies showed that the heterogeneity was high and unacceptable (MD, 10.31 [95% CI, 3.46–17.17], P < .003, I2 ¼ 93%) (Figure 5).

Figure 4. Forest plot of the comparison of Constant Murley score (CMS) between extracorporeal shockwave therapy plusroutine treatments and routine treatments. Within the figure the three time points were marked as a, b and c, and relate to before treatment, immediately after treatment and 3 months after treatment. IV, Inverse Variance; Std, standardized.

Figure 5. Forest plot of the comparison of external rotation range of movement (ER ROM) between extracorporeal shockwave therapy plus routine treatments and routine treatments. IV, Inverse Variance.

 

DISCUSSION

 

This is the first meta-analysis comparing the effectiveness of ESWT plus routine treatments and routine treatments in frozen shoulder. We  preliminarily found  that analgesic effects  (immediate and  short-term) and  function (immediate)  were  better in  the  groups where ESWT  was  used  as an  adjunct to other interventions  (immediate analgesic effects:  MD,  –1.10  [95% CI,  –1.27  to  –0.92],  P < .00001;short-term analgesic effects:  MD, –0.72 [95% CI, –0.94 to –0.50], P < .00001; immediate function: SMD, 1.54 [95% CI, 1.19 to 1.89], P < .00001,   I2 ¼ 0%).  However, for the improvement of long-term analgesia (MD, –0.90  [95% CI,–1.40 to –0.41], P < .00001,  I2 ¼ 89%) and external rotation of the shoulder joint (MD,  10.31  [95% CI,  3.46  to 17.17],

 

P < .003, I2 ¼ 93%), although there was evidence pointing to the  effectiveness of ESWT plus  routine treatments com- pared with  routine treatments, the data were  heterogeneous, and  the conclusions were not  reliable. In addition, because of the limited number of studies and  the fact that data reflecting short-term and  long-term improvement in shoulder function relied on the same RCT,29 we could  not prove that ESWT  as an  adjuvant therapy better promotes the  improvement of shoulder function.

The pathophysiology of frozen shoulder remains unclear. Although disagreements exist, cytokine-mediated synovial inflammation with fibroblastic proliferation is the most recognized explanation.22   Increased expression levels   of growth factors, cytokines, and matrix metal oproteinases are found in the patient’s capsular biopsy specimens,

 

 

 

Suggesting that these substances are involved in the inflammatory and fibrotic cascade of frozen shoulder.7

ESWT refers to a series of acoustic pulses with a certain energy density transmitted to a specific target area via an appropriate generator, thus achieving therapeutic effect.28

First, the  energy emitted via  shockwaves can  reach the affected area via body fluid  and  tissue, improve the  distribution  of  local   blood   flow,   promote  the  activation of molecular and  immunological reactions, stimulate angiogenesis, promote microcirculation, increase cell oxygen carrying, produce anti-inflammatory  effects, and  alleviate pain.10,14,15   Second, ESWT  can  up regulate nitric oxide levels, promote the  ingrowth of endothelial nitric oxide

synthase activity, and  down regulate nuclear factor kappa B expression.21  Third, shockwave therapy can  produce a cavitation effect between tissues, cause intertissue release, promote the  separation of adhesion, and  release the  adhesive  tissue.23  Fourth, this method can  change the acceptance  frequency of  nociceptors to  pain,  change  the composition of chemical mediators around nociceptors, cause changes in  free  radicals around cells,  release sub- stances that inhibit pain, and  inhibit the  transmission of pain information.10 Fifth, local  high-intensity shockwaves can  produce super stimulation  to  nerve endings, reduce nerve sensitivity, hinder nerve conduction function, and relieve pain.35  Finally, intensification of tissue regeneration, decrease in tissue apoptosis, and  effective recruitment of fibroblasts have been  observed in some  basic  studies.16

 

Study Limitations

 

There are   some potential limitations that should be addressed in this study. First, because of the time overlap, the clinical stages of disease were not completely uniform. The  vast majority were  in the  adhesive phase, and  a small number were  in  the  overlap of the  painful freezing phase and  adhesive phase. Second, because of the limited number of studies included, we were not able to perform further subgroup analysis on the results with high heterogeneity, or the studies included in subgroup analysis were insufficient, resulting in incomplete conclusions. Third, the characteristics of each included population were inevitably different, which more or less reduced the reliability and clinical applicability of the results to some extent. Clinical trials should be standardized in the future so that meta- analyses will better elaborate subgroups, including stages of frozen shoulder, main symptoms, comorbidity, and sex.

 

 

CONCLUSION

 

Although the  quality level  of the  included RCTs  was  limited,  based on  this meta-analysis, we  can  conclude that ESWT  seems to be beneficial to patients with frozen shoulder  by  alleviating pain and  improving function. ESWT could be used as an adjunct therapeutic method to routine treatments.  Considering methodological imperfections, future multicenter, prospective clinical trials with large sample sizes, placebo control, successful blinding, and effective  follow up  are  needed.

 

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40. Zhang J, Zhong S, Tan  T, et  al. Comparative efficacy and patient- specific moderating factors of nonsurgical treatment strategies for frozen shoulder: an  updated systematic review  and network meta-

analysis. Am J Sports Med. 2021;49(6):1669-1679.

41. Zhang TH, Yan RX, Sun TS, Tian YD, Zhou SH. Clinical observation of pain point  injection combined with shock wave in treating periarthritis of shoulder. Article  in Chinese. Chin  J Ctrl Endem Dis. 2016;31(11):

1248-1249.

 

 

 

 

APPENDIX

 

 

 

TABLEA1

Details of the PubMed Search Strategy

 

#1                                                                                                     Search “Frozen shoulder”[MeSH]

 

#2          Search: (((((((((((((((((((((frozen shoulder[Title/Abstract]) OR (Bursitides[Title/Abstract])) OR (Bursitis[Title/Abstract])) OR (Frozen Shoulders[Title/Abstract])) OR (Shoulder, Frozen[Title/Abstract])) OR (Adhesive Capsulitis of the  Shoulder[Title/Abstract])) OR (Shoulder Adhesive Capsulitis[Title/Abstract])) OR (Adhesive Capsulitides, Shoulder[Title/Abstract])) OR (Adhesive Capsulitis, Shoulder[Title/Abstract])) OR (Capsulitides, Shoulder Adhesive[Title/Abstract])) OR (Capsulitis, Shoulder Adhesive[Title/ Abstract])) OR (Shoulder Adhesive Capsulitides[Title/Abstract])) OR (Capsulitis[Title/Abstract])) OR (Capsulitides[Title/ Abstract])) OR (Pes  Anserine Bursitis[Title/Abstract])) OR (Bursitides, Pes  Anserine[Title/Abstract])) OR (Bursitis, Pes Anserine[Title/Abstract])) OR (Pes  Anserine Bursitides[Title/Abstract])) OR (Adhesive Capsulitis[Title/Abstract])) OR (Adhesive Capsulitides[Title/Abstract])) OR (Capsulitides, Adhesive[Title/Abstract])) OR (Capsulitis, Adhesive[Title/Abstract])

#3          Search “Extracorporeal Shockwave Therapy”[MeSH]

#4          Search: ((((((((((((((Extracorporeal Shockwave Therapies[Title/Abstract]) OR (Shockwave Therapies, Extracorporeal[Title/Abstract])) OR (Shockwave Therapy, Extracorporeal[Title/Abstract])) OR (Therapy, Extracorporeal Shockwave[Title/Abstract])) OR (Shock Wave  Therapy[Title/Abstract])) OR (Shock  Wave  Therapies[Title/Abstract])) OR (Therapy, Shock  Wave[Title/Abstract])) OR (Extracorporeal Shock  Wave  Therapy[Title/Abstract])) OR (Extracorporeal High-Intensity Focused Ultrasound Therapy[Title/ Abstract])) OR (Extracorporeal High  Intensity Focused Ultrasound Therapy[Title/Abstract])) OR (HIFU Therapy[Title/Abstract])) OR (HIFU Therapies[Title/Abstract])) OR (Therapy, HIFU[Title/Abstract])) OR (High-Intensity Focused Ultrasound Therapy[Title/Abstract])) OR (High  Intensity Focused Ultrasound Therapy[Title/Abstract])

#5          Search (randomized controlled trial[Publication Type]OR randomized[Title/Abstract] OR placebo[Title/Abstract])

#6          #1 OR #2

#7          #3 OR #4

#8          #5 AND #6 AND #7

 

 

 

TABLEA2

Basic Features of the Included Studiesa

 

	Sample
	Size
Lead  Author	(ESWT/			Intervention		Measurement
(Year)	Control)	ESWT  Group	Control Group	Time	Follow-up	Time	Outcomes

 

Cai (2019)1            40/40      ESWT þ pain point injection þ intra-articular injectionb þ manual therapy

 

Pain point injection þ intra-articular injectionb þ

manual therapy

 

2 wk                                3 mo        Before treatment and  3 mo after treatment

 

VAS

 

Chen (2014)4       35/35      ESWT  (1500 shockwaves, 10 Hz,

1.5 bar)  þ manual therapy

Choi (2017)5         11/10      ESWT  (800 impulses, 5 Hz,

0.129  mJ/mm2) þ kinesio taping

 

Manual therapy        Once every  6 d for

20 d

Kinesio taping           Twice a wk for

4 wk

 

NR         Before  and  after treatment

NR         Before  and  after treatment

 

VAS

 

ER ROM

 

Deng (2019)6        31/31      ESWT (2000 waves, 8 Hz,

1.0 bar) þ ultra-short-wave therapy þ joint loosening

 

Ultra-short-wave therapy þ joint loosening

 

Once every 6 d for

30 d

 

NR         Before and after treatment

 

VAS, ER ROM

 

Ding (2013)8         65/63      ESWT (2000 shockwaves,

4.5 J) þ massage

 

Massage                    3   /wk (10    total)       NR         Before and after treatment

 

VAS

 

Gao (2013)9           30/29      ESWT (600-2000 shocks,

12-15 Hz, 1.6-2.5 bar) þ

routine rehabilitation therapy

 

Routine rehabilitation therapy

 

Once a wk for

3 wk

 

NR         Before and after treatment

 

VAS, ER ROM

 

Huang

(2014)12

 

24/24      ESWT (1000 impulses,

0.18-0.25 mJ/mm2) þ routine rehabilitation therapy

 

Routine rehabilitation therapy

 

Once a wk for

3 wk

 

NR         Before and after treatment

 

VAS, CMS

 

Li (2018)20             42/42      ESWT (1500 shockwaves, 10 Hz,

5 bar) þ manual therapy

 

Manual therapy        Once every 6 d

(2    total)

 

NR         Before and after

Treatment

 

VAS

 

Mo (2017)24          16/20      ESWT (2500-3500 waves,

10-15 Hz, 1.5-2.8 bar) þ

Warming

Qin (2013)25         23/23      ESWT (1500-2000 shocks, 6.5-11.0 kV) þ routine rehabilitation therapy

 

Warming acupuncture

 

Routine rehabilitation therapy

 

Once every 5 d for

25 d

 

Once every -7 d for 1mo

 

NR         Before and after treatment

 

NR         Before and after treatment

 

CMS VAS

 

Shao

(2020)29

 

 

 

Wang

(2017)32

 

 

Wang

(2018)31

 

27/26      ESWT (1200 shocks,0.25mJ/mm2) þ oral corticosteroid þ transcutaneous electrical nerve stimulation

63/63      ESWT (2000 waves,0.16 mJ/mm2) þ intra- articular injectionc þ manual therapy

36/36 ESWT  (2000-2500 waves, Acupuncture 3   /wk for 2 wk NR Before  and  after VAS                 1.8-2.6  bar,  8-12 Hz) þ       treatment

 

Acupuncture

 

 

Oral corticosteroid þ transcutaneous electrical nerve stimulation

Intra-articular injectionc þ manual therapy

 

Once  a wk for

6 wk

 

 

 

Once  every  2 wk for 8 wk

 

NR         Before treatment and 2, 6, and

12 wk after

treatment

NR         Before  and  after treatment

 

VAS, CMS

 

 

 

VAS

 

Wu (2017)33          53/53      ESWT (2000 shocks,0.16-2  mJ/mm2) þ intra- articular injection

 

Intra-articular injection

 

Once a wk for

3 wk

 

6 wk        Before treatment and  6 wk after treatment

 

VAS

 

Xie (2019)34          43/44      ESWT (2000 shockwaves,

8 Hz) þ manual therapy

Xu (2016)36           40/40      ESWT (1000 shockwaves, 10 Hz,

0.18-0.25 mJ/mm2) þ manual therapy

 

Manual therapy        Once every 5 d for

20 d

Manual therapy        Once  a wk (20 d total)

 

NR         Before and after treatment

NR         Before and after treatment

 

VAS

 

VAS, CMS

 

Yang

(2017)37

 

26/26      ESWT (1000-1500 shocks,

50-60 Hz) þ routine rehabilitation therapy

 

Routine rehabilitation therapy

 

Once every 5 d

(3    total)

 

NR         Before and after treatment

 

VAS