Methods

Randomised controlled trial
Randomisation: The sequence of random allocation to either active or sham ESWT was determined using block randomisation with random block sizes of 2, 4 and 6. Sequence generation and concealment were performed by a person otherwise uninvolved in the study. Randomisation was stratified according to whether subjects were unilaterally or bilaterally affected. Numbered opaque envelopes were used to conceal allocation.
Blinding: both participants and outcome assessor were blinded to treatment allocation. Participants were not aware there was a sham protocol involved but were informed the study was comparing two different treatment protocols. This deception was performed to preserve subject blinding because of widespread accessibility of information on ESWT protocols, in particular information regarding discomfort during therapy. This was approved by the Conjoint Health Research Ethics Board at the University of Calgary.
Loss to follow‐up: 4 (6.7%) participants were lost to follow up (2 participants (1 in each group) did not attend the 8‐week follow‐up; 1 participant in the placebo group did not attend for therapy (and so presumably did not provide any post‐baseline data; and 1 participant also in the placeo group is stated to have not noted any improvement but it is not clear whether this participant provided any post‐baseline data.
Sample size reported: a sample size of 30 participants per group was calculated to be able to provide sufficient power (a=0.05, 1‐ß=0.8) to detect a 2‐fold difference in the proportion of treatment successes at 8 weeks (5 weeks after the completion of treatment), assuming that 20% of the placebo group would have a treatment success (i.e. 60% success rate in the active group), allowing for a 20% dropout/loss to follow up rate.
Appropriate statistical analysis: yes, intention to treat analysis. Last observation carried forward was used for missing outcome data.

Participants

60 (1 withdrew prior to treatment) participants
Inclusion criteria: lateral elbow pain; aged 18 years or older; less than 1 year since onset of symptoms; more than 3 weeks since onset of symptoms; tenderness over the lateral epicondyle and common extensor origin tendons; pain worsened with resisted wrist extension and hand grip; pain worsened with elbow extension, forearm pronation, wrist palmar flexion; willing to discontinue bracing; informed consent form signed.
Exclusion criteria: history of active treatment for lateral epicondylitis (past or present); posterior interosseous nerve compression; traumatic injury to the affected elbow; Workers' compensation board claimants; elite athletes; systemic rheumatologic condition (eg: rheumatoid arthritis, Reiter's syndrome); contraindications for extracorporeal shock wave therapy including evidence of nerve or nerve root irritation, pregnancy, blood coagulation disorder, presence of bony or articular lesions in the elbow (radiographically determined; calcific tendinitis acceptable), malignant disease, subjects with pacemakers.

Interventions

Group 1 (active ESWT) (31 participants): 3 treatment sessions for each affected arm (one each week for 3 weeks). Treatments were applied using a low energy shock wave machine (Sonocur Basic (Siemens AG, Erlangen, Germany)). Conducting gel was applied to the site of pain and the treatment head of the machine placed on the point of maximum pain as identified by the subject. Subjects received 2000 pulses of 0.03 to 0.17 mJ/mm2 per affected arm in each session. The energy flux density used to treat each subject was determined by the subjects own pain tolerance, as per the manufacturer's protocol.
Group 2 (Placebo ESWT) (28 participants): 3 treatment sessions for each affected arm (one each week for 3 weeks). Before administration of the therapy, an air buffer pad was placed between the head of the machine and the skin of the subject's elbow. Conducting gel was applied to the elbow, and the head of the machine was placed on the lateral epicondyle. The treatment technician administered 2000 pulses of 0.03 mJ/mm2, none of which was transmitted to the subject's tissues owing to the air buffer pad.
All subjects were educated on a simple stretching program at their initial visit as part of their treatment protocols. The program consisted of a single forearm extensor stretch. Subjects were instructed to perform 4 repetitions, holding the stretch for 20 seconds, 4 times a day. This was to address the potential for flexion contractures.

Outcomes

Outcome assessed at baseline, 4 and 8 weeks after initiation of therapy i.e. baseline and 1 and 5 weeks after the completion of treatment).
1) Pain on 10cm VAS where 0 = no pain and 10 = worst pain imaginable ‐ overall pain, resting pain, pain during sleep, pain during the subject's main activity, pain at its worst, and pain at its least
2) Quality of life assessed using thermometer subsection of the EuroQol 5D quality of life instrument.
3) Pain free maximum grip strength measured using a dynamometer. Subjects were tested in a standing position, with the elbow at 90° of flexion and were instructed to squeeze until discomfort was felt at the lateral epicondyle. Each subject performed the grip test three times on each arm.
4) Pain medication log: All patients were instructed to keep a pain medication log, recording medication taken, the dosage, date it was taken, and why it was taken (eg. for a headache, for elbow pain).
5) Adverse effects. These were classified as mild, moderate or severe.
The primary outcome was treatment success and failure. Treatment success was defined a priori as fulfilment of all of the following 3 criteria (1) at least a 50% reduction in overall elbow pain as measured by overall pain VAS, (2) maximum allowable overall elbow pain score of 4.0cm, and (3) no use of pain medications for lateral elbow pain for 2 weeks before the 8 week evaluation. Treatment failure was defined as a lack of a treatment success. In bilaterally affected subjects, fulfillment of all 3 success criteria in both arms was required for classification as a treatment success.
All patients were instructed to keep a pain medication log, recording medication taken, the dosage, date it was taken, and why it was taken (eg. for a headache, for elbow pain).

Notes

Median values and interquartile ranges were presented in tabular format (and are shown in Additional tables 04).
Mean values were presented in graphical format with error bars representing standard error of the mean. The trial authors declined our request to provide further data from the graphs in view of concerns that the distribution of values in their data set was not normally distributed. Therefore the study was included in the review but only the proportion of participants with treatment success could be included in the meta‐analysis.
The authors reported no significant difference between the two treatment groups for any of the measured outcomes at any timepoint (Additional tables 04) and hence the results are consistent with the conclusion of the review.
Used Sonocur Basic (Siemens, Germany).
Acknowledgements: Funding and support were provided by a grant from the Sports Science Association of Alberta and by the Alberta Provincial Canadian Institutes of Health Research Training Program in Bone and Joint Health.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Low risk

A ‐ Adequate

Methods

Randomised controlled trial
Randomisation: closed unmarked envelopes
Blinding: participants were not blinded. Unclear whether outcome assessment was blinded.
Loss to follow‐up: 48/51 randomised to ESWT completed treatment; 25/42 randomised to steroid injection received injection and 17/42 refused injection after randomisation. Loss to follow up after intervention not reported.
Sample size not reported.
Appropriate statistical analysis: all patients who were randomised and completed treatment were included in the analysis of success at 3 months after the end of treatment.

Participants

93 participants
Inclusion criteria: aged 18 years or over; classic history of tennis elbow for longer than 4 months; no surgical intervention or injection in the previous year; positive clinical findings of tenderness over the lateral epicondyle of the humerus and reproducible pain with resisted finger and wrist extension.
Exclusion criteria: evidence of dysfunction of the shoulder, neck or thorax; local arthritis; generalised polyarthritis; generalised neurological abnormality; nerve entrapment in the upper limb; pregnancy; infection; tumour; clotting disorder; anticoagulant therapy; cardiac pacemaker.

Interventions

Group 1 (steroid injection group): injection of 20mg of triamcinolone (made up to 1.5ml with 1% lignocaine) into the point of maximal tenderness at the extensor origin of the lateral epicondyle of the humerus.
Group 2 (ESWT group): 3 sessions of ESWT at weekly intervals given by an ultrasonographer from United Medical Systems using the portable Storz Minilith SL1 lithotripter. Total of 2000 shock waves (maximum 0.1 mJ/mm2) was administered at each session with inline ultrasound guidance. No patient required local anaesthesia.
Both groups advised to rest and moderate their activities to avoid aggravation of their symptoms.

Outcomes

Outcome assessed at baseline, 6 weeks and 3 months after the end of treatment (i.e 6 weeks and 3 months from baseline in steroid group but 8 weeks and 3.5 months from baseline in ESWT group.
1) Visual analogue pain score (0 no pain to 100 the worst pain imaginable)
2) reduction of pain of 50% as criterion of success at three months after the end of treatment

Notes

Mean pain values were presented without any measured of variance. Therefore the study was included in the review but only the proportion of participants with a reduction in pain of 50% at 3 months could be included in the meta‐analysis (noting that the timing of the 3 month assessment was 3.5 months in the ESWT group).
The authors reported a non‐significant difference between treatment groups favouring steroid injection for mean pain at 6 weeks after the end of treatment (67 to 21 in the steroid injection group, 61 to 35 in the ESWT group, p = 0.0520. At 6 months after the end of treatment mean pain score was 12 and 31 in the steroid injection and ESWT groups respectively (mean pain scores are presented in Additional tables 03).
Acknowledgements: no benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Unclear risk

B ‐ Unclear

Methods

Multicentre randomised controlled trial
Randomisation: permuted blocks of 6 and 4, stratified by centre
Blinding: both participants and outcome assessors were blinded
Loss to follow‐up: 9% of total number of participants. 10 (7.5%) in ESWT group and 15 participants (10.9%) in placebo group.
Sample size reported: 20% difference in primary endpoint (success of therapy at 12 weeks)
Appropriate statistical analysis: yes, intention to treat analysis

Participants

271 participants (1 participant withdrew prior to the intervention)
Inclusion criteria: Epicondylitis of the radial humerus (at least 2 positive clinical tests); Roles and Maudsley score of 3 or 4; at least 6 months of unsuccessful conservative therapy with at least 3 local injections plus at least 10 individual treatments with physiotherapy plus at least 10 individual treatments of physical forms of therapy; at least a 2 week interval since the last conservative therapy; written informed consent.
Exclusion criteria: Local arthrosis /arthritis or rheumatoid arthritis; pathological neurological findings in the upper extremity to be treated (e.g. entrapment of cervical nerves, cervical disc herniation, supinator syndrome, carpal tunnel syndrome); previous operation on epicondyle in upper extremity to be treated; bilateral symptoms; under 18 years of age; pregnancy; thrombopathy, anticoagulant therapy or manifest hyperthyroidosis; infection or tumour of upper extremity to be treated; known allergy to local anaesthetic (mepivacaine [Scandicain]).

Interventions

Group 1 (ESWT group) (135 participants): "Low energy" ESWT with 3 treatments of 2000 pulses at ED+ = 0.07‐0.09 mJ/mm2. 6‐8 days between each treatment. Performed under local anaesthesia (3ml, 1% mepivacaine). Positioning was performed with the use of continuous ultrasound imaging to focus the shock waves at the insertion of the muscles at the lateral epicondyle of the humerus.
Different shock wave devices were used at the various centres and lithotripsy manufacturers worked out set of comparable shock wave parameters.
Group 2 (placebo group) (137 participants): same regimen of ESWT as above under local anaesthesia but a polyethylene foil filled with air and fixed with ultrasound gel in front of the coupling cushion totally reflected the shock waves.

Outcomes

Outcome assessed at baseline, 6 and 12 weeks and 12 months after last intervention.
Primary end point: Success rate after 12 weeks defined as subjective pain scale described by Roles and Maudsley was 1 or 2 and the patient didn't receive any additional conservative or operative treatment in observed time interval.
Secondary end ponts:
1) Roles and Maudsley score
2) Intensity of pain on an 11 point scale (0 = no pain, 10 = unbearable pain).
3) Grip strength (Bowden test)
4) Side effects and adverse reactions

Notes

Roles and Maudsley subjective pain scale: 1 = excellent (no pain, full movement and activity), 2 = good (occasional discomfort, full movement, full activity), 3 = fair (some discomfort after prolonged activity), 4 = poor (pain limiting activities).
To enable pooling with Rompe trial data, we also extracted 'failure' defined as Roles and Maudsley score of 4 (poor).
Mean pain scores and SD were converted to 0‐100 scale by mulitplication by 10.
Sponsorship: none reported. Acknowledgments: Deutsche Forshungsgemeinschaft (DFG), Grant Number: 1079/2‐1,
German Association for Orthopaedics and Traumatology (DGOT), Frankfurt
Verein zur Förderung von Wissenschaft und Forchung eV (Association for Promoting Science and Research) at the Rehberg Clinic, Germany
Storz Medical AG, Kreuslingen, Switzerland
Siemens AG, Erlangen, Germany
Richard Wolf GmbH, Knittlingen, Germany
Dornier who put shock wave equipment at their disposal.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Low risk

A ‐ Adequate

Methods

Randomised multi‐centre placebo‐controlled trial (number of sites not specified)
Randomisation method not described.
Blinding: both participants and outcome assessors were blinded to treatment allocation.
Loss to follow‐up: 18 participants (9.8%): 11 in the active treatment group and 7 in the placebo group.
Sample size calculation not reported.
Appropriate statistical analysis: Completers analysis only.

Participants

183 participants
Inclusion criteria: history of chronic lateral epicondylitis persisting for at least 6 months; failure to respond to at least 3 attempts at conservative treatment: one prior course of non‐invasive treatment, including physical therapy (e.g. stretching exercises) and the use of an orthotic device; and two prior courses of pharmacological treatment such as NSAIDs or cortisone injections; investigator assessment of pain at the point of tenderness over the affected lateral epicondyle greater than or equal to 5 on a 10cm VAS and subject self‐assessment of pain during activity greater than or equal to 5 on a 10cm VAS;
female sujects must not be pregnant; other causes of elbow pain have been ruled out, such as vascular insufficiency or neuropathy of the upper extremities; concomitant pathology has been ruled out, including severe osteoarthritis, rheumatoid arthritis, osteoporosis, metabolic disorders, malignancies, Paget's disease, an acute, subacute or chronic osteomyelitis or systemic infection, or fracture of the affected arm;
21 years of age or older to assure all subjects would be skeletally mature.

Interventions

Each subject received a local anaesthetic or a bier block prior to the study procedure. The affected arm was draped from the view of the study subject.
The HealthTronics Ossa Tron ESW electrohydraulic system was used.
Group 1 (Active group): A total of 1500 shocks was delivered at a power setting of 18kV. The average treatment time was 20.5 minutes.
Group 2 (Placebo group): A Styrofoam block was placed against the coupling membrane of the shock head to absorb the shock waves. A fluid‐filled IV bag was then placed between the Styrofoam block and the subject's elbow to mimic the feel of the coupling membrane, and 1500 shcocks were then delivered at 18kV.

Outcomes

Outcome was assessed at 4 and 8 weeks after the treatment.
1) investigator assessment of pain at the point of tenderness over the affected lateral epicondyle on a 10 cm VAS. This was performed by application of a pressure sensor to record th amount of pressure applied to ensure that the same amount of pressure was applied at each follow up assessment;
2) subject self‐assessment of pain during activitiy on a 10 cm VAS;
3) use of pain medications according to frequency of use: chronic, frequent, occasional, rare or none.
Primary endpoint was success/failure assigned at the 8‐week assessment defined as:
a minimum 50% improvement over baseline in investigator assessment of elbow pain, and a score no greater than 4 on VAS; and a minimum 50% improvement over baseline in self‐assessment of elbow pain, and a score no greater than 4 on VAS; and none or rare pain medication use defined as no more than 3 doses of medication during the week immediately prior to being evaluated. above.

Notes

Unpublished data extracted from the FDA report.
ESWT group: 47 (50.5%) women and 46 (49.5%) men; mean age 44 years (range 22‐66yrs); mean duration of symptoms = 22.5 months (range 5.3‐161.7 months).
Placebo group: 49 (54.4%) women and 41 (45.6%) men; mean age 46 years (range 32‐71 years); mean duration symptoms = 25.8 months (range 4.1‐265.9 months).
Duration of symptoms converted to months from days by the authors. Note that some participants had less than 6 months duration of symptoms (and so did not fulfil trial inclusion criteria).
Different values were provided for some of the efficacy endpoints (number who met success criteria for investigator assessment of pain at 8 weeks for the ESWT group was reported to be 43 in the text and 45 in Table 7; number who met success criteria for subject assessment of pain with activitied at 8 weeks was reported to be 48 and 36 for the ESWT and placebo groups respectively in the text and 51 and 37 for the ESWT and placebo groups respectively in Table 7; number who met success criteria for pain medication use at 8 weeks was reported to be 71 and 61 for the ESWT and placebo groups respectively in the text and 75 and 63 for the ESWT and placebo groups respectively in Table 7). The data extracted from the text was included in this review. As well, comparisons were made using intention to treat principles (i.e. all participants who entered the trial were included in the denominators where appropriate.
33 participants in the active group and 20 participants in the placebo group met criteria for success at 8 weeks (the primary endpoint). The FDA report states that there is a statistically significant difference favouring ESWT, p=0.043. However this apears to be a completers only analysis. The authors did an intention to treat analysis including all participants who entered the trial (33/93 ESWT vs 20/90 placebo) and the results were no longer statistically significant (chi‐squared=3.292, p=0.07).
HealthTronics Ossa Tron ESW electrohydraulic system.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Unclear risk

B ‐ Unclear

Methods

Randomised controlled trial
Randomisation: 100 slips of paper marked with either the letter 'T' for treatment or 'P' for placebo. Participants picked a slip of paper from a box and then the slip was replaced in the box.
Blinding: participants were blinded but outcome assessors were not blinded
No loss to follow‐up.
Sample size not reported.
Appropriate statistical analysis: yes, appears to be intention to treat analysis

Participants

24 participants
Inclusion criteria: lateral epicondylitis; failed one or more of the following methods of treatment: topical NSAIDs, steroid injection and/or surgery; written informed consent
Exclusion criteria: none listed

Interventions

Group 1 (ESWT group) (13 participants): 2000 shock waves at 2.5 bars of air pressure and frequency of 8‐10 Hz. Three treatments given at intervals of 2 weeks, each lasting for 3‐4 minutes. Electro Medical Systems (EMS) Swiss DolorClast System used.
Group 2 (placebo group) (11 participants): received treatment with the clasp on the elbow which intercepted by the clasp.
All participants in both groups received 3‐5 ml of 1% lignocaine at the site of maximal tenderness.

Outcomes

Outcome assessed at baseline, 3 and 6 months after the final treatment but only the 6 month data was reported.
1) Pain on visual analogue scale (VAS) of 0‐10. An improvement in score by 3 points was considered to be significant.

Notes

Trial also recruited 23 participants with plantar fasciitis. Data presented separately for the two conditions.
No measures of variance were given for the mean pain scores therefore only the proportion of participants who improved by 3 or more points at 6 months could be included in the meta‐analysis (mean pain scores are presented in Additional tables 02).

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

High risk

C ‐ Inadequate

Methods

Randomised controlled trial
Randomisation method not described.
Blinding: both participants and outcome assessors were blinded
Loss to follow‐up: 12/86 patients (14%)
Sample size calculation not provided.
Appropriate statistical analysis: no, completers analysis only

Participants

86 participants randomised but only 74 participants completed treatment and were included in analysis.
Inclusion criteria: pain localised to lateral epicondyle; tenderness over lateral epicondyle, the supracondylar ridge and the first 2cm of the extensor muscle mass; previous conservative treatment (physiotherapy or steroid injection); increased pain on resisted wrist extension; increased pain on elbow extension with full wrist flexion. (for inclusion, at least the first 3 and at least one of the last 2 criteria must be fulfilled)
Exclusion criteria: Pain over the radial and posterior interosseous nerve; positive resisted supination test; pain and tenderness located over the radiohumeral joint; exacerbation of pain on movement of the neck; sensory disturbance in the affected arm but not a previous carpal or cubital tunnel syndrome with complete resolution of symptoms; previous surgery for lateral epicondylitis or radial nerve entrapment; a history of fracture of the affected elbow ; age below 18 years; coagulation disorders; untreated infections of the involved arm; apparent hyperthyroid state; tumours of the limb; pregnancy.

Interventions

Group 1 (ESWT group) (37 participants): shock waves were focussed on the common extensor origin under ultrasound guidance. Ultrasound gel used as conductive medium between the skin and treatment head. All treatment sessions were started at a low energy level (1‐3) and the intensity was gradually increased according to each participant's tolerance, not exceeding level 6. A fixed amount of energy (333 mJ/mm2) was delivered at each session, totalling 1000 mJ/mm2 at the end of 3 sessions.
Group 2 (Control group) (37 participants): A foam pad which acted as a reflective medium by virtue of its air bubbles was placed between the treatment head and the skin. All aspects of the treatment including seating, positioning of the arm with imaging on the ultrasound screen and operation of the shock wave generator were identical for both groups.

Outcomes

Outcome assessed at baseline, 1, 3 and 12 months after end of treatment.
1) Disabilities of Arm, Shoulder and Hand (DASH) function/symptom score
2) Mean pain (on VAS) in a typical week, and on lifting a 5kg dumbbell.
3) Grip strength (measured by a JAMAR dynamometer)
4) Analgesic requirements
5) End point defined as either surgery for tennis elbow as originally planned or a request to be removed from the surgical waiting list.

Notes

Mean values were presented in graphical format but without any measure of variance. Therefore the study was included in the review but only the proportion of participants eventually requiring surgery could be included in the meta‐analysis. The authors reported no significant difference between the two treatment groups for any of the measured outcomes at any timepoint and hence the results are consistent with the conclusion of the review.
An orthopaedic extracorporeal shock wave generator was used with an out‐of‐line ultrasound probe for navigation (Dornier Epos Ultra: Dornier MedTech GmbH, Wessling, Germany)
Acknowledgements: Dornier, Medizintechnik, and the BUPA Research Fund for supporting the study.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Unclear risk

B ‐ Unclear

Methods

Randomised multi‐centre placebo‐controlled trial (3 sites) but open cross‐over to active treatment if not improved by at least 50% with respect to pain elicited by Thomsen test at 12 weeks following completion of treatment.
Randomisation method not described. At randomisation each participant was given a unique study number and a sealed envelope with their study number on it. The sealed envelope contained the randomisation code (A or B) which was only opened by the shock wave operator and not shared with anyone else in the study.
Blinding: Both participants and outcome assessors were blinded to treatment allocation but were unblinded at 12 weeks following completion of the treatment if participants had failed to improve by at least 50% from baseline with respect to pain elicited by the Thomsen test. Participants in the placebo group were then offered the active treatment
Loss to follow‐up: 6/114 participants were lost to follow up prior to the 12 week primary endpoint (3 in each group). An additional 38/58 participants (66%) in the placebo group and 19/56 participants (34%) in the active ESWT group were considered treatment failures at 12 weeks post‐treatment and would have been unblinded at this time and could receive either active treatment (34/38 participants who had initially received placebo) or other standard therapies (for those who had initially received active ESWT treatment).
Sample size reported: a sample size of 45 participants per group was calculated to be able to provide sufficient power (a=0.05, 1‐ß=0.8) to demonstrate a 30% difference between the proportion of participants who improved by at least 50% from baseline to 12 weeks after the completion of treatment assuming a 50% success in placebo (80% success in active ESWT). Assuming a retention rate of at least 80%, they recruited a total of 114 participants.
Appropriate statistical analysis: yes, intention to treat analysis.

Participants

114 participants
Inclusion criteria: history of lateral epicondylitis for a minimum of 6 months with pain that was resistant to at least two of three conventional therapies. These included: greater than 4 weeks of physical/occupational therapy, a greater than 4 week course of non‐steroidal anti‐inflammatory medication (NSAIDs) and corticosteroid injections. Participants also had to have tenderness on palpation of the lateral epicondyle, and reproducible pain provoked by wrist extension (the Thomsen test) greater than or equal to 40 on a 100mm VAS.
Exclusion criteria: age < 18 years; history of a lateral elbow injection within the prior 6 weeks; physical therapy within the prior 4 weeks; NSAIDs or acetaminophen use for any reason within 1 week prior to the study; active bilateral epicondylitis; anticoagulation; history or findings of cervical spondylosis, upper extremity arthritis, elbow arthrosis by x‐ray, neurologic abnormality, rheumatoid disease or radial nerve entrapment; participants receiving worker's compensation; prior surgery for lateral epicondylitis; severe systemic disease; pregnancy.

Interventions

Group 1 (ESWT group) (56 participants): 2000 impulses at 0.06mJ/mm2 using Sonocur ESWT system (Siemens, USA) weekly for 3 weeks. The treatment head of the device was directed to the point of maximal tenderness on the lateral epicondyle as identified by physician palpation and patient report. An ultrasound coupling gel was used. During treatment, the technique of clinical focussing was employed by adjusting the shock wave focus every 200‐400 impulses, redirecting the shock waves to the most symptomatic site.
Group 2 (placebo ESWT) (58 participants): 2000 impulses at 0.06 mJ/mm2, but using a sound‐reflecting pad between the patient and the application head of the machine.
No local anaesthesia used for either group.

Outcomes

Outcome was assessed at baseline, 1, 4, 8, 12 weeks and 6 and 12 months after completion of treatment (i.e. 3, 6, 10, 14 weeks and 6.5 and 12.5 months from baseline).
1) Thomsen provocation test measured on 100mm VAS (see Notes for how Thomsen test was performed).
2) Upper Extremity Functional Scale (UEFS)(see notes)
3) Subjective patient evaluation of their disease status scored on 100mm VAS.
4) Patient‐specific Activity score: patients rated their difficulty from 1 (no difficulty) to 10 (can't perform) for 2 patient‐identified activities that they found particularly difficult to perform (activities were chosen from the UEFS). The patient‐specific Activity score was the average of these 2 ratings (range 1‐10).
5) Grip strenght (Jaymar Dynomanometer)
6) Adverse effects (only pain and nausea are included in this review. A full list of adverse effects is provided in Table 3 of the paper).
The primary efficacy endpoint was a 50% reduction in the provocation of pain by Thomsen test at 12 weeks following completion of treatment compared to baseline.

Notes

The Thomsen test was performed with the shoulder flexed to 60 degrees, the elbow extended, the forearm pronated and the wrist extended to 30 degrees. Pressure was applied on the dorsum of the hand to stress the extensor carpi radialis and brevis. The test was performed 3 times, with participants recording their pain on a 10cm VAS after the third test.
The Upper Extremity Functional Scale (UEFS) consists of 8 activities (sleeping, writing, opening jars, picking up small objects with fingers, driving more than 30 minutes, opening a door, carrying a milk jug from the refrigerator, washing dishes). Each activity is given a score from 1 (no difficulty) to 10 (cannot perform). The UEFS score is calculated by summing the responses (range 8‐80) but in this study individual scores were summed and averaged (range 1‐10). The authors mutiplied the mean (SD) by 8 to derive the summed score as per the original scale for the purpose of pooling.
Treatment code was broken at 12 weeks if participants did not have at least 50% reduction in pain from baseline. If the participant had received placebo and still fit the inclusion criteria, they could then receive the active treatment. They were followed up for a further 12 weeks but were considered 'lost' to the placebo group. If the participant had received the active treatment and failed treatment other standard treatments could be considered. Only data up to the 12‐week assessment are included in this review.
For the purposes of metaanalysis, success was defined as the proportion of participants with a 50% reduction in provocation of pain by Thomsen test (the primary efficacy endpoint).
ESWT system (Siemens, USA)
ESWT group: 29 (51.8%) women and 27 (48.2%) men; mean age 47 years (range 35‐71yrs); mean duration of symptoms = 21.3 months (range 6‐178 months).
Placebo group: 31 (53.4%) women and 27 (46.6%) men; mean age 47.3 years (range 35‐60 years); mean duration symptoms = 20.8 months (range 6‐176 months).
Acknowledgements: none
The authors would like to thank Drs Pettrone and McCall who kindly provided their paper for inclusion in this review.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Low risk

A ‐ Adequate

Methods

Randomised controlled trial
Randomisation method not described.
Blinding: both participants and outcome assessors were blinded
Loss to follow up: 15/115 (13.0%) patients dropped out and were not accounted for in the analysis. Treatment allocation of these 15 patients was not reported.
Sample size calculation not reported.
Appropriate Statistical Analysis: No, only those who completed trial were included.

Participants

115 participants
Inclusion criteria: pain over lateral epicondyle for more than 12 months and unsuccessful treatment during the previous 6 months. In addition pain reproduced by at least 2 of the following: 1) palpation of the lateral epicondyle; 2) resisted wrist extension (Thomsen test); 3) resisted finger extension; and 4) Chair test.
Exclusion criteria: under 18 years of age; dysfunction of the shoulder, neck and/or thoracic region; local arthritis; generalised polyarthritis; neurological abnormalities; radial nerve entrapment; pregnancy; infections or malignancy; or reduced range of movement at the elbow.

Interventions

Group 1 (Experimental group): ESWT 1000 impulses of 0.08mJ/mm2 at weekly intervals for 3 weeks
Group 2: Control group: 10 impulses of 0.08mJ/mm (subtherapeutic) at weekly intervals for 3 weeks.
Treatment was administered at the anterior aspect of the lateral epicondyle and at 3 points around this site at a radius of 1.5 to 2 cm at a frequency of 3 Hz

Outcomes

Assessments were made at baseline (6 weeks before treatment), at end of 3‐week treatment (0 weeks) and at 3, 6 & 24 weeks after the completion of treatment.
Outcomes assessed:
1) Pain was measured on VAS ranging from 0 = no pain to 100 = maximal pain. Pain was categorised as night pain; pain at rest; pain with palpation over lateral epicondyle; pain with resisted wrist extension (Thomsen test)(with shoulder flexed to 60 degrees, elbow extended, forearm pronated and wrist extended about 30 degrees, pressure is applied to dorsum of 2nd and 3rd metacarpal bones in direction of flexion and ulnar deviation to stress extensor carpi radialis brevis and longus); pain with resisted middle finger extension (with shoulder flexed to 60 degrees, elbow extended, forearm pronated and fingers extended, the middle finger is actively extended against resistance); and pain with Chair test (with shoulder flexed to 60 degrees and elbow extended the patient attempts to lift a chair weighing 3.5 kg).
2) Overall outcome defined by level of residual pain at end of 12‐week follow up, according to Roles and Maudsley criteria (ranging from 1 excellent, 2 good, 3 acceptable and 4 poor) (see notes for Haake trial for definitions)
Failure defined by authors as Roles‐Maudsley response of 4 (poor).
3) Grip Strength measured by dynamometer & classified according to Mucha and Wannske criteria: 1 = equal strength on both sides; 2, 3, 4 = up to 25%, 50% and 75% reduction of grip strength compared with unaffected side respectively.

Notes

3 publications of identical trial design probably reporting subsets of same trial therefore reference with largest sample size and longest follow‐up reported in review.
Note failure defined in this trial as Roles and Maudsley score of 4 in comparison to trial by Haake et al who defined failure as Roles and Maudsley score of 3 or 4.
Grip strength ‐ categorical scores analysed as continuous data, therefore results not presented in review.
Siemens Osteostar (Siemens) was used to generate the shock waves.
Sponsorship: none reported.
Acknowledgments: No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Unclear risk

B ‐ Unclear

Methods

Randomised controlled trial
Randomisation: Randomization was performed according to a computer‐generated random numbers list. Only the person performing the intervention knew the treatment allocation.
Blinding: both participants and outcome assessors were blinded up until the 3‐month assessment.
Loss to follow‐up: 8 participants (10.3%)(4 in each group) and 14 participants (18.0%) (7 in each group) were lost to follow up at the 3‐ and 12‐month assessments respectively.
Sample size reported: a sample size of 35 patients per group would have >80% power in detecting a difference of 2 points in average pain rating at the 3‐month assessment (ie. assuming pain is 5 ± 2 points in the placebo group, pain will be 3 ± 2 in the active group) with a 2‐sided significance level of 0.01.
Appropriate statistical analysis: yes, intention to treat analysis.

Participants

78 participants
Inclusion criteria: playing recreational tennis (at least 1 hour per week before symptoms occurred); history of epicondylalgia of the radial humerus (at least 2 positive clinical tests) for at least 1 year; having a positive MRI (increased signal intensity of extensors); experiencing pain unresponsive (before entering study) to rest, reviewing of stroke technique and equipment by tennis professional, having undergone at least 3 conventional conservative therapy programs (including at least 3 local injections, at least 10 individual treatments of physical forms of treatment, at least 3 weeks of non‐steroidal anti‐inflammatory drug (NSAID) medication); having passed at least a 2 month interval since the last conservative treatment; experiencing baseline pain of at least 4 points on a 0 to 10 visual analogue scale (VAS) during resisted wrist extension (Thomsen Test).
Exclusion criteria: local arthrosis/arthritis; rheumatoid arthritis; cervical compression syndrome; pathologic neurological findings of the extremity to be treated; previous operation on the epicondyle to be treated; previous ESWT to any site (because of risk of unblinding); pregnancy; thrombopathy; anticoagulant therapy or manifest hyperthyroidosis; infection of the upper extremity to be treated; use of local anaesthesia during ESWT; any additional treatment between ESWT and 3 month follow up; with exception of already‐used braces.

Interventions

Group 1 (38 participants) (ESWT group): 3 treatments at weekly intervals of low energy ESWT with 3 x 2000 pulses applied using a device‐dependent energy flux density of 0.09 mJ/mm2. Repetition frequency of shock wave pulses was 4 Hz. The total dose applied was 0.54 mJ/mm2.
Prior to treatment, a coupling gel was applied to the treatment area (sore area near or over lateral epicondyle identified by palpation and marked with a pen). Initially shockwaves were delivered at the lowest energy level. Energy level was increased to 0.09 mJ/mm2 within 100 pulses.
Group 2 (40 participants) (placebo group): received the same regimen of placebo ESWT. A polyethylene foil filled with air and fixed with ultrasound gel in front of the coupling cushion completely reflected the shock waves. The typical sound created by the lithotripter remained constant.
All patients in both groups were advised to stop playing tennis until 1 week after the last ESWT treatment. Participants were able to continue wearing braces already used for the treatment of the epicondylitis. No other therapies (including massage, chiropractic, laser, splint, acupuncture, any pain medication, or oral, topical or locally injected corticosteroids) were allowed until 3 month follow up.

Outcomes

Outcome assessed at baseline, 3 and 12 months after last treatment.
1) Pain on 10cm VAS during resisted wrist extension (Thomsen Test)
2) Number of participants with at least a 50% improvement in pain with resisted wrist extension (Thomsen Test)
3) Roles and Maudsley Score: 1 = excellent, no pain, patient satisfied with treatment outcome; 2= good, symptoms significantly improved, patient satisfied with treatment outcome; 3= acceptable, symptoms somewhat improved, pain at a more tolerable level than before treatment, patient slightly satisfied with treatment outcome; 4 = poor, symptoms identical or deteriorated, patient not satisfied with treatment outcome.
4) Upper Extremity Function Scale: self‐administered 8‐item questionnaire used to measure the impact of upper extremity disorders on a person's ability to perform physical tasks. The rating of each task ranges from 1 to 10 points where 1 point indicates no problems with completing the task and 10 indicates a major problem or inability to complete. The physical tasks rated are sleeping, writing, opening jars, picking up small objects with fingers, driving car more than 30 minutes, opening a door, carrying a milk jug from fridge, washing dishes. The UEFS score is the sum of all responses (range 8‐80).
5) Maximum grip strength: assessed using Jamar dynamometer. Units in kg/cm2.
6) Overall satisfaction: all patients asked if they were able to perform activities at the desired level and to continue playing recreational tennis.
7) Adverse Effects
The primary efficacy endpoint was defined pain elicited during resisted wrist extension (Thomsen test) at 12 weeks following completion of treatment compared to baseline. A relevant clinical improvement was defines as >30% decrease of pain ratings.

Notes

The Thomsen Test data was converted to 100mm VAS scale for the purpose of pooling of data.
Data (mean and SD for grip strength and numbers in each Roles and Maudsley category) was kindly provided by Dr. Rompe.
Sonocur Plus, Siemens AG, Erlangen, Germany. Electromagnetic shock waves.
ESWT group: 18 women and 20 men; mean age 45 (range 23‐69yrs); mean duration of symptoms = 24 months (range 12‐120 months).
Placebo group: 20 women and 20 men; mean age 45 years (range 18‐68 years); mean duration symptoms = 25 months (range 12‐132 months).
Acknowledgements: Drs Pettrone and McCall kindly provided their paper for inclusion in this review.

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Low risk

A ‐ Adequate

Methods

Randomised controlled trial
Randomisation method not described.
Blinding: both participants and outcome assessors were blinded
Loss to follow‐up: 4/75 (5.3%) patients lost to follow up
Sample size calculation not reported
Appropriate statistical analysis: yes, intention to treat analysis

Participants

75 participants
Inclusion criteria: age over 18 years; unilateral lateral elbow pain for at least 3 months; point tenderness at or near the common extensor tendon insertion at the lateral epicondyle and pain at the lateral epicondyle reproduced with resisted extension of the middle finger distal to the proximal interphalangeal joint.
Exclusion criteria: additional elbow pathology including instability, arthritis or any local dermatological problem; generalised polyarthritis; neurological abnormalities; anticoagulant therapy; treatment to the affected area within the previous six weeks; pregnancy; diabetes; connective tissue or infectious disease; vasculitis; malignancy.

Interventions

Group 1 (ESWT group) (40 participants): 1500 pulses at 0.18 mJ/mm2 applied. Target area was located via ultrasonographic localisation and finding the area of maximum reproduction of local pain at initiation of the treatment.
Group 2 (Control group) (35 participants): minimal energy pulses of 0.04mJ/mm2 were generated in order to create the same sound as the ESWT group. The treatment head was deflated, no coupling gel was applied and contact with the skin was avoided.
Three treatments at monthly intervals in both groups and no local anaesthetic was used in either group.

Outcomes

Outcome assessed at baseline and 3 months (one month after completion of therapy). Also assessed prior to each treatment, ie: at one month and 2 months.
Primary end point was final follow up at 3 months from baseline.
1) Pain (on 10cm VAS) during day and at night. A 50% improvement from baseline was considered a positive response.

Notes

All treatments using a Sonocur Plus Unit (Siemens) which generates mechanical shock waves using an electromagnetic generator.
Acknowledgements: The study was funded by the charity CARE (Cambridge Arthritis Research Endeavour).

Risk of bias

Bias

Authors' judgement

Support for judgement

Allocation concealment?

Unclear risk

B ‐ Unclear