Table 1 Characteristics of the included RCTs

Notarnicola et al. [26]

RCT

15

15

–

–

(range: 43.0–82.0)

ESWT: Shockwaves of 2000 pulses in total were applied at 0.03 mj/mm² and a frequency of 4 Hz/s, once per week for three sessions

Control: Bridging exercise, adductor ball squeeze exercise, abdominal marching exercise and reverse curl-ups exercise (50 min), twice a week for 4 weeks

12 weeks

Kong et al. [31]

RCT

100

100

60

60

44.53 ± 8.19

ESWT: The impulse voltage is set as 7.0–9.0 kv, the impulse energy is 0.1–0.2 mj/mm², and the times of shocks are set as 1200. ESWT was conducted usually for 1–2 courses, 5 times as 1 course

Control: Laser therapeutic, once a week, with a total of 4 times

1 year

Jin et al. (2017)

RCT

15

15

8

9

53.13 ± 19.62

ESWT: With 2000 shock waves applied at each session at an intensity of 0.085–0.148 mj/mm². We repeated this procedure a total of three times, at 3-day intervals

Control: Trigger point injection

4 weeks

Eftekharsadat et al. [33]

RCT

27

27

20

17

45.04 ± 11.86

ESWT: Shockwaves of 1500 pulses with an energy flux density of 0.1 mj/mm²/min, energy level of 2–4, a frequency of 10–16 Hz, and pulse rate of 160/min in total, once a week for 5 weeks. Physical exercise: stretching exercises

Control: Trigger point injection, muscle injection of 40 mg triamcinolone + 2 mL lidocaine 2%, one session. Physical exercise: stretching exercises

4 weeks

Han et al. [30]

RCT

15

15

9

46.0 ± 8.9

ESWT: Each patient assumed a prone position, and 1000 shock waves (7 times per sec) were applied at 2.5 Hz at low energy flux densities of 0.01–0.16 mj/mm² using a 17 mm head. The treatment was conducted at the quadratus lumborum muscle and the sacroiliac joint, where the patients complained of pain

Control: Bridging exercise, adductor ball squeeze exercise, abdominal marching exercise and reverse curl-ups exercise (50 min), twice a week for 4 weeks

6 weeks

Walewicz et al. [25]

RCT

20

20

6

5

55.8 ± 9.3

ESWT: Shockwaves of 2000 pulses with the pressure of 2.5 bars (corresponding to an energy flux density of 0.1 mj/mm²), 5 Hz frequency, and treatment time of seven minutes; Physical exercise

Control: Sham shockwaves therapy; Physical exercise

12 weeks

Rajfur et al. [27]

RCT

19

18

10

10

45.4 ± 14.0

ESWT: Shockwaves of 1000 pulses with an energy flux density of 0.15 mj/mm²/min, frequency 4 Hz, twice a week for 5 weeks. Physical exercise

Control: Sham shockwaves therapy. Physical exercise

12 weeks

Elgendy et al. [28]

RCT

15

15

10

10

33.26 ± 5.48

ESWT: 2000 shocks, 0.10 mj/mm² energy, 5 Hz frequency, using a 17 mm head were administered, twice a week for 6 weeks. Stretching exercises were performed for the hamstrings, iliopsoas, and back extensors

Control: Stretching exercises were performed for the hamstrings, iliopsoas, and back extensors

6 weeks

Taheri et al. [34]

RCT

17

15

6

9

37.1 ± 11.8

ESWT: Shockwaves of 1500 pulses in total were applied at 0.15 mj/mm² and a frequency of 4 Hz/s, once a week for 4 weeks. Oral medications; stretching exercises

Control: Sham shockwaves therapy; Oral medications; stretching exercises

12 weeks

Lee et al. [29]

RCT

13

15

9

54.33 ± 13.16

ESWT: Shockwaves of 2000 pulses in total were applied at 0.10 mj/mm² and a frequency of 5 Hz/s, twice a week for 6 weeks; Williams’ exercises and McKenzie’s exercise

Control: Hot packs, and ultrasound and electrotherapy; Williams’ exercises and McKenzie’s exercise

6 weeks

Schneider [36]

RCT

15

15

–

–

43.2 (range: 23–65)

ESWT: Impulse parameters: 15–42 Hz; Myofascial trigger therapy, twice a week for 3 weeks

Control: Myofascial trigger therapy, twice a week for 3 weeks

12 weeks

Guo et al. [35]

RCT

47

44

22

25

36.0 ± 11.2

ESWT: 4000 pulses, 15 Hz, once a week for 4 weeks

Control: Medication: celecoxib and eperisone

12 weeks