Table 2 Descriptive characteristics of the included studies assessing treatments for subacromial impingement syndrome

Kardouni et al. 2015 [39]

RCT

n = 52; mean age active group 30.8 ± 11.9; mean age sham group 33.2 ± 12.6

3 of 5 positive signs or in-office exam findings

1 treatment

Pre, post & 24–48 h post-treatment

Active thoracic SMT; prone lower, mid- and seated upper thoracic treatment (x2) for a total of 6 SMT maneuvers

Sham thoracic SMT with identical positioning

NPRS^c

(0–10)

PSS^{d, b}

(0–100)

Pre-post mean change: active group, −0.9; sham group, −1.2; main effect within group (p < 0.001); between group (p = .74)

Pre-post mean change: active group, 8.6; sham group, 9.3; main effect within group (p < 0.001); between group (p = .89)

Kardouni et al. 2015 [38]

RCT

n = 45; mean age active group 31.1 ± 12.3; mean age sham group 31.2 ± 12.1

5 of 7 positive signs or in-office exam findings

1 treatment

Pre, post & 24–48 h post-treatment

Active thoracic SMT; prone lower, mid- and seated upper thoracic treatment (x2) for a total of 6 SMT maneuvers

Sham thoracic SMT with identical positioning

NPRS^e

(0–10)

PSS^{f, b}

(0–100)

Pre-post mean change: active group, −0.9; sham group, −1.5; main effect within group (p < 0.001); between group (p = .28)

Pre-post mean change: active group, 9.2; sham group, 11.0; main effect within group (p < 0.001); between group (p = .52)

Haik et al. 2014 [41]

RCT

n = 50; mean age active group 33.8 ± 12.2; mean age sham group 29.7 ± 9.3

3 of 7 positive signs or in-office exam findings

1 treatment

Pre and Post

Active thoracic SMT; seated mid-thoracic manipulation

Sham thoracic SMT

NPRS^g

(0–10)

Pre-post mean change: active group, −0.8; sham group, −0.2; main effect within group (p = .004); between group (p = .11)

Munday et al. 2007 [40]

RCT

n = 30; group A mean age 23 (range 19–32); group B mean age 22 (range 16–38)

3 of 4 positive signs or in-office exam findings

8 treatments in 3 weeks

Baseline (1^st visit), 3 weeks (8^th treatment) & 1-month follow-up

Group B (n = 15): thrust manipulation (AC joint or GH joint; if necessary, scapula or ribs)

Group A (n = 15): detuned ultrasound

VAS^h

(100 mm)

SFMPQ^h

Pre-post mean change within groups: group A, −29.17 (p ≤ .05); group B, −27.24 (p ≤ .05)

Mean differences between groups: −9.1 (p = .019)

Pre-post mean change within groups: group A, −10.77 (p ≤ .05); group B, −24.01 (p ≤ .05)

Mean differences between groups: −8.4 (p = .005)

Boyles et al. 2009 [42]

Non-randomized study

n = 56; mean age 31.2 ± 8.9

≥2 NPRS plus + Neer or Hawkins-Kennedy and ≥2 NPRS on active shoulder abduction or on resisted test (internal or external rotation; empty can)

1 treatment

Pre and Post

Thoracic SMT; seated mid-thoracic and cervicothoracic junction; supine rib manipulation (if required)

N/A

NPRSⁱ

(0–10)

SPADIⁱ

(0–100)

Pre-post mean change: Neer, −1.1 (p = .001); Hawkins, −1.2 (p < 0.001); resisted EC, −0.8 (p = .007); resisted IR,

−0.6 (p = .008); resisted ER, −1.0 (p < 0.001); active ABD, −0.8 (p = .001)

Pre-post mean change: −6.8 (p < 0.001)

Muth et al. 2012 [43]

Non-randomized study

n = 30; mean age 30.6 ± 7.9

≥3 NPRS on performance of Hawkins-Kennedy, Neer, or Jobe tests

1 treatment

Pre, post & 7–10 days post-treatment

Thoracic SMT; seated mid-thoracic (focus on apex of the thoracic kyphosis) and cervicothoracic junction

N/A

NPRS^j (0–10)

PSS^{k, b}

(0–100)

Pre-post mean change: Jobe, −2.6 (p < 0.001); Neer, −2.6 (p < 0.001); Hawkins, −2.8 (p < 0.001); cervical rotation, −0.4 (p = .04)

Pre-post mean change: 7.6 ± 9.3 CI (4.1,11.1), (p < 0.001)