# Abstract

 

## OBJECTIVES: Conflicting results were reported about the effectiveness of Low level laser therapy on musculoskeletal disorders. The aim of this study was to investigate the effectiveness of 850‐nm gallium arsenide aluminum (Ga‐As‐Al) laser therapy on pain, range of motion and disability in subacromial impingement syndrome. 

## METHODS: A total of 52 patients (33 females and 19 males with a mean age of 53.59±11.34 years) with subacromial impingement syndrome were included. The patients were randomly assigned into two groups. Group I (n = 30, laser group) received laser therapy (5 joule/cm^2^ at each point over maximum 5‐6 painful points for 1 minute). Group II (n = 22, placebo laser group) received placebo laser therapy. Initially cold pack (10 minutes) was applied to all of the patients. Also patients were given an exercise program including range of motion, stretching and progressive resistive exercises. The therapy program was applied 5 times a week for 14 sessions. Pain severity was assessed by using visual analogue scale. Range of motion was measured by goniometer. Disability was evaluated by using Shoulder Pain and Disability Index. 

## RESULTS: In group I, statistically significant improvements in pain severity, range of motion except internal and external rotation and SPADI scores were observed compared to baseline scores after the therapy (p\<0.05). In Group II, all parameters except range of motion of external rotation were improved (p\<0.05). However, no significant differences were recorded between the groups (p>0.05). 

## CONCLUSIONS: The Low level laser therapy seems to have no superiority over placebo laser therapy in reducing pain severity, range of motion and functional disability. # RESULTS Fifty two patients (33 females, 19 males) with a mean age of 53.59±11.34 years with SAIS were included in the study. All patients were able to complete the therapy program without any adverse effects. The results of complete blood count, biochemical markers, erythrocyte sedimentation rate and C‐reactive protein of the patients were found to be normal. The sociodemographic and clinic characteristics of the patients were given in [Table 1](#). No statistically significant differences were detected between the groups in initial values (p>0.05). In group I, after the therapy statistically significant improvements in pain severity, ROM except internal and external rotation and SPADI scores were observed compared to baseline scores (p\<0.05). In Group II, all parameters except ROM of external rotation were improved (p\<0.05). However, no significant differences were recorded between the groups (p>0.05) ([Table 2](#)). ::::table-wrap

::: caption
The sociodemographic and clinic characteristic of the patients.
:::

```
                                      Group I (n, %)   Group II (n, %)   p
```

______________________________________________________________________

**Age , year** (mean±SD) 53.7±12.6 53.45±9.64 0.933
**Gender**\
Female 20 (%66.7) 13(%59.1)\
Male 10 (%33.3) 9(%40.9) 0.579
**Disease duration, month** (mean±SD) 11.66±18.04 15.27±25.13 0.237
**Localization**\
Right 17 (%56.7) 12(%54.5)\
Left 13 (%43.3) 10(%45.5) 0.880
**VAS** 7.16±1.64 7.59±1.76 0.343

VAS: Visual analog scale; SD: Standard deviation.

p\<0.01

p\<0.05:::: ::::table-wrap
::: caption
Comparison of mean values of pain severity, ROM and SPADI scores before
and after the treatment between the groups.
:::

```
                               Group I          Group II         p
```

______________________________________________________________________

**VAS**\
**Baseline** (mean±SD) 7.16±1.64 7.59±1.76 0.343
**Posttreatment** (mean±SD) 3.76±1.45 4.63±2.10 0.216
**p** 0.000[\*\*](#) 0.000[\*\*](#)\
**Shoulder flexion**\
**Baseline** (mean±SD) 156±30.77 167.50±21.14 0.284
**Posttreatment** (mean±SD) 168±22.65 174.31±14.98 0.313
**p** 0.001[\*\*](#) 0.011[\*](#)\
**Shoulder extension**\
**Baseline** (mean±SD) 38.16±13.42 39.31±8.20 0.372
**Posttreatment** (mean±SD) 42.66±3.40 42.95±3.98 0.457
**p** 0.007[\*\*](#) 0.006[\*\*](#)\
**Shoulder abduction**\
**Baseline** (mean±SD) 147.16±33.52 160.68±30.71 0.145
**Posttreatment** (mean±SD) 166.66±21.38 172.72±16.67 0.140
**p** 0.001[\*](#) 0.007[\*\*](#)\
**Shoulder adduction**\
**Baseline** (mean±SD) 38.50±15.98 38.40±7.92 0.438
**Posttreatment** (mean±SD) 42.00±4.27 42.04±5.26 0.556
**p** 0.003[\*\*](#) 0.008[\*\*](#)\
**Shoulder internal rotation**\
**Baseline** (mean±SD) 47.50±9.89 47.95±5.26 0.718
**Posttreatment** (mean±SD) 49.33±9.62 49.77±4.49 0.344
**p** 0.439 0.039[\*](#)\
**Shoulder external rotation**\
**Baseline** (mean±SD) 44.16±10.09 44.77±8.23 0.752
**Posttreatment** (mean±SD) 44.83±5.64 44.09±1.97 0.517
**p** 0.205 0.480\
**SPADI~pain~**\
**Baseline** (mean±SD) 70.66±24.37 70.09±16.76 0.330
**Posttreatment** (mean±SD) 48.13±22.10 40.99±20.98 0.211
p 0.000[\*\*](#) 0.000[\*\*](#)\
**SPADI~disability~**\
**Baseline** (mean±SD) 58.12±24.36 55.17±19.02 0.282
**Posttreatment** (mean±SD) 40.54±21.40 31.87±21.08 0.115
p 0.000[\*\*](#) 0.000[\*\*](#)\
**SPADI~total~**\
**Baseline** (mean±SD) 64.39±23.65 62.63±16.58 0.236
**Posttreatment** (mean±SD) 44.33±2.80 36.39±20.53 0.201
p 0.000[\*\*](#) 0.000[\*\*](#)

VAS: Visual analog scale; SPADI: Shoulder pain and disability index; SD:
Standard deviation.

p\<0.01

p\<0.05::::


Extracted trial result:
Outcome: Shoulder Pain and Disability Index score (continuous)
Intervention: Laser therapy (Group I)
Comparator: Placebo laser therapy (Group II)
Intervention group size: 30
Intervention mean: 48.13
Intervention standard deviation: 22.1
Comparator group size: 22
Comparator mean: 40.99
Comparator standard deviation: 20.98