Specific versus general exercise programme in adults with subacromial impingement syndrome

Key points

1. 01Specific exercises produced a statistically significant but mostly sub-threshold improvement in shoulder function (SPADI difference 13.5 points; MCID is 20 points)
2. 02The largest benefit over general exercises was in reducing kinesiophobia (fear of movement), with a between-group difference of 16.3 points (large effect size, p<0.001)
3. 03Pain during movement favoured specific exercises by 1.7 cm on VAS, exceeding the 1.4 cm MCID for rotator cuff disease
4. 04Rest pain did not differ significantly between groups (between-group difference 0.2 cm, p=0.553)
5. 05Mediation analysis showed kinesiophobia and movement pain together explain how specific exercises improve shoulder function

How it was conducted

Design

Single-blind randomised controlled trial with two parallel groups, 5-week duration

Participants

52 adults with chronic subacromial impingement syndrome (symptoms >=3 months, >=3 positive clinical signs), mean age ~45 years

Experimental group

Usual care plus supervised specific exercises (scapular orientation, scapular control, glenohumeral control via low-load isometrics), 2 sessions/week for 5 weeks

Control group

Usual care plus supervised general exercises (strengthening, stretching, mobility for rotator cuff and shoulder girdle), 2 sessions/week for 5 weeks

Primary outcome

Shoulder Pain and Disability Index (SPADI, 0-100, higher = worse); MCID = 20 points

Secondary outcomes

DASH (upper limb function), VAS at rest and on movement, Tampa Scale of Kinesiophobia (TSK-17)

What they found

• SPADI between-group difference at 5 weeks: 13.5 points (95% CI: 4.3 to 15.6; eta2=0.22; p=0.001) favouring specific exercises, below the 20-point MCID
• DASH between-group difference: 10.1 points (95% CI: 5.6 to 15.2; eta2=0.27; p<0.001) favouring specific exercises, below the 11-point MCID
• VAS at rest between-group difference: 0.2 cm (95% CI: 0.1 to 0.3; eta2=0.07; p=0.553), not statistically significant
• VAS on movement between-group difference: 1.7 cm (95% CI: 0.9 to 2.2; eta2=0.24; p<0.001) favouring specific exercises, exceeding the 1.4 cm MCID
• TSK-17 kinesiophobia between-group difference: 16.3 points (95% CI: 13.2 to 15.3; eta2=0.33; p<0.001) favouring specific exercises (large effect size)
• Mediation: kinesiophobia mediated the effect of specific exercises on shoulder function (beta=2.800; 95% CI: 1.063 to 4.907); VAS on movement also mediated the effect (beta=-0.690; 95% CI: -1.176 to -0.271)
• All 52 participants completed the trial (0% dropout)

Limitations

• No follow-up beyond 5 weeks; long-term persistence of differences is unknown
• Blinding of participants and treating physiotherapists was not possible due to the nature of the interventions
• Outcomes relied on self-report questionnaires, which are subject to subjectivity and recall bias
• The study was conducted at a single centre in Chile, which may limit generalisability

Why it matters

For patients

If you have shoulder impingement with fear of movement, a targeted specific exercise programme may reduce pain and fear more than general shoulder exercises, although the practical difference after 5 weeks is modest.

For clinicians

Screening for kinesiophobia before selecting an exercise approach is warranted; patients with high fear of movement may derive greater benefit from specific low-load isometric and scapular control exercises than from general strengthening programmes.

For readers

This well-conducted RCT adds to evidence that specific exercises have a statistical edge over general exercises for subacromial impingement, but the clinical importance of the difference remains uncertain and longer-term studies are needed.