Altered Scapulothoracic Muscle Activity in Overhead Athletes with Rotator Cuff-Related Shoulder Pain: A Systematic...

Area of Science:

• Sports Medicine
• Biomechanics
• Musculoskeletal Health

Background:

• Rotator cuff-related shoulder pain (RCRSP) is prevalent in overhead athletes.
• Scapular muscle activity plays a crucial role in shoulder function during overhead movements.
• Understanding EMG differences in these athletes is vital for injury prevention and rehabilitation.

Purpose of the Study:

• To systematically review and meta-analyze electromyographic (EMG) activity of scapulothoracic muscles in overhead athletes with and without RCRSP.
• To compare EMG patterns between symptomatic and asymptomatic athletes.
• To assess the current evidence level regarding these differences.

Main Methods:

• Systematic search of PubMed, Web of Science, Scopus, and SPORTDiscus databases.
• Methodological quality assessment using the Joanna Briggs Institute Appraisal Tool.
• Meta-analysis using random-effects models and GRADE approach for evidence assessment.

Main Results:

• Eleven studies included 237 athletes with RCRSP and 205 controls.
• Very low-certainty evidence indicates increased upper trapezius (UT) activity (SMD=0.52) and delayed serratus anterior (SA) activation (SMD=1.01) in athletes with RCRSP.
• Decreased lower trapezius (LT) activity (SMD=-0.52) and increased UT/LT ratios (SMD=1.20) were also observed.

Conclusions:

• Overhead athletes with RCRSP exhibit altered scapular muscle activity, but the evidence is of very low certainty.
• Findings suggest an association rather than a causal link.
• High-quality prospective studies are necessary to establish causality and clinical relevance.