Thinking outside the shoulder: A systematic review and metanalysis of kinetic chain characteristics in non-athletes with shoulder pain

Introduction The kinetic chain is important in the proximal-distal energy transfer along body segments. Although biomechanical impairments in components of the kinetic chain have already been reported in athletes with shoulder pain, such investigations in non-athlete individuals have not yet been synthesized.Objective To systematically review the literature and analyze the quality of evidence on the characteristics of the kinetic chain of non-athletes with shoulder pain compared to asymptomatic individuals.Methods Studies published until February 2024 (without language restrictions) that quantitatively assessed outcomes related to the kinetic chain of non-athlete individuals were searched in five databases (MEDLINE, CINAHL, Web of Science, EMBASE, and SCOPUS). The risk of bias and quality of evidence were analyzed using the Joanna Briggs Institute Critical Appraisal Tool for Analytical Cross-Sectional Studies and the Grading of Recommendations, Assessment, Development, and Evaluation approach, respectively. To summarize the findings, meta-analyses with random-effects models were performed.Results Six cross-sectional studies (n = 562 [282 with shoulder pain], mean age = 48.7 +/- 8.1 years) with low risk of bias were included in this review. Very low-quality evidence suggests that individuals with shoulder pain may present a lower active range of motion and muscular endurance/strength in the cervical spine, thoracolumbar region, and hip, as well as deficits in neuromuscular control of the lower extremities. Findings related to thoracic spine posture were conflicting and no differences were found in cervical spine isometric muscular strength between individuals with and without shoulder pain.Conclusion Individuals with shoulder pain may present alterations in active mobility, muscular endurance, and neuromuscular control in kinetic chain segments. These findings suggest that broader physical assessments considering components of the kinetic chain may be clinically relevant in this population. However, based on the very low quality of evidence, the findings of this review should be interpreted with caution.