Borms D1, Vanderstukken F1, Cools A1
1Ghent University, Rehabilitation Sciences, Ghent, Belgium
Background: The prevalence of shoulder pain is high in athletes participating in overhead sports. Besides shoulder specific deficits, also non-shoulder related dysfunctions associated with shoulder pain need to be addressed. During overhead throwing, energy is built up through the kinetic chain from the lower to the upper extremity. Limited function in any of the kinetic chain segments is believed to negatively influence the energy transfer with shoulder pain as possible outcome. As a result, poor muscle flexibility, strength and balance in the lower body might negatively impact the throwing motion and potentially lead to shoulder injury. To date, there is limited evidence to support this theory.
Purpose: To study if overhead athletes with throwing related shoulder pain would show differences in proximal chain (i.e. lower body) performance compared to a healthy matched control group.
Methods: The Y balance Test - Lower Quarter (YBT-LQ), vertical (VJ) and lateral jump (LJ) performance, and hip internal and external range of motion (ROM) were investigated in 31 overhead athletes with throwing related shoulder pain on the dominant side and 31 healthy matched controls. A linear mixed model was applied to determine significant differences in YBT-LQ, LJ and hip ROM test scores between groups (pain group or control group) and sides (dominant or non-dominant). An independent T-test was used to examine group differences in VJ performance.
Results: Results show no group or side differences for any of the included tests except for the YBT-LQ anterior reach: the control group reached significantly further than the pain group (p=.001).
Conclusion(s): Apart from possible deficits in balance (YBT-LQ anterior reach), the findings of this study suggest that throwing related shoulder pain in overhead athletes might not be related to overall lower limb balance, hip ROM and vertical or lateral jump performance. Influence of other kinetic chain segments or psychological factors could be of interest for future research.
Implications: Despite the focus on kinetic chain training in clinical practice, these findings suggest little impact of the proximal kinetic chain in overhead athletes with throwing related shoulder pain. Nevertheless, including the kinetic chain in rehabilitation could be relevant for functional training purposes.
Keywords: kinetic chain, upper extremity, lower body
Funding acknowledgements: The work was unfunded.
Purpose: To study if overhead athletes with throwing related shoulder pain would show differences in proximal chain (i.e. lower body) performance compared to a healthy matched control group.
Methods: The Y balance Test - Lower Quarter (YBT-LQ), vertical (VJ) and lateral jump (LJ) performance, and hip internal and external range of motion (ROM) were investigated in 31 overhead athletes with throwing related shoulder pain on the dominant side and 31 healthy matched controls. A linear mixed model was applied to determine significant differences in YBT-LQ, LJ and hip ROM test scores between groups (pain group or control group) and sides (dominant or non-dominant). An independent T-test was used to examine group differences in VJ performance.
Results: Results show no group or side differences for any of the included tests except for the YBT-LQ anterior reach: the control group reached significantly further than the pain group (p=.001).
Conclusion(s): Apart from possible deficits in balance (YBT-LQ anterior reach), the findings of this study suggest that throwing related shoulder pain in overhead athletes might not be related to overall lower limb balance, hip ROM and vertical or lateral jump performance. Influence of other kinetic chain segments or psychological factors could be of interest for future research.
Implications: Despite the focus on kinetic chain training in clinical practice, these findings suggest little impact of the proximal kinetic chain in overhead athletes with throwing related shoulder pain. Nevertheless, including the kinetic chain in rehabilitation could be relevant for functional training purposes.
Keywords: kinetic chain, upper extremity, lower body
Funding acknowledgements: The work was unfunded.
Topic: Musculoskeletal: upper limb; Sport & sports injuries
Ethics approval required: Yes
Institution: Ghent University
Ethics committee: Ethical Committee of Ghent University Hospital
Ethics number: B670201525329
All authors, affiliations and abstracts have been published as submitted.
