Background: Scapular dyskinesis may cause not only rotator cuff (RC) tear but also weakness of the upper extremity, studies on scapular dyskinesis that may occur after RC repair is still lacking.
Objects: To determine whether scapular dsykinesis was present in patients after arthroscopic RC repair and to investigate the influence of passive scapular stabilization on upper extremity strength.
Methods: A total of 30 patients after RC repair participated in this study. To compare the scapula of the arthroscopic RC repair shoulder and the contralateral shoulder, the winged scapula (WS) was measured using a scapulometer and scapular dyskinesis was also classified by type. Fixed instruments for muscle strength measurements were used to measure upper extremity muscle strength differences depending on passive scapular stabilization position or natural scapular position. A chi-square test, an independent t-test and a 2-way mixed measures analysis of variance (ANOVA) was used as statistical analysis. In analyses, p < 0.05 was deemed to be statistically significant.
Results: Postoperative shoulder had a significant association with scapular dyskinesis and the WS compared to the contralateral shoulder (F = 0.052, p < 0.01). Postoperative shoulder, muscle strength in the shoulder abduction (p < 0.01), elbow flexion (p < 0.01) and forearm supination (p < 0.05) were significantly greater in the scapular stabilization position than in the scapular natural position.
Conclusion: Patients underwent arthroscopic RC repair had a significant association with scapular dyskinesis and muscle strength was improved by a passive scapular stabilization position, therefore scapular stabilization is important in rehabilitation program.

INTRODUCTION
MATERIALS AND METHODS
    1. Participants
    2. Measurement of the Winged Scapula
    3. Observational Clinical Assessment of ScapularDyskinesis
    4. Measurement of Isometric Upper Extremity MuscleStrength and Procedures
    5. Experimental Procedures
    6. Statistical Analysis
RESULTS
DISCUSSION
CONCLUSIONS
FUNDING
ACKNOWLEDGEMENTS
CONFLICTS OF INTEREST
AUTHOR CONTRIBUTION
ORCID
REFERENCES

• Won-jeong Jeong(Department of Rehabilitation Science, The Graduate School, Inje University)
• Duk-hyun An(Department of Physical Therapy, College of Healthcare Medical Science and Engineering, Inje University)
• Jae-seop Oh(Department of Physical Therapy, College of Healthcare Medical Science and Engineering, Inje University) Corresponding Author