Background and aim
There is a growing body of evidence, that central pain processing (CPP) and psychosocial factors may maintain or drive shoulder pain. In patients undergoing rotator cuff repair (RCR,) findings report that patients’ expectations may predict outcome after surgery 1. Yet, there is a lack of evidence on modifiable factors that potentially moderate the outcome after RCR. 
The aim refers to identify such moderators for outcome after RCR. 
Methods
The longitudinal study will investigate 141 datasets of adult patients undergoing RCR at Kantonsspital Winterthur, Switzerland. Mean change of three measurement points, 1. pre-operative, 2. 12 weeks post-operative, 3. 12 months post-operative of primary (Western Ontario Rotator Cuff Index (WORC)) and secondary outcome measures (Constant – Score, maximum pain and quality of life) will be analysed by mixed-effects regression model for repeated measures. Stepwise inclusion of the 6 potential moderators will be conducted using linear and logistic regression models. Potential moderators are obtained by quantitative sensory testing and central sensitisation inventory (CPP), pain catastrophizing scale, illness perception questionnaire, perceived stress scale and questions about expectations and sleep.
Results
Assessments started in September 2018. Preliminary results from the pilot study will be available in summer 2019 and may provide insight in short-term prognosis for  outcome 12 weeks postoperative. 
Conclusion
Results may disclose moderators for outcome after RCR and foster a more patient-centred treatment approach with the aim to tailor the course of care towards a beneficial outcome. 
Funding acknowledgement
Acknowledgments refer to the staff of Kantonsspital Winterthur. Ethical approval ID: 2018-02089.

POTENTIAL MODERATORS FOR OUTCOME AFTER ROTATOR CUFF REPAIR: A PILOT STUDY