RT Journal Article SR Electronic T1 087 Evaluation of sport specific adaptations at the shoulder joint and core endurance among elite female volleyball players with and without overuse related shoulder problems JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP A36 OP A36 DO 10.1136/bjsports-2021-IOC.83 VO 55 IS Suppl 1 A1 Bucher, Lydia A1 Pfister, Pierrette Baschung A1 Cools, Ann YR 2021 UL http://bjsm.bmj.com/content/55/Suppl_1/A36.2.abstract AB Background Yet published values outlining the differences of sport-specific adaptations at the shoulder joint between symptomatic (S) and non-symptomatic (nS) overhead athletes vary widely. Information defining the link between overuse injuries in relation to both shoulder joint and core endurance is also lacking.Objective To evaluate if sport-specific adaptations at the shoulder joint are greater in volleyball players with shoulder problems and core stability would be associated with sport-specific adaptations at the shoulder.Design Cross-sectional study.Setting This study was performed during the indoor volleyball season 2017/2018 in coordination with the Swiss Volleyball Federation.Patients (or Participants) 60 female volleyball players with and without overuse shoulder problems playing in a National League volleyball team.Interventions (or Assessment of Risk Factors) Standardized clinical field tests for passive shoulder ROM in IR and ER, isometric strength of shoulder IR and ER, scapular dyskinesis test and core endurance test were performed during a test session of 1 h. The assessor was blinded to information on the players’ current shoulder status.Main Outcome Measurements Side, group and subgroup comparisons of ROM, strength, scapular control and core endurance and correlations between core endurance and ER strength deficit, strength ratio ER/IR and scapular dyskinesis were described.Results All players showed significant adaptations in ROM, strength and scapular control of their dominant shoulder (Ds). Players in the S subgroup had significantly weaker IR strength than nS players (mean difference, 7 N; 95% CI, 0.54 to 13.05; P ≤ .034; r = 0.295) and tended to have ER strength deficit. Furthermore, the lower the ER strength deficit, the better the core endurance in the side plank position (Ds: r = 0.30; 95% CI, 0.11 to 0.53; P ≤ .035).Conclusions Elite female volleyball players showed typical sport-specific adaptations in their dominant shoulder. Values of adaptations did only differ in strength and only between subgroups. Further studies need to quantify the association between core endurance and shoulder strength.