ISAKOS: 2019 Congress in Cancun, Mexico

2019 ISAKOS Biennial Congress ePoster #2040


Use of the Western Ontario Rotator Cuff (WORC) Index in a Normal United States Population

Sarah Kemp, BA, Minneapolis, MN UNITED STATES
Christopher Urband, MD, San Diego, CA UNITED STATES
Lucas Haase, BA, Minneapolis, MN UNITED STATES
Michael Obermeier, BA, Minneapolis, MN UNITED STATES
Robby Sikka, MD, Bloomington, MN UNITED STATES
Marc Tompkins, MD, Minneapolis, MN UNITED STATES

Tria, Bloomington, MN, UNITED STATES

FDA Status Not Applicable


The WORC survey was administered to a normal US population to develop a normative data set and identify risk factors for poor scores.



Most studies on the Western Ontario Rotator Cuff (WORC) Index have focused on populations with shoulder pathology, but there is limited data on WORC scores in a population without shoulder pathology.
Hypothesis/Purpose: Primary: Generate normative reference values for the WORC in an adult epidemiological sample. Secondary: Identify demographic factors and co-morbidities that may impact WORC scores.


The WORC survey was completed by patients and family members at a suburban outpatient orthopedic center. Patients with current shoulder injury or former upper extremity surgery were excluded. Percentage scores were calculated for total and subscale measures. Demographic factors and co-morbidities were evaluated to identify possible risk factors for a lower baseline score.


There were 988 participants (434 men, 554 women). Overall WORC mean was 93.76 ± 12.54. Each subscale was greater than 90 for all sex- and age-based subgroups. Average WORC scores were greater than those reported in previous literature following surgery for shoulder pathology. Demographic risk factors for poor WORC scores included BMI greater than 30 (p<0.05), tobacco use (p<0.05), a history of shoulder problems (p<0.001), and a history of shoulder injections (p<0.05).


This study provides baseline values for the WORC survey in a United States suburban population across a range of age groups, demonstrating that surgery for shoulder pathology often results in improved WORC scores, but may not return patients to baseline. Demographic risk factors for lower scores include smoking, BMI above 30, history of shoulder problems, or history of shoulder injection.