Increased Use of Total Shoulder Arthroplasty and Improved Patient-reported Outcome for Osteoarthritic Patient in Denmark From 2006 to 2015: A Nationwide Cohort Study From the Danish Shoulder Arthroplasty Registry

To investigate the use of different arthroplasty types for osteoarthritis in Denmark from 2006-2015, to report the patient-reported outcome, and to study if changes in the use of arthroplasty types have changed the outcome from 2006-2015. Because of limited information from randomized trials and large observational studies, data from the Danish Shoulder Athroplasty Registry has been an important source of information regarding patient-reported outcome of different arthroplasty types. We included 2,867 shoulder arthroplasties performed for osteoarthritis between 2006-2015 and reported to the Danish Shoulder Arthroplasty Registry. The Western Ontario Osteoarthritis of the Shoulder (WOOS) index at one year was used as patient-reported outcome. The raw score was converted to a percentage of a maximum score. General linear models were used to analyze differences in WOOS. The proportion of anatomical total shoulder arthroplasty and reverse shoulder arthroplasty increased from 3% and 7% in 2006 to 53% and 27% in 2015. The mean WOOS score was 70 (SD26) after resurfacing hemiarthroplasties (n=1.258), 68 (SD26) after stemmed hemiarthroplasty (n=500), 82 (SD23) after anatomical total shoulder arthroplasties (n=815) and 74 (SD23) after reverse shoulder arthroplasties (n=213). The overall WOOS increased with 18 (95%CI12:22,P<0.001) in the univariate model and 10 (95%CI5:15,P<0.001) in the multiple model. We found improved WOOS scores for anatomical total shoulder arthroplasty (14,95%CI:5-23,P=0.003) from 2006-2015. We found an increased WOOS from 2006-2015 which was primarily related to a higher proportion of anatomical total shoulder arthroplasty and reverse shoulder arthroplasty towards the end of the studied period, and to improved outcome of anatomical total shoulder arthroplasty.