Evaluating glenohumeral osteoarthritis: The relative impact of patient age, activity level, symptoms, and Kellgren-Lawrence grade on treatment

Background: It is not always clear how to treat glenohumeral osteoarthritis, particularly in young patients. The goals of this study were to 1) quantify how patient age, activity level, symptoms, and radiographic findings impact the decision-making of shoulder specialists and 2) evaluate the observer reliability of the Kellgren-Lawrence (KL) grading system for primary osteoarthritis of the shoulder. Methods: Twenty-six shoulder surgeons were each sent 54 simulated patient cases. Each patient had a different combination of age, symptoms, activity level, and radiographs. Responders graded the radiographs and chose a treatment (non-operative, arthroscopy, hemiarthroplasty, or total shoulder arthroplasty). Spearman correlations and chi square tests were used to assess the relationship between factors and treatments. Sub-analysis was performed on surgical cases. An intra-class correlation (ICC) was used to assess observer agreement. Results: The significant correlations (P<0.01) were: symptoms [0.46], KL grade [0.44], and age [0.11]. In the sub-analysis of operative cases, the significant correlations were: KL grade [0.64], age [0.39], and activity level [-0.10]. The chi square analysis was significant (P<0.01) for all factors, but the practical significance of activity level was minimal. The ICCs were [inter](intra): KL [0.79] (0.84), patient management [0.54]. Conclusion: When evaluating glenohumeral osteoarthritis, patient symptoms and KL grade are the factors most strongly associated with treatment. In operative cases, the factors most strongly associated with the choice of operation were the patient's KL grade and age. Additionally, the KL classification demonstrated excellent observer reliability. However, there was only moderate agreement among shoulder specialists regarding treatment, indicating that this remains a controversial topic.