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Updated: Jul 14, 2026
Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
Exploratory anchor-derived six-month improvement thresholds for sleep quality and pain after reverse total shoulder
Fahri Erdi Malkoç1, Muhammed Yusuf Afacan1,2, Okan Can Karadeniz1
1Department of Orthopaedics and Traumatology, Istanbul Physical Therapy and Rehabilitation Training and Research Hospital, Istanbul, Turkiye.
Background:
Sleep disturbance is a common patient-reported problem in patients undergoing reverse total shoulder arthroplasty (rTSA). However, clinically interpretable improvement thresholds for sleep quality after rTSA remain unclear. This study aimed to derive exploratory anchor-based 6-month improvement thresholds for sleep quality, assessed using the Pittsburgh Sleep Quality Index (PSQI), and pain, assessed using the visual analog scale (VAS), after rTSA.
Methods:
Sixty-one patients undergoing primary rTSA with complete pre-operative and 6-month post-operative PSQI, VAS, and global rating of change (GRC) data were retrospectively analyzed. Exploratory receiver-operating characteristic (ROC) curve analyses were performed using the GRC anchor, and Youden-derived thresholds were calculated. Anchor validity was assessed using Spearman correlation analysis between ordinal GRC responses and changes in PSQI and VAS.
Results:
rTSA was associated with significant 6-month improvements in both PSQI and VAS scores (both P < .001). Based on the GRC anchor, 54 patients were classified as improved and 7 as not improved, indicating marked imbalance between groups. The GRC anchor demonstrated a weak, nonsignificant association with PSQI change and a moderate association with VAS change. Exploratory ROC analysis yielded approximate improvement thresholds of 7 points for PSQI and 4 points for VAS pain.
Conclusion:
rTSA was associated with substantial 6-month improvements in sleep quality and pain. In this small retrospective cohort, exploratory anchor-based ROC analyses generated preliminary improvement thresholds of approximately 7 points for PSQI and 4 points for VAS pain. However, the weak PSQI anchor correlation, severe imbalance in anchor-defined groups, and modest ROC discrimination indicate that these estimates should be considered hypothesis-generating rather than definitive Minimal Clinically Important Difference values.