Patient-Reported Outcome Measures Show No Relevant Change Between 1-Year and 2-Year Follow-Up After Treatment for Anterior Shoulder Instability: A Systematic Review.

Purpose: To compare patient-reported outcome measures (PROMs) at 1-year and 2-year follow-up after treatment for anterior shoulder instability.

Methods: Randomized controlled trials and prospective studies that evaluated and reported PROMs after a capsulolabral repair (with or without remplissage), bone augmentation, or nonoperative treatment to treat anterior shoulder instability at both 1-year and 2-year follow-up were included. PROMs were compared between 1-year and 2-year follow-up; forest plots with mean difference were created to compare baseline, 1-year, and 2-year follow-up; and scatterplots were created to visualize clinical improvement over time.

Results: Fourteen studies, comprising 923 patients, with levels of evidence Level I and II were included. Nine PROMs, of which predominantly were the Western Ontario Shoulder Instability Index (WOSI; 11 studies; 79%), were evaluated. Minimal to no statistically significant change in WOSI, Oxford Shoulder Instability Score, American Shoulder and Elbow Surgeons (ASES), Subjective Shoulder Value, Simple Shoulder Test, Disabilities of Arm, Shoulder, and Hand (DASH), Quick DASH, Single Assessment Numeric Evaluation, or visual analog scale was observed between 1-year and 2-year follow-up. Pooling of the WOSI, Oxford Shoulder Instability Score, ASES, and Single Assessment Numeric Evaluation demonstrated improvement from baseline to 1-year follow-up and minimal to no change between 1-year and 2-year follow-up. Scatterplots of the WOSI and ASES demonstrated the most improvement within 6 months and no clear improvement after 1-year follow-up. Recurrence rates increased with time but varied between studies.

Conclusions: In contrast to recurrence rates, which have been shown to increase with time, minimal to no statistically significant change was observed for any of the included PROMs between 1-year and 2-year follow-up. This finding raises the question as to whether it is necessary to evaluate PROMs in long-term follow-up of patients after shoulder stabilization treatment.

Level of evidence: Level II, systematic review of Level I and II studies.