The Continuous Fragility Index of Outcomes in Rotator Cuff Repair Augmentation Randomized Trials: A Systematic Review

James Abesteh; Mohammed Al-Asadi; Hassaan Abdel Khalik; Danielle Dagher; Kim Madden; Asheesh Bedi; Moin Khan

doi:10.1016/j.jse.2024.11.003

The Continuous Fragility Index of Outcomes in Rotator Cuff Repair Augmentation Randomized Trials: A Systematic Review

J Shoulder Elbow Surg. 2024 Dec 30:S1058-2746(24)00959-5. doi: 10.1016/j.jse.2024.11.003. Online ahead of print.

Authors

James Abesteh¹, Mohammed Al-Asadi², Hassaan Abdel Khalik³, Danielle Dagher⁴, Kim Madden⁴, Asheesh Bedi⁵, Moin Khan⁶

Affiliations

¹ Michael G. DeGroote School of Medicine, McMaster University, Hamilton, ON, Canada.
² Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
³ Division of Orthopaedics, Department of Surgery, McMaster University, Hamilton, ON, Canada.
⁴ Division of Orthopaedics, Department of Surgery, McMaster University, Hamilton, ON, Canada; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada.
⁵ Northshore Orthopedics, Chicago, IL, USA.
⁶ Division of Orthopaedics, Department of Surgery, McMaster University, Hamilton, ON, Canada; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada. Electronic address: khanmm2@mcmaster.ca.

PMID: 39742947
DOI: 10.1016/j.jse.2024.11.003

Abstract

Background: Symptomatic rotator cuff tears often undergo surgical repair, which may be paired with various augmentation strategies to enhance structural healing rates. While many randomized controlled trials (RCTs) evaluate augmentation techniques, the statistical robustness of many findings in these studies is unknown. This systematic review aims to evaluate the continuous fragility index (CFI) of RCTs on augmentation techniques for rotator cuff repairs.

Methods: MEDLINE, Embase, and CENTRAL databases were comprehensively searched from inception to September 2023 for RCTs assessing the efficacy of at least one augmentation strategy during rotator cuff repair. Eligible studies reported at least one statistically significant finding for a continuous outcome. The CFI for eligible outcomes was calculated, with median CFI presented by type of augmentation and outcome. Multivariable regression was performed to identify associations between CFI and other outcome variables.

Results: Nineteen RCTs (1417 patients) were included in the final analysis. The median CFI for the 86 outcomes analyzed was 5.85 (IQR 2.3 - 14.4). Augmentation-specific analysis demonstrated variability in CFIs, with the most robust outcomes found in platelet-rich plasma studies (median 10.95, IQR 3.3 - 19.0) and suture-spanning augmentation studies (median 11.90, IQR 11.45 - 14.35). Outcome-specific analysis demonstrated range of motion outcomes as most robust (median 9.85, IQR 7.58 - 14.0) and strength-related outcomes as most fragile (median 2.00, IQR 1.0 - 16.3). Multivariable regression identified larger sample size as a statistically significant predictor of greater CFI. Notably, loss to follow-up exceeded the CFI in 31.4% of outcomes.

Conclusion: The observed median CFI of 5.85 in augmentation trials is consistent with the CFI reported in orthopedic and sports medicine literature. However, almost a third of outcomes had a loss to follow-up exceeding their CFI, risking the reversal of study findings with more robust follow-up and outcomes. Clinicians and researchers should consider fragility in addition to p-values when assessing study results, especially in the context of high loss to follow-up. Future trials should report the fragility of their findings.

Level of evidence: Systematic Review; Research Methodology Study.

Keywords: Rotator cuff tear; continuous fragility index; fragility index; platelet-rich plasma; rotator cuff repair; rotator cuff repair augmentation.

Publication types

Review