Authors’ Response:
We thank the authors of the letter for their interest in our manuscript, “Fixed- Versus Adjustable-Loop Femoral Cortical Suspension Devices for Anterior Cruciate Ligament Reconstruction: A Systematic Review and Meta-analysis of Biomechanical Studies.”3 We appreciate the opportunity to respond to their concerns.
First, we performed our systematic review using the PubMed, EMBASE, and Cochrane Library databases, which is a recommended combination of databases for performing systematic reviews.7 The study by Chang et al1 was published online ahead of print on November 13, 2017, and therefore was included in our search up to November 20, 2017. The other 2 articles2,6 published in 2018 and mentioned in the letter were not published online before our search date. The articles by Kamelger et al4 and Noonan et al5 were not included in our systematic review, as their biomechanical testing protocols differed substantially from the included studies.
As mentioned in the Discussion section of our article, we recognize that the high level of heterogeneity of this meta-analysis (based on specimen type, fixation devices, and biomechanical testing protocols) is a significant limitation of this study. Additionally, we acknowledge the limitation of not distinguishing the results based on isolated device versus specimen testing setup. Results were combined in order to net a larger sample size for analysis. Although this factor limits the conclusions that can be drawn from this study, the results of this study provide insight into the advantages and disadvantages of these different devices and prompt further clinical studies on this topic.
Darby A. Houck, BA
Matthew J. Kraeutler, MD
Eric C. McCarty, MD
Jonathan T. Bravman, MD
Aurora, Colorado, USA
Paterson, New Jersey, USA
Footnotes
One or more of the authors has declared the following potential conflict of interest or source of funding: E.C.M. receives royalties from Biomet and Elsevier, is a consultant for Biomet and DePuy, and receives research support from Biomet, Mitek, Smith & Nephew, and Stryker. J.T.B. is a consultant for DJ Orthopaedics, Shukla Medical, Encore Medical, and Smith & Nephew; receives royalties from Shukla Medical; receives research support from Stryker; has received hospitality payments from Encore Medical and Smith & Nephew; and has received fellowship funding from Smith & Nephew, Mitek, and Stryker. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.
References
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