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Bias in cervical total disc replacement trials

  • Motion Preserving Spine Surgery (C Kepler, section editor)
  • Published:
Current Reviews in Musculoskeletal Medicine Aims and scope Submit manuscript

Abstract

Purpose of review

Cervical disc replacement (CDR) has emerged as a motion-preserving alternative to anterior cervical discectomy and fusion in selected cases. Despite favorable literature, CDR is not universally accepted because of concerns regarding bias in the existing literature. The purpose of this review is to identify the possible biases in the disc replacement literature.

Recent findings

Recent studies that compare CDR and ACDF have demonstrated equivalent or superior outcomes, lower rates of secondary surgery, and equivalent safety at medium- and long-term follow-up. In our review, we identified four types of bias that may affect the CDR literature: publication bias, external validity, confounding bias, and financial conflicts of interest.

Summary

Bias, whether intentional or unintentional, can impact the interpretation and outcome of CDR studies. Recognition of this issue is critical when utilizing the existing literature to determine the efficacy of CDR and designing future studies.

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Papers of particular interest, published recently, have been highlighted as: • Of importance

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Author information

Authors and Affiliations

  1. Department of Orthopedic Surgery, Department of Neurological Surgery, Rothman Institute, Thomas Jefferson University, 2500 English Creek Ave, Egg Harbor, NJ, 08234, USA

    Kristen Radcliff & Barrett Woods

  2. Robert Wood Johnson Medical School, Rutgers University, Brunswick, NJ, USA

    Sean Siburn

  3. Rothman Institute, Bryn Mawr, PA, USA

    Hamadi Murphy

  4. Department of Orthopedic Surgery, Carl Icahn School of Medicine, Mt. Sinai University, New York, NY, USA

    Sheeraz Qureshi

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  1. Kristen Radcliff
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  2. Sean Siburn
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  3. Hamadi Murphy
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  4. Barrett Woods
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  5. Sheeraz Qureshi
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Corresponding author

Correspondence to Kristen Radcliff.

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Conflict of interest

Kris Radcliff reports personal fees from Globus Medical, personal fees from DePuy, personal fees from Stryker, personal fees from Medtronic, personal fees from Orthopedic Sciences, Inc., personal fees from NuVasive, personal fees from 4 Web Medical, other from LDR Medical (now Zimmer), outside the submitted work, and shareholder status at Rothman Institute.

Sheeraz Qureshi is a board or committee member for the following organizations: AAOS, Cervical Spine Research Society, Musculoskeletal Transplant Foundation, and NASS. He is on the editorial or governing boards of the following organizations: Clinical Orthopaedics and Related Research, Contemporary Spine Surgery, Global Spine Journal, Spine, and Spine Journal. Dr. Qureshi has also received speaking/consultancy fees from the following organizations: Globus Medical, Medtronic, Medtronic Sofamor Danek, Orthofix, Inc., Stryker, and Zimmer.

All other authors declare no conflict of interest.

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This article does not contain any studies with human or animal subjects performed by any of the authors.

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This article is part of the Topical Collection on Motion Preserving Spine Surgery

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Radcliff, K., Siburn, S., Murphy, H. et al. Bias in cervical total disc replacement trials. Curr Rev Musculoskelet Med 10, 170–176 (2017). https://doi.org/10.1007/s12178-017-9399-2

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