Article History
Received: 10 October 2018
Accepted: 25 November 2018
First Online: 30 November 2018
Compliance with ethical standards
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: On behalf of all authors, the corresponding author states that there is no conflict of interest. Disclosures outside of submitted work: ZB—consultancy: Xenco Medical, AO Spine; research support: SeaSpine (paid directly to institution); JCW—Royalties—Biomet, SeaSpine, Amedica, DePuy Synthes; Investments/Options—Fziomed, Promethean, Paradigm Spine, Benvenue, Nexgen, Vertiflex, Electrocore, Surgitech, Expanding Orthopedics, Osprey, Bone Biologics, Pearldiver; Board of Directors—North American Spine Society, North American Spine Foundation, AO Foundation, Cervical Spine Research Society; Fellowship Funding (paid to institution): AO Foundation.