Background: The nerve conduit is a generally accepted tool to facilitate the repair of short nerve gaps. Limitations in effectiveness have been recognized, and a steady stream of possible conduit improvements has been published in the scientific literature. Analysis of this information, particularly when small animal models have been utilized, seems to indicate that nearly any modification of a nerve conduit improves outcomes in repairs of short gaps over standard nerve conduits. This seems statistically and biologically improbable and suggests a bias in the literature. Methods: A standardized systemic review of the scientific literature on rodent model studies assessing conduit modifications was undertaken to determine the incidence of positive or supportive outcomes. Results: Modifications were deemed superior in 97.3% of studies when compared with unmodified conduits and deemed equivalent or superior in 52.1% of studies when compared with autograft. Conclusions: A seemingly disproportionate number of positive results suggest that the literature on nerve conduit modifications may be skewed. We believe that there is a publication bias in the literature, and this warrants further investigation.
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