Current evidence on the neurosurgical impact of chin to chest positioning

Chin-to-chest positioning is a position often maintained after tracheal resection to reduce tension in the surgical area. However, there has not been a comprehensive effort to systematically synthesize and categorize the available data on chin-to-chest deformity and extreme cervical flexion. This study provides a scoping review of the relevant literature on the neurosurgical implications of this positioning. We conducted a scoping review to assess the impact of chin-to-chest positioning on neurosurgical outcomes on November 4, 2024. Studies were accessed through both Scopus (search term: TITLE-ABS-KEY (“chin to chest” OR “flexion positioning”), which yielded 64 results and PubMed (search term: “chin to chest” OR “flexion positioning”), which yielded 50 results. Our inclusion criteria included all studies that analyzed neurosurgical outcomes after chin-to-chest positioning, yielding nine independent articles, which were all spinal cord-related. Following screening against the predefined eligibility criteria, all nine studies were deemed eligible and were included in the review. Nine articles discussing post-chin-to-chest neurosurgical outcomes included nine spine studies. Only one study was published in the last three years, while the oldest was published in 2010. Seven studies were case reports, which were spine-related neurosurgical outcomes. Studies did not provide a consensus on preventing undesirable neurosurgical outcomes. Some of the adverse neurosurgical outcomes discussed, all of which came from case reports, were cervical myelopathy, acute dystonia, spastic quadriparesis, motor complete tetraplegia, hyperreflexia, paraplegia, among others. This scoping review highlights a wide range of neurosurgical adverse outcomes associated with prolonged chin-to-chest positioning. The reported neurosurgical injuries raise concerns regarding this practice although further investigation is needed to better characterize the associated risks.