Hyoid Bone Position and Upper Airway Morphology of Children With Obstructive Sleep Apnea: A Systematic Review and Meta-analysis.

The objective of this systematic review was to summarise the existing evidence regarding hyoid bone position and upper airway morphology of children with obstructive sleep apnea (OSA). Electronic searches were carried out in PubMed, Embase, Web of Science, CINAHL and WorldCat databases without any restrictions on language from inception to March 2024. The studies which compared the hyoid bone position and upper airway morphology using lateral cephalograms between children with and without OSA will be included. The methodological quality of the included studies was assessed using Newcastle-Ottawa Scale, and the meta-analysis was conducted utilising random-effects model. Twelve cross-sectional studies and one case-control study were included. One study was rated as low quality, three as medium quality, five as high quality, and four as very high quality. Meta-analysis showed that compared to healthy children, children with OSA tended to have increased distance between hyoid bone and mandibular plane (Hy-MP, MD: 3.33, 95% CI: 1.90 to 4.77, p < 0.00001, I² = 72%), increased distance between hyoid bone and cervical vertebra (Hy-C3, MD: 1.54, 95% CI: 0.62 to 2.46, p = 0.001, I² = 68%), and a smaller airway space behind the soft palate (U-MPW, MD: -3.07, 95% CI: -4.76 to -1.38, p = 0.0004, I² = 68%). Whereas there was no significant difference in inferior posterior airway space between children with OSA and healthy controls (IPAS, MD: -1.51, 95% CI: -3.37 to 0.35, p = 0.11, I² = 71%). In children with OSA, the hyoid bone may exhibit a more anterior and inferior position and the airway posterior to the soft palate demonstrated a narrower dimension. Registration: PROSPERO (CRD42024528171).