Muscular origins of the levator veli palatini muscle: Documenting anatomical variation and resolving five centuries of conflicting accounts

The levator veli palatini muscle (LVP) plays a fundamental and pivotal role in speech and swallowing. Despite centuries of anatomical description, the LVP origin remains a subject of debate, with several prominent sources offering contradictory findings. This study seeks to clarify conflicting accounts by conducting, to our knowledge, the largest dissection study on LVP morphology to date. We examined 27 temporal bone specimens and 27 hemi-heads from cadaveric donors. All exhibited an LVP origin from the portion of the cartilaginous Eustachian tube inside the osseous Eustachian tube orifice, with other anatomical variants including smaller accessory muscle bellies originating from a thick fibrous tissue layer overlying the petrous bone (the most common variant, 16/27) or from the carotid sheath (5/27). Our results did not support prior claims of the LVP originating exclusively from the petrous bone. There was no significant difference based on age or sex in the type of variant exhibited (p < 0.05). We also found that most temporal bones exhibited an infratubal spine of variable size and that, as corroborated by dissection and inter-observational documentation, these tended to function as attachments for a thick fibrous tissue layer that is continuous with both the carotid sheath and Weber-Liel fascia. These findings contribute to clinical applications such as postoperative monitoring of cleft palate repair patients among whom LVP growth is functionally important. They are also applicable to vocal tract reconstructions in extinct hominins where minor differences in relative LVP length could have functional impacts on speech and respiration by influencing velar biomechanics.