Debate on the Morphological Variability of the Lateral Pterygoid Muscle-Discrepancies, Speculations and New Original Anatomical Samples.

The lateral pterygoid muscle (LPM), a critical component of the masticatory muscles, typically comprises upper (SLPM) and lower (ILPM) heads. However, it is essential to note that the LPM's structure is not a constant feature, as the number of bundles and their topography can vary. Moreover, additional heads, such as medial and middle heads, and unique-headed configurations of the LPM have been reported. Several studies have demonstrated the penniform structure of the LPM, which is further supported by its diverse pattern of innervation. Anatomically, the LPM originates from the greater wing and lateral pterygoid plate of the sphenoid bone, with variations in these origins being common. For instance, the presence of a broad lateral pterygoid plate or extensions from it can enlarge the origin area of the LPM. Equally variable are the insertions of the LPM, which can include attachments to the mandibular condyle and the temporomandibular joint disc. In some cases, aberrant LPM bundles may attach to the mandibular condyle outside the mandibular notch. Rarely encountered muscles like the pterygoideus proprius, pterygospinosus, and pterygofacialis further add to the diversity of this muscle. The anatomy of the LPM is subject to modification due to factors like atrophy or hypertrophy. Therefore, it is imperative to recognize that a one-size-fits-all anatomical pattern for the LPM does not exist. Instead, a personalized therapeutic approach should be based on a case-by-case determination of the LPM's specific anatomical configuration. This nuanced understanding challenges the simplistic view of the LPM and underscores the need for individualized clinical considerations.