Anatomy of the lateral pterygoid muscle and its relationship with temporomandibular disorders. A literature review

The lateral pterygoid muscle is a chewing muscle that is found bilaterally in the cranial region. Anatomically, the lateral pterygoid muscle is made up of two bellies, an upper belly and a lower belly. Its anatomical description present in the scientific literature showed that there is an anatomical difference or variation, mainly the insertions of the upper belly of the lateral pterygoid muscle at the level of the temporomandibular joint, and specifically in the disc and articular condyle, although distributions are reported similarly. They are not entirely accurate in smaller quantities: some articles reported variations in the insertion of the lower belly and others the appearance of a third belly of the lateral pterygoid muscle or medial belly. As mentioned above, a high number of studies that presented some type of lateral pterygoid muscle variation was associated with some type of temporomandibular disorders of the joint or some of its intra or extra-articular components. A review of the literature in scientific databases was carried out after the selection of the scientific articles, which were analyzed in full text, and the relationship between the anatomy of the lateral pterygoid muscle and the temporomandibular disorders was sought.