Sphenomandibular ligament and degenerating Meckel's cartilage revisited: Sequential variations with temporal bone deformity for ligament attachment in near-term human fetuses.
J Anat
; 244(3): 514-526, 2024 03.
Article
en En
| MEDLINE
| ID: mdl-37988318
ABSTRACT
BACKGROUND:
The sphenomandibular ligament (SML) is considered to originate from Meckel's cartilage (MC). However, no study has examined how the os goniale contributes to SML development.METHODS:
Semiserial histological sections of heads from 18 near-term fetuses at 27-40 weeks of gestation were examined. OBSERVATIONS The os goniale and the anterior process of the malleus (AP) provided a long, bar-like membranous bone complex that passed through the petrotympanic and tympanosquamosal fissures. Notably, the AP-goniale complex is sometimes elongated inferiorly to join the SML (n = 4 specimens). Along the complex in the bone fissures, a degenerating MC was often present (n = 12). With (n = 6) or without (n = 3) the MC remnant, the tympanic bone (TYB) protruded inferomedially near the tympanosquamosal fissure, and it sometimes continued to a cartilaginous SML (n = 3). The temporal bone squamosa or petrosa provided a similar bony process approaching the SML. The middle meningeal artery often ran between the sphenoid and petrosa.CONCLUSIONS:
Most of the specimens (n = 15) exhibited a sequential change from a cartilaginous SML as a continuation of the MC remnant to the ligament after the disappearance of the cartilage. The degenerating MC appeared to cause transformation from the AP-goniale complex and/or TYB to "another ligament" that replaced the usual SML at the upper part. Near the MC remnant, a similar transformation was also suggested on the squamosa or petrosa. The sphenoid spine appeared to originate often from the sphenoid ala major but sometimes from the TYB.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Articulación Temporomandibular
/
Ligamentos Articulares
Límite:
Humans
Idioma:
En
Revista:
J Anat
Año:
2024
Tipo del documento:
Article
País de afiliación:
China