Foramen spinosum

The foramen spinosum is a small foramen in the greater wing of the sphenoid bone of the skull. It connects the middle cranial fossa (superiorly), and infratemporal fossa (inferiorly).'''''' Contents The foramen transmits the middle meningeal artery and vein, It may be incomplete, which may occur in almost half of the population. Conversely, in a minority of cases (less than 1%), it may also be duplicated, particularly when the middle meningeal artery is also duplicated. The foramen may pass through the sphenoid bone at the apex of the spinous process, or along its medial surface. The average diameter of the foramen spinosum is 2.63 mm in adults. It is usually between 3 and 4 mm away from the foramen ovale in adults. The earliest perfect ring-shaped formation of the foramen spinosum was observed in the eighth month after birth and the latest seven years after birth in a developmental study of the foramen rotundum, foramen ovale and foramen spinosum. The majority of the foramina in the skull studies were round in shape. Animals In other great apes, the foramen spinosum is found not in the sphenoid, but in parts of the temporal bone such as the squamous part, found at the sphenosquamosal suture, or absent. == Function ==

The foramen spinosum permits the passage of the middle meningeal artery, middle meningeal vein, and the meningeal branch of the mandibular nerve. == Clinical significance ==

Due to its distinctive position, the foramen is used as an anatomical landmark during neurosurgery. As a landmark, the foramen spinosum reveals the positions of other cranial foramina, the mandibular nerve and trigeminal ganglion, foramen ovale, and foramen rotundum. It may also be relevant in achieving haemostasis during surgery, This may be useful in trauma surgery to reduce bleeding into the neurocranium, or for removal of the pyramidal process of the palatine bone. == History ==

The foramen spinosum was first described by the Danish anatomist Jakob Benignus Winslow in the 18th century. It is so-named because of its relationship to the spinous process of the greater wing of the sphenoid bone. However, due to incorrectly declining the noun, the literal meaning is "hole full of thorns" (). The correct, but unused name would, in fact, be ''''. == See also ==