The sphenoid bone
Sphenoid bone
The sphenoid bone is an unpaired bone of the neurocranium. It is situated in the middle of the skull towards the front, in front of the temporal bone and the basilar part of the occipital bone. The sphenoid bone is one of the seven bones that articulate to form the orbit. Its shape somewhat resembles that of a butterfly or bat with its wings extended.
Why can the sphenoid be called the keystone of the cranial floor?
Why can the sphenoid bone be called the keystone of the cranial floor? Since it is in contact with all of the other cranial bones. Cleft Palate variations of a type of clefting congenital deformity caused by abnormal facial development during gestation.
What is the sphenoid bone?
Separated by a bony septum projecting downward into the nasal cavity, the sphenoid bone also contains two sinuses, which lie side by side. The most common way for allopathic medical practitioners to access the sphenoid bone is through the nasal passages.
What are the greater and lesser wings of the sphenoid?
The greater wings of the sphenoid project laterally from the body and form the anterolateral floor of the cranium. The greater wings also form part of the lateral wall of the skull just anterior to the temporal bone and can be viewed externally. The lesser wings, which are smaller, form a ridge of bone anterior and superior to the greater wings.
What is a restricted sphenoid?
Associated with many common health problems, a restricted sphenoid can be freed by cranial-sacral therapy. Located in the very center of the skull, the sphenoid bone is in a unique and influential position.
Why can the sphenoid bone be called Keystone quizlet?
Why can the sphenoid bone be called the keystone of the cranial floor? Since it is in contact with all of the other cranial bones. variations of a type of clefting congenital deformity caused by abnormal facial development during gestation.
Why sphenoid bone is called the wasp bone?
Due to its shape, it is also referred to as the 'wasp bone'. It makes up most of the middle part of the base of the skull and contributes to the floor of the middle cranial fossa of the skull.
What is the sphenoid bone also called?
An unpaired bone located in the cranium (or skull), the sphenoid bone, also known as the “wasp bone,” is located in the middle and toward the front of the skull, just in front of the occipital bone.
Which bone is considered to be the keystone of the face?
The maxilla is the keystone of facial bones.
What makes the sphenoid bone different?
The sphenoid bone has articulations with twelve other paired and unpaired bones – this makes it the most complex bone in the human body. While the sphenoid bone is unpaired, it stretches from one side of the skull to the other.
Why is sphenoid bone unpaired?
The sphenoid bone is an unpaired bone of the neurocranium. It is situated in the middle of the skull towards the front, in front of the basilar part of the occipital bone. The sphenoid bone is one of the seven bones that articulate to form the orbit....Sphenoid boneTA2584FMA52736Anatomical terms of bone7 more rows
What is the bat shaped bone called?
Shaped like a butterfly or a bat, it has a central body and two lateral wings on either side. It is one of the bones that make up the orbit, in particular, forming the posterior surface. The articulations of the sphenoid are with the frontal, parietal, ethmoid, zygomatic, temporal, occipital, palatine, and vomer bones.
Is the sphenoid a irregular bone?
The irregular bones are: the vertebrC&, sacrum, coccyx, temporal, sphenoid, ethmoid, zygomatic, maxilla, mandible, palatine, inferior nasal concha, and hyoid.
What is the deepest bone in the skull?
The Ethmoid BoneThe Ethmoid Bone This is an unpaired skull bone that makes up one part of the orbit of the eye, separates the nasal cavity from the brain and is the bone located deepest within the head.
What is the keystone bone of the face and has large sinuses?
The sphenoid bone is a single, complex bone of the central skull (Figure 6.22). It serves as a “keystone” bone, because it joins with almost every other bone of the skull. The sphenoid forms much of the base of the central skull and also extends laterally to contribute to the sides of the skull (see Figure 6.18).
Which bone is considered to be the keystone of the cranium quizlet?
The sphenoid bone is considered to be the keystone of the cranium because it forms a central wedge that articulates with all other cranial bones.
Which landmark is not part of the sphenoid bone?
Identify the landmark that is not part of the sphenoid bone. The olfactory foramina are found in the cribriform plate of the ethmoid bone, not the sphenoid bone. Correct. The sella turcica is a depression in the central region of the sphenoid bone.
Why is the sphenoid bone called the keystone of the cranial floor?
Sphenoid bone is called the keystone of the cranial floor because it articulates with all the other cranial bones, holding them together. View the floor of the cranium superiorly (Figure 1) and note the sphenoid articulations.
Why is the sphenoid bone considered the keystone of the cranium?
The sphenoid bone is considered the keystone of the cranium because it forms a central wedge that articulates with every other cranial bone. It is a challenging bone to study because of its complex shape and orientation: Portions of the sphenoid are viewable from most aspects of the skull.
What is the foramen spinosum?
foramen spinosum. carotid groove . The sphenoid bone consists of a central body and three pairs of processes: the greater wings, lesser wings, and pterygoid processes (Figures 1 to 3). The superior surface of the sphenoid body bears a saddle-shaped prominence, the sella turcica (“Turkish saddle”).
What is the foramen ovale?
At the base of the lateral pterygoid process in the greater wing is the foramen ovale (= oval hole). The foramen lacerum (= lacerated), covered in part by a layer of fibrocartilage in living subjects, is bounded anteriorly by the sphenoid bone and medially by the sphenoid and occipital bones.
What is the horn of a saddle called?
The anterior part of the sella turcica, which forms the horn of the saddle, is a ridge called the tuberculum sellae. The seat of the saddle is a depression, the hypophyseal fossa, ...
What is the shape of a sphenoid?
The shape of the sphenoid resembles a butterfly with outstretched wings (Figures 1 and 2). The body of the sphenoid is the hollowed cubelike medial portion between the ethmoid and occipital bones. The space inside the body is the sphenoidal sinus, which drains into the nasal cavity (see Figure 3).
What is the lesser wing of the sphenoid?
The lesser wing of the sphenoid bone, or orbito-sphenoid, is a sharp, pointed triangular plate arising laterally from the upper anterior portion of the sphenoid body. The lesser wing features both superior and inferior surfaces: the superior surface is flattened and is in contact with the frontal lobe of the brain.
What is the sphenoid bone?
Named for its wedge-like butterfly shape, the sphenoid is a prominent, irregularly shaped bone at the base of the skull. Because it is in contact with all of the other cranial bones, the sphenoid is often referred to as the “keystone” of the cranial floor. The sphenoid has a number of features and projections, requiring a student to study it ...
Where is the sphenoid bone located?
Associated with many common health problems, a restricted sphenoid can be freed by cranial-sacral therapy. Located in the very center of the skull, the sphenoid bone is in a unique and influential position.
How many sinuses are in the sphenoid bone?
Separated by a bony septum projecting downward into the nasal cavity, the sphenoid bone also contains two sinuses, which lie side by side. The most common way for allopathic medical practitioners to access the sphenoid bone is through the nasal passages.
What bones are in the sphenoid?
The sphenoid articulates posteriorly with the occipital bone, laterally with the temporal and parietal bones, and anteriorly with the frontal and ethmoid bones. It consists of a hollow body, which contains the sphenoidal sinus, and three pairs of projections: The more superior lesser wings. The intermediate greater wings.
What are the problems associated with the sphenoid?
Problems Associated With the Sphenoid. Medical professionals often perceive the keystone of the cranial floor as off-balance or restricted in its movement. When the structure deep inside the skull is not moving freely, there can be many repercussions .
When did cranial sacral therapy become complementary medicine?
Since its official assimilation into complementary medicine in the 1970s, bodyworkers trained in cranial-sacral therapy have been able to create many healing opportunities by gently manipulating this cranial bone.
What is the superior surface of the sphenoid?
The superior surface of the body of the sphenoid contains a deep depression housing the pituitary gland, called the sella turcica, or Turk’s saddle. In addition, the plentitude of surfaces and articulations of the sphenoid harbor the passage of: The ophthalmic artery into the orbital cavity.
