Articles
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3,363 results found
Article
Obelion
The obelion refers to the skull landmark along the sagittal suture intersected by an imaginary line connecting the two parietal foramina, where both are present. It is said to represent the site of commencement of sagittal suture closure 1.
It is one of the skull landmarks, craniometric points ...
Article
Skull vault bones (mnemonic)
A useful mnemonic to remember the six skull vault bones is:
STEP OF 6
Mnemonic
S: sphenoid
T: temporal
E: ethmoid
P: parietal
O: occipital
F: frontal
6: number of skull bones
Article
Acetabular labrum
Acetabular labrum acts to deepen the acetabulum and increase contact between the pelvis and the femoral head. Its exact biomechanical role remains to be fully elucidated.
Gross anatomy
The acetabular labrum is a C-shaped fibrocartilaginous structure with an opening anteroinferiorly at the site...
Article
Dorello canal
Dorello canal channels the abducens nerve (CN VI) from the pontine cistern to the cavernous sinus.
Gross anatomy
Dorello canal is an interdural space (between the two layers of dura) found at the medial most end of the petrous ridge at the confluence of the inferior petrosal, basal, and caver...
Article
Sphenomandibular ligament
The sphenomandibular ligament is one of the two extrinsic ligaments of the mandible, the other being the stylomandibular ligament.
The sphenomandibular ligament descends from the spine of the sphenoid bone onto the medial surface of the mandibular ramus, attaching to the lingula. It is the prim...
Article
Extradural neural axis compartment
Extradural neural axis compartment (EDNAC) exists from the tip of the coccyx all the way to the back of the globe, and yet it is relatively unknown as a concept. It is bounded externally by the periosteum of the vertebrae and sacrum inferiorly and the skull superiorly, and the visceral (meningea...
Article
Os odontoideum
Os odontoideum (plural: ossa odontoidea) is an anatomic variant of the odontoid process of C2 and needs to be differentiated from persistent ossiculum terminale and from a type 2 odontoid fracture. It can be associated with atlantoaxial instability.
Although it was originally thought to be a c...
Article
Aortic arch
The aortic arch represents the direct continuation of the ascending aorta and represents a key area for a review of normal variant anatomy and a wide range of pathological processes that range from congenital anomalies to traumatic injury.
Summary
origin: continuation of the ascending aorta at...
Article
Accessory left atrial appendage
An accessory left atrial appendage is a frequent fortuitous finding in cardiac imaging, encountered in ~10% of patients. They are more often seen as a small diverticular structure projecting from the right upper side of the left atrial wall.
Differential diagnosis
it must not be confused with ...
Article
Lateral talocalcaneal angle
The lateral talocalcaneal angle is one of the angles that can be measured for the assessment of pes planus and pes cavus and assessment of hindfoot deformity.
Measurement
The lateral talocalcaneal angle is drawn on a weight-bearing lateral foot radiograph. There are two ways that it has been d...
Article
Internal oblique muscle
The internal oblique muscle is one of the muscles that form the anterior abdominal wall. Inferiorly, it contributes towards the formation of the inguinal ligament.
Summary
origin: originates along the whole length of the lumbar fascia, from the anterior two-thirds of the intermediate line of t...
Article
Transversus abdominis muscle
The transversus abdominis muscle, named according to the direction of its muscle fibers, is one of the flat muscles that form the anterior abdominal wall. It is deep to the internal oblique muscle and ends in the anterior aponeurosis, which ultimately blends with the linea alba.
Summary
origi...
Article
External oblique muscle
The external oblique muscle is one of the muscles that forms the anterior abdominal wall. Its free inferior border forms the inguinal ligament, and its aponeurotic part contributes to the anterior wall of the inguinal canal.
Summary
origin: outer surface of the shaft of the lower eight ribs 3...
Article
Focal fatty deposits in bone marrow
Focal fatty deposits, also known as marrow islands or replacements in the bone marrow, are well-defined focal fat islands within the bone marrow of the spine or other parts of the axial skeleton 1,2.
Epidemiology
Common in older individuals, related to age but not to sex.
Associations
Focal ...
Article
External ear
The external ear (or outer ear) comprises the auricle (or pinna), the external auditory meatus, and the tympanic membrane ("eardrum"). The auricle concentrates and amplifies sound waves and funnels them through the outer acoustic pore into the external auditory meatus to the tympanic membrane.
...
Article
Superior vermian vein
The superior vermian vein is formed in the midline over the superior aspect of the cerebellar vermis (over the anterior lobe) by multiple tributaries draining not just the subjacent vermis but also the adjacent cerebellar hemispheres. These tributaries most often coalesce into a single trunk ove...
Article
Facial nerve
The facial nerve is the seventh (CN VII) cranial nerve and comprises two roots, a motor root and a smaller mixed sensory, taste and parasympathetic root, known as nervus intermedius, which join together within the temporal bone (TA: nervus facialis or nervus cranialis VII).
The facial nerve has...
Article
Canalis basilaris medianus
The canalis basilaris medianus (median basal canal), also known as clival canal, median clival canal, or inferior median clival canal, refers to a number of anatomic variant midline canals in the clivus, typically involving the basioccipital portion.
Gross anatomy
These canals are generally we...
Article
Modiolus (mouth)
The modiolus (plural: modioli), also known as the modiolus anguli oris or commissural modiolus, is a small fibromuscular structure at the corner of the mouth where fibers from multiple facial muscles converge, and helps coordinate the action of these muscles.
Gross anatomy
The convergence of t...
Article
Myocardium
The myocardium defines the middle layer of the cardiac wall between the endocardium and the pericardium and forms the muscular part of the heart.
Gross anatomy
The myocardium represents the middle layer of the cardiac wall. It is located between the endocardium and the epicardial layer of the ...