Articles
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1,091 results found
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
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
Cervical rib
Cervical ribs are supernumerary or accessory ribs arising from the seventh cervical vertebra. They occur in ~0.5% of the population, are usually bilateral, but often asymmetric 2, and are more common in females.
Related pathology
Although cervical ribs are usually asymptomatic, they are the mo...
Article
Wrist
The wrist is a complex synovial joint formed by articulations of the radius, the articular disc of the distal radioulnar joint and the carpal bones.
Terminology
Somewhat confusingly, the term carpus can be used as a synonym for the wrist joint as a whole, or in a more restricted sense to refer...
Article
Fibularis longus muscle
The fibularis longus muscle (also known as peroneus longus muscle) is one of the muscles of the lateral compartment of the leg.
Summary
origin: head of the fibula
insertion: first metatarsal and medial cuneiform
innervation: superficial peroneal nerve (superficial fibular nerve)
action: foo...
Article
Lesions of the prepatellar quadriceps continuation
Lesions of the prepatellar quadriceps continuation are partial or complete tears of the prepatellar quadriceps continuation, that can occur with or without patellar or quadriceps tendon tears and can cause anterior knee pain.
Pathology
Disruption and separation of prepatellar quadriceps conti...
Article
Berrettini anastomosis
Berrettini anastomosis is a common sensory interneural communication between the ulnar nerve and the median nerve in the palmar surface of the hand.
Gross anatomy
The Berrettini anastomosis is a purely sensory anastomosis between the common palmar digital nerves that arise from the median and ...
Article
Buccolabial muscles
The buccolabial muscles form a subgroup of the facial muscles.
Elevators, retractors and evertors of the upper lip:
levator labii superioris alaeque nasalis (LLSAN) muscle
levator labii superioris muscle
zygomaticus major muscle
zygomaticus minor muscle
malaris muscle
levator anguli oris...
Article
Symphalangism
Symphalangism refers to ankylosis or synostosis of the interphalangeal joints (i.e. fusion of the phalanges) in either the toes or the fingers. Less commonly, the metacarpophalangeal joints may be affected.
Epidemiology
One study reports symphalangism of the fifth toe in ~55% (range 40-75%) of...
Article
Facial muscles
The facial muscles, also known as the muscles of facial expression or mimetic muscles (TA: musculi faciales), enable facial expression and serve as sphincters and dilators of the orifices of the face. These muscles differ from those of other regions in the body as there is no fascia deep to the ...
Article
Maxilla
The maxillae (or maxillary bones) are a pair of symmetrical bones joined at the midline, which form the middle third of the face. Each maxilla forms the floor of the nasal cavity and parts of its lateral wall and roof, the roof of the oral cavity, contains the maxillary sinus, and contributes mo...
Article
Cartilage
Cartilage or cartilaginous tissue is a resilient and type of connective tissue of mesodermal origin that forms an integral part within the musculoskeletal system and as a structural component in other organs.
Cartilage can be generally classified into the following main types:
hyaline cartil...
Article
Lymphatic drainage of the upper limb
Lymphatic drainage of the upper limb is via a series of deep and superficial channels that ultimately drain into the axillary lymph nodes.
Gross anatomy
Lymph from the hand and forearm drain from lymphatic plexuses via superficial channels that accompany the basilic and cephalic veins to a se...
Article
Intercalary bone
Intercalary bones are common discal ossifications that are usually triangular in morphology, found in the anterior annular fibers of an intervertebral disc, and are thought to be degenerative in etiology.
Differential diagnosis
limbus vertebra
flexion or extension teardrop fracture
Article
Proximal radioulnar joint
The proximal radioulnar joint is a pivot type synovial joint between the circumference of the head of the radius and the ring formed by the radial notch of the ulna and the annular ligament.
Gross anatomy
Joint capsule
The joint capsule encloses the joint; both it and the synovial membrane ar...
Article
Lunate
The lunate (os lunatum or semilunar) is one of the carpal bones and is a component of the proximal carpal row.
Gross anatomy
Osteology
The lunate is crescent-shaped with a proximal convex articular facet and a distal concave articular facet. On the medial surface is a square-shaped facet and ...