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...
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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...
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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...
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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...
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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...
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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 ...
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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...
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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...
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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...
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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...
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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 ...
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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...
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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...
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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 ...
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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...
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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...
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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...
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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
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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...
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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 ...

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