Trochlea
Encyclopedia
Trochlea is a term in anatomy
. It refers to a grooved structure reminiscent of a pulley's wheel.
Most commonly, trochleae bear the articular surface of saddle
and other joints:
It also can refer to structures which serve as a guide for muscles:
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
. It refers to a grooved structure reminiscent of a pulley's wheel.
Most commonly, trochleae bear the articular surface of saddle
Saddle joint
In a saddle joint the opposing surfaces are reciprocally concave-convex.-Movements:...
and other joints:
- Trochlea of humerusTrochlea of humerusThe medial portion of the articular surface of the humerus is named the trochlea, and presents a deep depression between two well-marked borders; it is convex from before backward, concave from side to side, and occupies the anterior, lower, and posterior parts of the extremity...
- Trochlear processTrochlear processThe two oblique grooves of the lateral surface of the calcaneus are separated by an elevated ridge, or tubercle, the trochlear process , which varies much in size in different bones.Its chief anatomical significance is as a point of divergence of the previously common pathway shared by the...
of the Calcaneus - The "knuckles" of the tarsometatarsusTarsometatarsusThe tarsometatarsus is a bone that is found in the lower leg of certain tetrapods, namely birds.It is formed from the fusion of several bones found in other types of animals, and homologous to the mammalian tarsal and metatarsal bones...
which articulate with the proximal phalangesProximal phalangesProximal phalanges are bones found in the limbs of most vertebrates. In humans, they are the bones at the base of a toe or finger, the prominent, knobby ends of which are often called the knuckles....
in a birdBirdBirds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
's foot
It also can refer to structures which serve as a guide for muscles:
- Trochlea of superior obliqueTrochlea of superior obliqueThe Trochlea of superior oblique is a pulley structure in the eye. The tendon of the superior oblique muscle passes through it. Situated on the superior nasal aspect of the frontal bone, it is the only cartilage found in the normal orbit....
(see also superior oblique muscleSuperior oblique muscleFor the abdominal muscle see: Abdominal external oblique muscleThe superior oblique muscle, or obliquus oculi superior, is a fusiform muscle originating in the upper, medial side of the orbit which abducts, depresses and internally rotates the eye...
). This use is the source of the name for the Trochlear nerveTrochlear nerveThe trochlear nerve is a motor nerve that innervates a single muscle: the superior oblique muscle of the eye....
.