[001] Organisational Patterns Of Limbs Flashcards
What are stylopods, zeugopods and autopods?
Stylopods - single, most proximal elements (humerus, femur)
Zeugopods - double, middle element (radius/ulna, tibia/fibula)
Autopods - multiple elements, most distal (carpals, phalanges)
What is the anatomical position?
Palms and toes face forward
What is the coronal/frontal, transverse/axial and sagittal plane?
Coronal: plane cuts through side of body
Transverse: plane is parallel to the ground and cuts through the body
Sagitta: plane cuts through the front of the body
In limb development, which segments of the spine eventually form the upper and lower limbs?
Upper limb: C5 - T1
Lower limb: T1 - S3
What is a tetrode?
A vertebrate with 4 digitated limbs
What are the parts of the limb in terms of evolutionary changes?
- The central axis (bone element of the limbs)
- Preaxial border (controlled by ventral muscles)
- Postaxial border (controlled by dorsal muscles)
What movement do dorsal muscles cause?
lifting/extending
What muscles do ventral muscles cause?
lowering/flexion
How have the limb organisation changed through evolution?
The limbs have been rotated 90° around the central axis. The lower limbs rotate backwards and the upper limbs rotate forwards into the anatomical position. The forearm pronates to point the digits forward.
Where are the ventral muscle groups in the anatomical view of the body?
In the anterior view, they are in the torso and in the posterior view, they are in the legs
Where are the dorsal muscle groups in the anatomical view of the body?
In the anterior view they are in the legs and tops of shoulder and in the posterior new they are in the back and arms.
What are the 3 parts of the upper limb muscle groups?
- Elbow flexors/extensors
- Shoulder flexors/extensors
- Wrist and finger flexors/ extensors
What are the upper limb movements?
- Flexion/extension
- Adduction/abduction
- Medial/lateral rotation
- Circumduction
- Pronation/supination
What are the 3 lower limb muscle groups?
- Hip flexors/extensors and abductors/adductors
- Knee extensors/flexors
- Ankle and toe extensors/flexors
What are the lower limb movements?
- Extension/flexors
- Abduction/adduction
- Dorsiflexion / plantarflexion
What occurs during weeks 5-8 in the embryology of limb rotation in humans?
Week 5: limb bud position is similar to hypothetical fish ancestor
Week 6: limbs bend anteriorly and the elbows and knees point laterally, palms and soles face the trunk
Week 7: Limbs undergo 90° rotation around central axis but in opposite directions so elbows point candally and knees point cranially
Ween 8: The limbs rotate 90° latero-medialy, bringing the limbs under the trunk
What is myotome?
A group of muscles who receive their moder innovation from a single spinal nerve
