Flashcards in Anatomy Deck (18)
Brachial plexus: trunks
-extends from neck to axilla & supplies upper limb
-formed from ventral rami of C5, C6, C7, C8 & T1; branches from the ventral rami of C4 & T2 may contribute
Where do the C5, C6, C7, C8 & T1 ventral rami emerge from?
-between the anterior & middle scalene muscles
Where do the ventral rami of C5 & C6 unite and what does that union form?
-at the lateral border of the scalenius medics
-forms the upper trunk
-this then passes infero-laterally, dividing just above or behind the clavicle into anterior & posterior divisions
Ventral ramus of C7 anatomical path?
-continues as middle trunk
-then passes infero-laterally, to divide just above or behind the clavicle into anterior & posterior divisions
Ventral rami of C8 & T1 anatomical pathway?
-unite at anterior aspect of scalenus medium behind scalenus anterior to form the lower trunk
-passes infero-laterally, dividing just above or behind the clavicle into anterior & posterior divisions
Role of neural tissue
-prime role of nervous system - chemical & electrical communication
-optimal communication requires healthy nervous tissue
-responds to movement by sliding/moving next to adjacent tissue
-changes in intra-neural pressure with movement of the system
Neural anatomy: nerve fiber binding
-nerve fibers bound by innervated connective tissue: endometrium, perineurium, epineurium
Neural anatomy information
-extensive blood supply
-requires 20% of available oxygen supply
-highly metabolic tissue
-lymphatic system slower than other tissues
-antegrade & retrograde movement of proteins & neurotransmitters
-alteration of flow "sick neurons": affect target tissue, affects conduction, affects cell body
Biomechanics of the nervous system
-spinal canal is 7-9 cm longer in flexion than extension
-central & peripheral system must continue to function when stressed or loaded
-vascular/ion channels must continue to function with movement/stress
Cervical facet joints
-45 degree angle toward eyes
Consequences of cartilage changes in CS bone
-diseased cartilage produces friction - "popping"
C1 no cutaneous branch
-sensory of posterior fossa/suboccipitals, O/A joints, posterior fossa & upper dura
-motor - sub occipitals & pre-vertebrals
-occiput, posterior neck muscles "greater occipital nerve", semispinalis, splenius capitis, A/A medial/lateral joint, SCM, trapezius, pre-vertebrals
-sensory to occiput via "third occipital nerve"
-motor - supplies multifidus, SCM, trapezius, pre-vertebrals
-crosses C2-3 facet joint
Branches of Trigeminal Nerve
-any structure innervated by the trigeminal nerve & upper first three cervical nerves that are capable of generating nociceptive input can potentially lead to headaches, dizziness or disequilibrium