Brachial plexus Flashcards
The brachial plexus is made by the ventral rami of C__ to T__.
C5 to T1
What other rami send contributions to the brachial plexus?
C4 and T2
The brachial plexus is formed between what two muscles?
anterior and middle scalene
The branches of the brachial plexus can be classified into what two groups?
- Supra-clavicular
2. Infra-clavicular
Where do the supra-clavicular branches arise from?
roots, or the trunks of the plexus
Where do the infra-clavicular branches arise from?
cords of the plexus
In ___% of the normal population the fibres of the brachial plexus can be in the middle scalene.
30
any branch coming from a cord is _______.
infraclavicular
What is the most important nerve of the arm?
radial
What are two examples of injuries where the brachial plexus could be injured, leading to Erb’s palsy?
- birth
- falls
(when angle between head and shoulder is suddenly increased)
What trunk is involved in Erbs palsy?
Upper trunk (C5-C6)
What movements are lost in Erb’s palsy?
- Most of the movements of the shoulder
- Flexion of elbow
- Extension of wrist joint
What trunk does Klumpkes palsy involve?
lower trunk (C8-T1)
What muscles are effected by Klumpkes palsy?
- Flexor muscles of wrist and fingers
- Intrinsic muscles of the hand
What type of accident commonly causes Klumpkes palsy?
falling accidents when person tries to hang on to something to avoid falling (angle between arm and trunk)
