Anatomy Flashcards
Intramembranous ossification summary
Laws of Bone remodelling:
Wolff’s Law
Heuter Volkman’s
What are the roots of the musculocutaneous nerve?
C5, C6 and C7
What are the roots of the axillary nerve?
C5 and C6
What are the roots of the radial nerve?
C5, C6, C7, C8, T1
What are the roots of the median nerve?
C5, C6, C7, C8, T1
What are the roots of the ulnar nerve?
C8 and T1
What is the function of the musculocutaneous nerve?
Supplies the anterior arm - motor to biceps brachii, coracobrachialis, brachialis.
What is the function of the axillary nerve?
Motor to the teres minor and deltoid.
Sensory to the shoulder (deltoid badge).
What does the teres minor do?
A rotator cuff muscle, the teres minor stabilizes the ball-and-socket glenohumeral joint.
Laterally rotates the arm.
What is the function of the radial nerve?
Motor the posterior arm (tricep extensors), posterior forearm extensors - radial nerve opens the fist.
Sensory innervation to the arm, forearm and hand.
Sensory innervation to the posterior forearm and hand.
What is the function of the median nerve?
Sensory function to the lateral hand.
Supplies motor function to the anterior forearm and hand - pronators and flexors.
Thenar muscles.
What are the two common landmarks where lesions and compression to the median nerve may occur?
Cubital fossa and the carpal tunnel.
What are the two common landmarks where lesions and compression to the radial nerve may occur?
Radial groove on the humerus and the lower triangular space.
What is the function of the ulnar nerve?
Sensory to the medial hand.
Motor to the anterior forearm and hand - flexion and thumb adduction.
Hypothenar muscles
Where are the two landmarks where compression and lesion to the ulnar nerve can occur?
Posterior groove of the medial epicondyle
Cubital tunnel - can lead to cubital tunner syndrome - leads to the pain when you hit your elbow.
Map of sensory innervation
Where is Erb’s point?
In the upper trunk by C5 and C6
Erb’s palsy:
- Damage at Erb’s point affecting C5 and C6.
- Presents with loss of shoulder movement and elbow function. (Finger movement is intact at T1 is preserved.)
- Injured due to a sudden increase of the angle between shoulder and neck.
Klumpke’s paralysis affects which roots of the brachial plexus?
C8 and T1
Klumpke’s paralysis
- Lower trunk injury due to damage at C8 and T1.
- Loss of intrinsic hand muscle and long finger flexor movements.
- Hand paralysis and loss of forearm and hand sensation medially
- Abduction injuries:
- Falling from height and grabbing on causing upwards pull on the lower trunk.
- Obstetric complications
What is the most common brachial plexus injury?
Flail limb
Flail limb affects which roots of the BP?
C5 through to T1.
Flail limb
- Significant trauma is main cause
- Linked to MND and ALS when non-traumatic
- Complete loss of upper limb mobility and sensation • Severe muscular atrophy
- Surgical repair difficult
A surgical neck of humerus fracture is likely to damage which nerve?
- how does this present?
Axillary nerve
Results in loss of deltoid and teres minor function.
Humeral shaft fracutre is most likely to affect which nerve?
- How does this present?
Humeral shaft fracture = Radial nerve.
Loss of extension at elbow, wrist, hand and fingers.
Define dislocation:
No contact between the articular surfaces of the joint.
DR CUMA - for representation of brachial plexus nerve lesions.
Drop Radial
Claw Ulnar
Median Ape
Radial nerve lesion summary:
An ulnar nerve lesion presents with atrophy where?
Hypothenar eminence (pinky)
Ulnar nerve lesion summary:
Cannot cross fingers in good luck sign.
A median nerve lesion presents with muscle wasting where?
Thenar eminence - leading to ape hand.
Median nerve lesion summary:
What is this a sign of?
Osteoarthritis - indicated from the Herbeden’s nodes and Bouchard’s nodes.
