Upper_lower_limb homologies Flashcards
What can Elbow do that knee cannot?
Suppination and pronotation
Main difference between Thumbs and big toes?
Thumbs are opposable
Main differences in function of arms vs. Legs
Arms: grasping + fine movements of fingers; Legs: support weight, standing, walking
Explain homology of extremities during development
Bothupper and lower expremtities start as buds that project perpindicular to spinal column; begin to rotate in diff directions
Describe movement that lends to different orientations
upper extremity rotates laterally (palms forwad); lower extremity rotates medially (soles of feet back and down)
In dermatomes of upper extremity, do higher spinal nerves orient laterally?
Yes. Thumb=C6, Pinky= C8 (lower); opposite in lower extremity (lower extremity- highler spinal levels at medial dermatomes; Big toes= L4, little toes= S1)
What are the Lower Extrem equivs of upper extrem attachment limb?
Scapula + Clavicle = Innominate bone
What are the lower extrem equivs of Humerus, radius and ulna?
Prox: Humerus= femur; Distal: Radius + Ulna = Tibia + fibula
What are lower extrem equivs of wrist bones?
Carpals = Tarsals
What are lower extrem equivs of hand bones?
Metacarpals + Phalanges = Metatarsals + Phalanges
What are major movements of arm:shoulder?
1)AD/AB; 2) Flx/Ex (up/down); 3) flx/Ex (ant/post) 4) lat/med rotation; 4) Circumduction (circ mvmt)
What are other movements of arm?
1) forearm:elb Flx/Ex; 2) hand:wrist Flx/Ex; 3)palm:elbow Protonation/suppination
Which movement is major difference of mvmt b/w elbow and knee?
Protonation (palm down- radius crosses over ulna) and Supination
Do you know all of the landmarks on scapula and humerus?
Check diagram- 16 of them
What is a separated shoulder?
fall on shoulder–> dislocation of acromioclavicular joint; clavicle elevates and scapula falls away–> tear coraco-clavicular and acromioclavicular ligaments
What is difference b/w ball and socket joint at hip vs. shoulder?
Shoulder socket (glenoid fossa)= shallower to shoulder than acetabulum is to hip.
What is Dislocation of glenohumeral joint?
head of humerus driven infiorly through weakness in joint capsule (no rotator cuff to stabilize shoulder)
Where are the two joints in elbow? Which movements do they give?
Hinge joint-Flx/Ex forearm= Humerus:ulna; Rotational Joint= humerus: radius (Forearm supination, pronation)- radius crosses ulna
Describe “Wrist pull”?
dislocation by annular ligament (holds radius against humerus and links ulna to radius)
Where is upper limb equiv of interosseus membrane?
b/w ulna and humerus (LL= tibia and fibula)
Do tendons in hand enter from same direction as those entering ankle?
NO. Tendons go through midline of wrist to enter hand; enter foot from lateral/medial sides of ankle
Which fascial layer protects underlying tendons in hand?
Palmar aponeurosis - Superficial fascial layer (like plantar aponeurosis)
What prevents bowstrining of tendons in both hands and feet?
Retinacula (fibrous sheeths that make tunnels)
What are the bones of the hand?
See Chart
Which nerves innervate the hand?
Median nerve and Ulnar Nerve (like medial/lateral plantar nerves)
What is layer arrangement of hand?
There are 4 layers (like in foot)
Which tendons are in layer 1?
flexor digitorum superficialis and abductors pollicis & digiti minimi
Which tendos are in layer 2?
flexor digitorum profundus and lumbricals
Which tendons are in layer 3?
ADDuctor pollicis (oblique and transverse heads) and Flexor Pollicis Longus
Which tendons are in layer 4?
Palmar (PAD) interossei and Dorsal Interossei (DAB)
Are nerves of heand compartmentalized like that of leg/foot?
yes
Which nerve gives rise to ulnar and medial nerves?
Musculocutaneous Nerve (elbow and wrist flxn/extns)
Which nerves innervate anterior and posterior arm?
Ant= Musculocutaneous nerve; Post = radial nerve
Describe innervation of anterior forearm muscles
Ant= Median nerve innervates all muscles except those done by ulnar nerve: Flexor carpi ulnaris and 1/2 of flexor digitorum profundis
Describe innervation of posterior forearm
Post= radial nerve
Do you know the innervation of hand?
See table
What is equivalent of foot drop in hand?
Wrist drop- caused by damage of radial nerve in axilla
In foot drop which muscles lose innervation?
Lose extention @ Triceps brachii in arm and extensors of forearm. No sensation post arm/foraem, dorsolat hand, dorsoprox of lat 3.5 digits
Equivalent upper extrem equiv to lumbosacral plexus of pelvis?
Brachial plexus (more susceptible to damage)
Describe divisions of artery in Arm
Subclavian–> axillary (armpit)–> brachial (arm)–> (forearm) Radial + Ulnar (differences in location reflects medial rotation)
Where are the anastamoses in arm?
Shoulder and elbow
What is major branch of brachial artery?
Profunda Brachii
What are the arterial arches of hand?
Deep palmar arch from radial A and Superficial Palmar arch from ulnar A.
