Lecture 23 - Forearm and Hand Flashcards
Forearm is
between elbow joint and wrist joint
Hand is
from wrist joint onwards
Elbow joint is a
synovial hinge joint
Function of elbow
forearm flexion and extension (i.e. the movements involved in a bicep curl)
Elbow joint is made of 3 different bones…
Humerus
Ulna
Radius
Coronoid process
on the ulna for brachialis
Radial tuberosity
on radius for biceps brachii
Anatomical postion - order of the forearm bones
Radius, Ulna, Middle (RUM)
Proximal radio-ulnar joint is a
synovial pivot joint
Pivot joint
Uniaxial
A rounded process of bone fits into a bony ligamentour socket, permitting rotation
Nerve behind medial epicondyle of humerus =
ulnar nerve
Capitulum
more rounded structure
on the lateral side of the humerus
Trochlear notch
of ulna pulley more 'w' in shape medial fits the trochlea of the humerus
Radial notch
of ulnar
part of the ulnar
bit concave to accomodate for radius
Radio-ulnar joints are between
radius and ulnar
Proximal radioulnar joint and ligaments
Ligaments aid stability
Anular ligament • Laxity in childhood • Yanking movements can dislocate the radius • Potential damage to ligament • aka Nursemaid’s elbow
Anular ligament
Anular ligament
• Laxity in childhood - so need to take care and be careful with childrens arms and pulling on them with a large amount of force
• Yanking movements can dislocate the radius - head of radius comes off ligament
• Potential damage to ligament
• aka Nursemaid’s elbow
distal radioulnar joint is a
synovial pivot joint
Distal radioulnar joint
- For pronation and supination
* Has an articular disc to allow twisting of joint capsule during pronation
Pronation in terms of radius
only the radius moves in pronation, croses over the ulna
Supination in terms of radius
radius and ulna parallel to one another
Pronation and supination happens
at the radiuolnar joints (have proximal and distal ones)
distal radioulnar joint has a disc to attach to ulna (articular disc is made up of fibrocartilage)
Cubital fossa is a triangular space bordered by…
Pronator teres
Brachioradialis
Epicondyles
^ think of triangle opposite to this i.e. with base up
base is lateral epicondyle ——medial epicondyle
Left border is brachioradialis (more lateral)
RIght border is pronator teres (more medial)
Nearby structures to cubital fossa
Brachialis Biceps brachii Median cubital vein Brachial artery Median nerve
Median cubital veins connects
the cephalic vein and the basilic vein
Forearm muscles - pronators for pronation
pronator teres
pronator quadratus
Forearm muscles - supinators for supination
Biceps brachii
Supinator (on lateral side)
pronator teres
quite superficial
pronator
part of cubital fossa
anterior
pronator quadratus
deep
pronator
anterior