week 4 movement Flashcards
what 3 bones is the elbow joint composed of?
the humerus, ulna and radius
what forms humero-ulner articulations?
the trochlear of the humerus and the trochlea notch of the ulner forms the articulation
what forms humero-radial articulations?
the capitulum of the humerus and the upper surface of the radius head
what is the positioning of the ulna and the radius?
ulna –> medial
radial –> lateral
what is the ligament reinforcement of the elbow joint?
laterally by the radial collateral ligament
medially by the ulna collateral ligament
what two directions is the elbow joint not reinforced and why?
it is not reinforced posteriorly or anteriorly. This allows the elbow to flex and extend
which bone in the elbow joint is responsible for stability?
the trochlea and the trochlea notch of the ulna. The radial does not play a part in stability of the elbow joint
how does posterior dislocation occur and how common is it?
80-90% of dislocation. The distal end of the humrus is driven through the weeken anterior part of the joint capsule
what are the two causes of posterior dislocation?
land on the arm flexed
or land on the arm when is fully hyperextension which causes the elbow to pop out posteriorly or postolaterally
what associate injuries can occur with posterior dislocation
Ulnar collateral ligament torn
Fractures- head of radius, coronoid process, olecranon process
Ulnar nerve injury
what are the symptoms of posterior elbow dislocation?
server pain, widened area of the elbow region, prominant olecranon process
which nerve can posterior dislocation damage and what is the consequence
ulnar nerve be damaged. It is part of the brachial plexus and can cause numbness on the medial part of the palm and the fingers. Also weekness of flexion and adduction of the wrist.
what is simple elbow dislocation?
where there is no fractures of the bone around the elbow joint and only the ligament is damaged. No need for surgery
what is a complex elbow dislocation?
it is usually associated with fracture of the forearm. Surgery is often needed to fix the brocken bone and keep the elbow joint in correct place
what are two movements of the elbow joint?
flexion and extension
how far can the elbow usually extend and what is stopping it from going any further?
it can usually extend ot 180 degrees and usually the olecranond process of the ulna fits nicely into the olecranond fossa of the humerus. Not allowing it to extend any more. Bone on bone
what happens in hyperextension?
this is when the elbow can extend pass 180 degrees. There is a hole in the humerus called olecranond fossae which allows the olceranond process of the ulna to pass through the humerus and extend further
what are the three muscles of flexor?
bicpe brachii, brachialis, and Brachioradialis ( is a acessory flexor muscle that aides brachialis)
what compartment are the flexor muscles on the forearm?
the anterior compartment however the brachioradialis is in the posterior part and classed as a extensor but moves anteirorly when arm is being flexed
what is the main muscle involved in flexion?
brachialis
what is the muscle of extension of the elbow joints and how many parts does it have?
tricep brachii
long head, medial head and lateral head
what are the origions of each part of the tricep brachii and what is there innervation and how do they attatch to the elbow joint?
Long head - Infraglenoid tubercle (scapula)
Lateral head - Posterolateral humerus above spiral groove
Medial head - Posteromedial humerus below spiral groove
supplied by the radial nerve C5-T1
insertion at the olecranon process of the ulna the 3 parts come togehter as one –> tricep tendon
what protects the olecranon process?
the olecranon bursa –> contains synovila fluid
what is olecranon burisitis?
it is when the olecranon bursa is excessive, repeated pressure and friction over the olecranon can cause inflammation of the bursa –> cause swelling and pain.
what articulation is involved in Proximal Radioulnar Joint?
the head of the radius and the radial notch of the ulna
what is the function of the alunar ligament?
it wraps around the head of the radius, stables the radius and allows the rotation of the radius when supination and pronation of the forearm.
when is it most common to dislocate your anular ligament?
before the age of 4 and usually occurs when pulling the child up by one arm or lift the child. The radius is more prone to dislocation
what is supination and pronation of the forearm?
In supination the palm is facing up and in pronation the palm is facing down
what nerve and muscles are involved in the rotation from supination of forearm to pronation?
the median nerve and is the contraction of pronator teres and pronator quadratus
what nerve and muscles are involved in the rotation of the forearm from pronation to supination?
radial nerve and Musculocuanteous nerve. The bicep brachii and supinator contract
what is the primary function of the bicep brachii?
to supinate the arm and can only use the bicep brachii in the supinated position
what are the two common sights where insertions of tendons into bone becomes inflamed?
lateral and medial epicondyle
medial epicondyle commonly caused by golf
lateral epicodnyle caused by tennis
what muscle type attatches to the medial and lateral epicondyle?
the wrist flexor muscles for the medial
the wrist extensor muscles for the lateral
what is the symptoms where there is inflammation at the epicondyle?
symptoms are Local tenderness. Pain radiates into forearm on along the affected muscles
treatment–> rest, anti inflammatory or injection of corticosteriods if the pain is very bad
what part of the epicondyle can alvusion happen and why?
the medial epicondyle ossifies seperatly from the humerus and is only attached to the cartiladge until the age between 14-20 when it fuses. Trauma can cause the ulnar collateral ligament to stretch which pushes the medial epicondyle out of place –> which can cause damage to the ulnar nerve
wher does humerus fracture take place?
at the surgical neck not the anatomical because there is a narrowing and weekness at teh surfical neck part. Can damage the axillary nerve region
how can you test if the axillary nerve is damaged?
test the deltiod musclea and sensation in the regimental badge area
what occurs in the Humeral shaft fracture?
there is radial groove where radial nerve runs on the posterior surface of the humerus. Is a weekening at this position. Fracture here will cause the deltiod which is attached to the humerus more superiorly will pull the proximal part of the humerus laterally. Get a gap between the two fractures and can damage the radial nerve which controls the extensor part of the arm. Can lead to paraylse of the muscles controlling the extensor part of the forearm and fingers
what is Supracondylar?
most commonly occurs to children. If the humerus is fractured and displaced anteriorly can damage both the brachialm artery and median nerve which supply the anterior flexor muscles of the forearm. It can lead to paraylse and if damage to the arm –> hypoxia, turning blue and eventually necrosis –> dead tissue if not dealt with quickly
damage to the ulna nerve causes damage to which muscle? what is the outcome?
flexor carpi ulnaris –> controls flexion of your wrist
what does the cephalic vein drain and where does it originate from?
it originates from the anatomical snuff box at the base of the thumb.
drains the posterior and lateral surface of the arm, forearm and hand.
how does the cephalic vein drain into the axillary vein?
it enters the clavicopectoral triangle in the arm, then penetrates the deep fascia to get to the axillary vein
what does the basilic vein drain and what is its origion?
basilic vein originates from the dorsal venous network of the hand–> drains the postomedial surface of the forearm and hand.
where does the cephalic and basilic vein both originate from?
the dorsal venous network of the hand
what is the route of the basilic vein?
it runs postomedially up the forearm and then goes onto the anterior limb just inferior to the elbow joint –> carries up half way up the arm and the penetrates the deep fascia - fascia –> to join the deep veins to form axillary vein
what is the lateral wall of the axillia made up off?
intertubercular sulcus
what is the medial wall of the axillia made up of?
serratus anterior, 4th rib and upper thoracic wall
what is the anterior wall of the axillia made up off?
pectroalis minor and major, subclavius and clavicopectoral fascia
what is the posterior wall of the axillia made up off?
subclavius, subscapularis, teres major, lattismus dorsi
what is the relation between the pectoralis minor and brachial plexus?
in the axillia the pectoralis minor lies over the brachial plexus
what tendons form the anatomical snuff box?
the roof is formed by the extensor pollicis longus
the floor is mad up of the extensor pollicis brevis and abductor pollicis longus
