Flashcards in Upper limb Deck (39):
What are the purposes of the human skeletal?
Framework for movement
Support of soft tissues of the body
Protection of vital organs
Help with movement
What is a joint and what are the 3 types?
A place where 2 or more bones articulate or where bone joins cartilage
There are 3 types:
What are the 6 types of synovial joints?
Ball and socket
What are the components of a synovial joint?
What does the stability of a joint depend on?
Size and arrangement of its articular surfaces
Ligaments and tone of muscles
How to osteoblasts carry out bone formation?
Lay down type 1 collagen sheets
Describe the differences between the 3 muscle fibre types
What is the sliding filament theory of contraction?
Calcium channels release calcium from the sarcoplasm into the sarcoplasmic reticulum post activation of an action potential - calcium binds to troponin causing it to change shape - tropomyosin is pulled away from binding sites - myosin heads move into an extended position by phosphorylation ADP - myosin binds to actin forming a cross bridge - myosin moves actin along using ATP - sarcomere shrinks - myosin head unwinds with actin after using up energy
What causes tetanus? Describe the mechanism of the disease
Clostridium tetani causes tetanus
The toxin enters the nervous system through the blood - travels up the axon to cell body in spinal cord - crosses the synaptic cleft between the motor and inhibitory interneuron - inhibitory interneuron prevents motor neurone from continuously firing - leads to unopposed muscle contraction - can lead to fractures, tendon ruptured and death if untreated
What occurs at the terminal bud of a nerve at the neuromuscular junction during an action potential?
At axon hillock, sodium enters after a stimulus is reached causing an action potential - influx of sodium causing influx of calcium at the axon terminal - intracellular calcium acts on vesicles which later fuse at the terminal membrane to release acetylcholine - acetylcholine is released into synaptic cleft via exocytosis
When do limb buds appear on a foetus?
Towards the end of the 4th week of pregnancy
What is syndactyly and what are the 2 different types?
Fusion of digits
Cutaneous syndactyly - fusion of skin between digits
Osseous syndactyly - fusion of bone between digits
What 2 ligaments join the clavicle to the coracoid process and how can they be torn?
Coraclavicular ligaments - trapezoid ligament (lateral) and consider ligament (medial)
Can be torn from an acromioclavicular joint dislocation
Which movement does the deltoid muscle NOT do to the shoulder?
Which muscles does the axillary nerve supply?
How can damage to the axillary nerve occur?
Surgical neck of humerus fracture
Which muscles make up the rotator cuff?
What are the 3 joints in the shoulder complex?
Falling on an outstretched hand can lead to what possible injuries?
Dislocation of the glenohumeral joint
Fracture of clavicle
Which 3 things form the coracoacromial arch?
What is painful arc syndrome and what are the symptoms?
Pain caused by the supraspinatus tendon rubbing under the coracoacromial arch which can lead to bursitis, supraspinatous tendonitis, degeneration and rupture of a tendon
Symptoms include pain during abduction
What structures can become fractured following a mid-shaft humeral fracture?
Profunda brachii artery
Which nerve roots are part of the brachial plexus?
C5 to T1
What is Erb’s palsy?
Injury to the superior parts of the brachial plexus resulting in paralysis of the shoulder and arm muscles presenting with the waiter’s tip appearance
What muscles can be found in the arm (shoulder to elbow)? Where are they in relation to each other?
Which muscles of the upper arm do the musculocutaneous nerve and radial nerve supply?
Musculocutaneous - biceps, brachialis and coracobrachialis
Radial - triceps
Describe the anatomical location of these nerves in relation to the humerus? Musculocutaneous, median, ulnar and radial
Musculocutaneous- anterior to the humerus
Median - medial to the humerus
Ulnar nerve - medial to humerus, posterior to medial epicondyle
Radial nerve - posterior and lateral to humerus
Where is the cubital fossa location and what are the landmarks?
A triangular region located anterior to the elbow
Brachioradialis - lateral border
Pronator teres - medial border
Inter-epicondylar line - superior border
What movements do the muscles of the anterior compartment of the forearm do?
Flexion of the wrist
Pronation of the wrist
Which nerve supplies most of the anterior forearm muscles?
Flexor Capri ulnaris - only ulnar nerve supplied
Which nerve supplies the posterior forearm muscles?
What is tennis elbow? What is golfer’s elbow?
Tennis - inflammation of the lateral epicondyle
Golfer’s - inflammation of the medial epicondyle
What movements does the elbow joint allow?
What is carpal tunnel syndrome and what are the signs and symptoms?
Pressure on the median nerve where it passes through the wrist
Symptoms include sensory loss, paraesthesia and pain in lateral 3.5 digits
What 5 components can be found in the anatomical snuff box?
Radial styloid process
Base of the 1st metacarpal
What are the main causes of nerve injury in the upper limb?
What are the typical signs and symptoms of a fracture?
Loss of function
What factors influence bone healing?
Type of injury
Type of bone injured