LOCO4 Flashcards
Brachial plexus
What are the anterior cord nerves [3]
What are the posterior cord nerves [2]
Anterior cord (lateral to medial)
* Musculocutaneous
* Median
* Ulnar
Posterior cord
* Axillary
* Radial
Describe scapulo-humeral rhythm [2]
Scapula and humerus move in a 1:2 ratio.
When the arm is abducted 180 degrees, 60 degrees occurs by roation of the scapula and 120 degrees by rotation of the humerus at the shoulder joint
Which nerves [2] and muscles [2] are at risk of from axillary lymph node clearance? [2]
Injury to thoracodorsal nerve; Latissimus dorsi
Injury to long thoracic nerve; serratus anterior - causes winging scapula
Sternoclavicular joint:
What is the type of joint? [1]
Which structure is present for shock absorption? [1]
Which type of movement does the joint permit? [1] ?
joint type: synovial, saddle joint
shock absoption: articular disc
movements: around 60 degrees when elevate scapula
what are two prominent structures / features of the the glenohumeral joint? [2]
Why is this clinically significant [1]
what are two prominent features of the glenohumeral joint?
glenoid cavity accomodates approx/ 1/3 of the humeral head: means that should can have wider range of movement
inferior joint capusule is lax. allows elevate above head. but means is much weaker than superior portion
Which structures deepen the shallow glenoid fossa? [2]
what is the shallow glenoid fossa deepened by? [2]
- glenoid labrum (fibrocart. ring that surrounds articular surface). helps deepen the socket and support the joint
- long head of the biceps - attaches to superior aspect of labrum
Which of the following is the glenoid labrum?
A
B
C
D
E
Which of the following is the glenoid labrum?
A
B
C
D
E
Which of the following is the acromion?
A
B
C
D
E
Which of the following is the acromion?
A
B
C
D
E
Which of the following is the scapula?
A
B
C
D
E
Which of the following is the scapula?
A
B
C
D
E
Which of the following is the supraspinatus muscle?
A
B
C
D
E
Which of the following is the supraspinatus muscle?
A
B
C
D
E
Which of the following is the glenoid labrum
A
B
C
D
E
Which of the following is the glenoid labrum
A
B
C
D
E
Which of the following is the glenoid cavity
A
B
C
D
E
Which of the following is the glenoid cavity
A
B
C
D
E
What is muscle D? [1]
What is bone E? [1]
D: supraspinatus
E: Acromion
Which of the following is the articular capsule
A
B
C
D
E
Which of the following is the articular capsule
A
B
C
D
E
Which of the following is the articular capsule
A
B
C
D
E
Which of the following is the articular capsule
A
B
C
D
E
where do each of the following arrive from?
- Muscularcutaneous
- axillary
- median
- radial
- ulnar nerve
where do each of the following arrive from?
- Muscularcutaneous: C5-C7
- axillary: C5-C6
- median: C5-T1
- radial: C5-T1
- ulnar nerve; C8-T1
What is Erb’s palsy caused by damage to? [1]
which nerves? [3]
what does it result in? [3]
Erbs palsy:
- Damage to the superior trunk of the brachial plexus.
- This happens quite commonly in difficult birth (pulling the head away from the upper limb) results in nerve palsy.
- Damaging C5 and C6 mainly affects musculocutaneous, axillary and medial nerve. It results in:
- Adducted shoulder
- Medially rotated arm
- Extended elbow
Label A-E
A: bicep brachii
B: triceps brachii
C: brachioradialis
D: subscapularis
E: Axillary artery
Label A
Brachioradialis muscle
Label A-C
A: Coracobrachialis muscle
B: Teres major
C: Medial head of triceps brachii muscle
Label A [1]
supinator muscle
what is 1 & 2?
2 coracobrachialis
1. brachialis
Bicep brachii
Where do the 2 heads of the bicep brachii attach? [2]
The two heads join together and attach onto which bone? [1]
Describe the movements of the bicep brachii muscle [2]
Location of 2 heads:
- short head - found medially. attaches to corocoid process
- long head - found laterally (L4L) attaches to supraglenoid tubercle
Join together to form one muscle, together inserts onto radius at the radial tuborisity
movements:
- powerful supinator
- flexor and shoulder and elbow
Pronation of the forearm is undertaken by pronator quadratus (deep layer) and pronator teres muscle (superficial layer).
which of these is the main muscle involved in pronation and which assists pronation?
pronator quadratus (deep layer): main
pronator teres muscle (superficial layer): assists
lumbricals: flex MCP
dorsal interrossei: abduct fingers (DAB)
palmar interrossei adduct the fingers (PAD)
Label B & C
B = thoracodorsal
C = long thoracic
Label A-C
A: Pec major
B: serratus anterior
C: long thoracic nerve
Which of the following drug treatment causes muscle damage by creating lysosomes in muscle tissue
Statins
Hydroxychloroquine
Corticosteroids
Prednisilone
Hydroxychloroquine
This sign tests which nerve
Radial
Median
Axillary
Ulnar
Median
Describe what a target fibre is [1]
Why does a target fibre arise? [1]
Describe the apperance [1]
When a damaged muscle is re-innervated; nuclei of muscle moves centrally and causes the production of new actin and myosin fibres
Occurs due to satellite cells differentiating and proliferating
How does an EMG present with patients who have myopathy?
Compared to healthy and neuropathy patients [2]
In myopathic motor units, the number of functional muscle fibers is reduced. Therefore motor unit action potentials (MUAPs) are smaller in amplitude and duration. Because of the asynchronous firing of affected muscle fibers, the morphology of MUAPs become polyphasic.
How does a patient with dermatoymositis present? [4]
Rash around eyes
Peri-orbital oedema
V sign of neck due to increased photosynsetivity
Gottron’s sign
How does a biospy from a patient with polymyositis / dermatomyositis present? [1]
- (some have subclinical muscle involvement)
- Muscle generally not involved; CD8 T cells cells infiltrate the periphery of the muscle fasicle
- Central nuclei
- Variation in fibre size
How does early DMD appear histologically? [3]
Fibre size variation
endomysial & perimysium fibrosis
Degenerating muscle fibres undergoing myophagocytosis
How does late DMD appear histologically? [2]
Loss of muscle; atrophy of fibres and death - replaced with fibrotic material and fat
How do statins affect 10% muscle? [2]
Rhabdomyolysis; get vacuoles in type 2 muscle fibres
Name and describe how two therapeutic drugs cause myopathy [2]
Corticosteroids; cause dose dependent type 2 atrophy
Hydroxychloroquine: not dose dependent atrophy; lysosomes damaged
Hydroxychloroquine causing lysosome damage
What is a Jefferson Fracture? [1]
bone fracture of the vertebra C1
What is Hangman’s fracture? [1]
fracture which involves the pars interarticularis of C2 on both sides, and is a result of hyperextension and distraction.
Pectoralis major and latissimus dorsi are both adductors of the shoulder, and they attach to the proximal humerus. Normally, the clavicle holds the arm laterally away from the body, but this fracture causes it to collapse. The humerus is pulled medially, dragging the lateral fragment of clavicle with it.
On the MRI below, a tendon passing deep to the acromion appears thickened and abnormally bright. To which muscle does this tendon belong? [1]
Acceptable responses: supraspinatus
Which structure(s) is (are) most at risk in the injury below? Select all that apply.
What type of fracture causes superior gluteal nerve damage? [1]
sacroiliac joint disruption
How can you classify intracapsular neck of femur fractures? [3]
How can you classify extracapsular neck of femur fractures? [2]
Intracapsular fractures include subcapital, transcervical and basicervical.
Extracapsular fractures include intertrochanteric and subtrochanteric.
How does local acupuncture work? [4]
Stimulates nerve fibres in skin and muscle
Vasodilation / Blood vessel proliferation
Nerve growth
Acupuncture promotes local healing
