Week 119 - Shoulder trauma Flashcards
Week 119
why does vit c deficiency cause scurvy?
cofactor for hydroxylases
what analgesic provides retrograde amnesia?
midazolam
what amino acids are primarily found in collagen?
lysine and proline
why is the shoulder commonly dislocated?
unstable
what is an example of a disease involving mutations in type 1 collagen
osteogenesis imperfecta
a tear in what can cause pain in the shoulder?
glenoid labrum
what is an example of a disease involving mutations in type 2 collagen
chondrodysplasia
what type of dislocation is caused from the division of the acromioclavicular and coracoclavicular ligaments
acromioclavicular dislocation
what is an example of a disease involving mutations in type 3 collagen
ehlers-danlos syndrome
what is prominent from a AC dislocation?
distal clavicle
what would a patient present with if they had osteogenesis imperfecta?
weak bones
where do clavicle fractures usually occur?
lateral end
what would a patient present with if they had chrondodysplasia?
abnormal cartilage, joint and bone deformities
what type of dislocation is common from a high energy injury like a road traffic accident?
sternoclavicular dislocation
what would a patient present with if they had ehlers danlos syndrome?
fragile skin, blood vessels, hypermobile joints
what are the rotator cuff muscles?
supraspinatous infraspinatous teres minor subscapularis
extracellular matrix is also made up of what else apart from collagen
proteoglycan and non-collagenous proteins
what is the action of supraspinatous
abduction
what non-collagenous protein stimulates bone/cartilage formation?
bone morphogenic proteins
what is the action of infraspinatous
lateral rotation
what non-collagenous protein regulates bone mineralisation?
osteopontin, osteonectin, osteocalcin
what is the action of teres minor
lateral roation
what type of bone is where crystals lie inside the collagen fibrils?
lamellar bone
what is the action of subscapularis
medial roation
what type of bone is where crystals lie outside the collagen fibrils?
woven bone
what nerve innervates supraspinatous
suprascapular nerve
what type of bone is unmineralised
osteoid bone
what nerve innervates infraspinatous
suprascapular nerve
rickett’s and osteomalacia are examples of disease involving what malfunction in osteoid?
doesn’t calcify
what nerve innervates teres minor
axillary nerve
name the cell - precursor cell which differentiates into bone forming cells
osteoprogenitor
what nerve innervates subscapularis
subscapular nerve
name the cell - deposits osteoid and controls mineralisation
osteoblast
posterior shoulder dislocation is important because of?
major vessels
name the cell - become surrounded by newly formed bone and are derived from osteoblasts
osteocyte
what investigation can be performed is there is suspected damage from a dislocation?
CT
name the cell - involved in bone resorption
osteocyte
which rotator cuff muscle is only responsible for 15 degrees of movement in abduction?
supraspinatus
what are the cavities called in which osteocytes reside in bone?
lacunae
if a patient cannot externally rotate their shoulder far what condition does it indicate
frozen shoulder
what structures link lacunae together
canaliculi
restriction of active movements during assessment of the shoulder suggest pathology of what?
rotator cuff muscles
where does bone mineralisation homeostasis take place?
spongey bone
restriction of active and passive movements during assessment of the shoulder suggest pathology of what?
shoulder joint itself
what is a distinctive pattern of arranged lamellae around a central canal
haversian system/osteon
what test is done for impingement of the shoulder?
hawkins-kennedy
what is composed of chondrocytes within ECM rich with proteoglycans?
cartilage
what is shoulder impingement?
impingement of the tendons of the rotator cuff muscles causing inflammation
what type of cartilage is articular cartilage made up of?
hyaline
what test suggests capsulitis
scarf test
what type of cartilage forms growth plates?
hyaline
what test is used for shoulder instability/anterior dislocation?
apprehensive test
what type of cartilage links the ends of ribs to the sternum?
hyaline
a patient presents with shoulder pain and the inability to perform overhead activities, they are also finding it difficult to sleep
impingement
what type of cartilage has elastic fibres scattered in the ECM?
elastic
thickening of the joint capsule
adhesive capsulitis
what type of cartilage forms the annulus fibrosa of the intervertebral discs?
fibrocartilage
what clinical features can present with impingement?
bony spurs
what are catilage cells called?
chrondocytes
shoulder pain can also be the result of referred pain from which nerve root?
C5
why does articular cartilage lack a perichondrium
compression would occlude vessels
adhesive capsulitis is associated with what chronic condition?
diabtes
which zone of cartilage is first degraded in OA?
superficial zone of uncalcified cartilage
What is the large, aggregating proteoglycan that is present in cartilage and that traps water?
aggrecan
Why is the trapping of water by this proteoglycan important for the mechanical properties of the tissue?
gives the joint ability to resist compressive loads
What is the name of the cavity in which a chondrocyte lies (similar to an osteocyte)?
lacuna
Where is elastic cartilage found?
epiglottis, ear
Where else is fibrocartilage found?
ligament/tendon enthesis
what causes impaired collaegn synthesis?
vit c deficiency
what is the main analgesic used in a dislocated shoulder injury?
morphine
what condition is caused by impaired collagen sysnthesis?
scurvy
what is the condition described by when two articular surfaces are partly in contact and presents with symptoms of dislocation
sublaxation
what investigation can be used to look into a joint?
arthroscopy
what is bone ECM primarily made up of?
collagen type 1
what is the critical component in a dislocation?
force
what four factors of force are important in a dislocation?
magnitude, direction, speed and duration
what secretes collagen type 1?
osteoblasts
what nerve can be damaged from a dislocated shoulder?
axillary nerve
What is a Hill?Sachs lesion?
a depression in the posterolateral head of theÿhumerus bone
Muscles effected in Erb?s palsy?
Abductors and external rotators of the shoulder are affected
Where is the weakest position for the shoulder joint?
abducted to 90 degrees and externally rotated
Signs of Klumpke?s paralysis?
Ulnar claw hand deformity
Signs of Erb?s palsy?
Waiters tip deformaty. Arm medially rotated, the forearm is extended and pronated
What is Klumpke?s paralysis?
Lower Brachial Plexus: C8-T1 injury
What is a Bankart lesion?
an injury of the anterior (inferior) glenoid labrum of the shoulder
What is Erb?s palsy?
Upper Brachial Plexus: C5-C6 injured
What is the most common side effect of a shoulder disslocation?
Trapping of the auxillary nerve
What is a common side effect of a trapped auxillary nerve
Loss of sensation in the skin over a small part of the lateral upperÿarmÿ(an area known as the regimental badge/patch)
