Injury + Surgery Flashcards
what is the pathogenesis of avascular necrosis of the femoral head?
- increased venous pressure in femoral head
- pressure cuts off arterial supply
what are the 3 zones of cartilage?
superficial zone
transitional zone
deep zone
what is the orientation of the cartilage fibres in the superficial zone?
parallel to the surface
what is the orientation of the cartilage fibres in the transitional zone?
randomly orientated
what is the orientation of the cartilage fibres in the
perpendicular to the surface
what section of the cartilage must the damage reach for healing to occur?
the tidemark
what cartilage type is the hyaline cartilage replaced with during healing?
fibrocartilage
what is protrusio?
when the femur starts to protrude into the acetabulum itself
which is protrusio more common in- RA or OA?
rheumatoid arthritis
what is an osteotomy?
a controlled cut of the bone in order to realign or redistribute weight
what is a CAM bony feature of the hip joint? (abnormal)
a bigger bump of the femoral neck (no normal taper)
what is a pincer bony feature of the hip joint? (abnormal)
extra bone on the lateral side of the acetabulum
what is the surgical treatment of an asymptomatic pincer or CAM feature on a hip joint?
nothing
what is the surgical treatment of a symptomatic pincer or CAM feature on a hip joint?
shaving of the area of bone to reshape
what is the surgical management of early avascular necrosis?
decompression
drill a hole to let pressure escape
what are the 3 main non-surgical managements of an arthritic hip joint?
weight loss
analgesia
physiotherapy
when is proprioception more of an issue- hip or knee replacements?
knee replacements
compare hip arthritis pain to trochanteric bursitis pain?
hip arthritis pain: generalised achy pain, tender over groin
trochanteric bursitis: localised lateral hip pain, not tender over groin
why can only the peripheral 1/3 of a meniscus be expected to heal?
only the peripheral 1/3 has a blood supply
the rest of the meniscus is avascula
compare the medial and lateral menisci in terms of mobility?
medial menisci- fixed
lateral menisci- more mobile
which compartment does the knee mainly pivot on during flexion and extension?
medial compartment
due to the knee mainly pivoting on the medial compartment during flexion and extension, what way does the tibia slightly rotate during each movement?
flexion- slight internal rotation
extension- slight external rotation
why is the medial meniscus under greater stress than the lateral menisci?
because pivoting of the tibia mainly occurs on the medial compartment
which menisci is more likely to tear- medial or lateral?
medial menisci
what ligament in the knee is the main resistor of valgus stress?
medial collateral ligament
what ligament in the knee is the main resistor of varus stress?
lateral collateral ligament
what ligament in the knee is the main resistor of anterior subluxation of the tibia?
anterior cruciate ligament
what ligament in the knee is the main resistor of posterior subluxation of the tibia? (ie anterior subluxation of the femur)
posterior cruciate ligament
what ligament is the main resistor of excessive internal rotation of the tibia?
anterior cruciate ligament
what ligament is the main resistor of hyperextension of the knee?
posterior cruciate ligament
what ligaments are the main resistor of external rotation of the tibia?
posterolateral corner ligaments
what is the posterolateral corner made of
posterior cruciate ligament
lateral collateral ligament
smaller ligaments
popliteus
compare the medial and lateral collateral ligaments in terms of capacity to heal?
MCL- great capacity to heal
LCL- poor capacity to heal
what type of instability may a MCL rupture lead to?
valgus instability
what type of instability may a ACL rupture lead to?
rotatory instability (excessive internal rotation)
what type of instability may a PCL rupture lead to?
recurrent hyperextension
or
instability when descending staids
what type of instability may a posterolateral corner rupture lead to?
varus instability
and
rotatory instability [excessive external rotation]
when must a longitudinal tear in a meniscus be in order to heal?
peripheral
how do younger patients get meniscal tears?
trauma-
sporting injury (usually twisting)
getting up from squatting position
how do older patients get meniscal tears?
atraumatic spontaneous degenerate tears
what are 50% of ACL tears accompanied by?
meniscal tear
what is the investigation of choice for a suspected meniscal tear?
MRI
what main type of meniscal tears do not heal?
radial tears
when do you consider a arthroscopic menisectomy?
for meniscal tear with:
- mechanical symptoms (eg painful catching or locking)
- irreparable tears
- failed meniscal repair
what type of menisci tear can give you an acute locked knee?
bucket handle tear
what is the treatment for acute locked knee due to a bucked handle tear?
urgent surgery
-arthroscopic repair
what will happen to the knee of a patient with acute locked knee if the knee remains locked?
fixed flexion deformity
if the acute locked knee is irreparable, what is the next step to unlock the knee and prevent further damage?
partial menisectomy
what type of patients is surgery for degenerative meniscal tears reserved for?
patients with mechanical symptoms
not solely for pain
what is the grading system of ligament injuries?
grade 1 - sprain, some fibres are torn but all macroscopic structures intact
grade 2 - partial tear, some fascicles disrupted
grade 3 - complete tear
what type of injuries cause MCL tears?
valgus stressing injuries
what is the main treatment of MCL tears?
bracing, early motion and physio
rarely require surgery
what type of injuries cause ACL tears?
twisting injuries
what type of injuries causes LCL tears?
varus stressing injuries
hyperextension injuries
what type of injuries cause PCL tears?
direct blow to anterior tibia
hyperextension injuries
what type of surgery is used for the treatment of an ACL tear?
ACL reconstruction with a graft
ACL repair doesnt work
what is the most commonly used graft for ACL reconstruction?
autograft from hamstringe tendon
how can physiotherapy help to stabilise ACL deficient knees?
builds up the surrounding muscles
what is the ACL rupture rule of thirds?
1/3 patients compensate and are able to function well (no surgery needed)
1/3 patients can avoid instability by avoiding certain activities (no surgery needed)
1/3 patients do not compensate and have freq instability or cannot gt back into high impact sport (surgery might be needed)
what is the role of surgery (ACL reconstruction) in ACL rupture?
consider when:
- rotatory instability does not respond to physiotherapy
- young adult/adolescent
- patient keen on high impact sport
- when a meniscal repair also has to be done
does ACL reconstuction affect future osteoarthritis risk?
if you rupture your ACL you will get osteoarthritic changes within 10 years, regardless of surgery
ACL reconstruction may even accelerate the osteoarthritic process
what nerve is commonly affected in LCL injury?
common fibular (peroneal) nerve [palsy]
what is the treatment for a complete LCL rupture?
urgent repair (within 2-3 weeks)
where does knee pain and bruising occur in a PCL rupture?
popliteal fossa
when does PCL require reconstruction?
if part of a multiligament knee injury
this is more common than isolated PCL ruptures
what are the 3 major complications of knee dislocation?
- popliteal artery tear
- nerve injury (common fibular)
- compartment syndrom
what needs to be done ASAP with a knee dislocation?
emergency reduction
check neurovascular status
why do you only operate on a knee dislocation a few weeks after the trauma?
wounds don’t close so leave fracture blisters
what are the 4 main causes of weakened tendons that can lead to extensor mechanism rupture?
- previous tendonitis
- steroids
- chronic renal failure
- drugs (eg ciprofloxacin)
what is the main clinical test that indicates extensor mechanism rupture?
unable to perform straight leg raise
what is the treatment of extensor mechanism rupture?
surgical repair
what does a pop at the time of knee trauma suggest?
ACL rupture
what does a haemarthrosis (within an hour) within the knee joint suggest?
ACL rupture
what does an effusion (within a day) within the knee joint suggest?
meniscal or chondral injury
why can haemarthrosis cause generalised knee pain?
blood is an irritant to the knee capsule
why does ACL rupture cause a haemarthrosis?
because the ACL has a big blood vessel through it which can rupture
what does knee locking suggest?
bucket handle meniscal tear
what does localised pain on joint line suggest?
meniscal tear
what are the 4 main substances which comprise hyaline cartilage?
water
collagen
proteoglycans
chondrocytes
what type of strength do the proteoglycans provide the hyaline cartilage with?
compressive strength
what type of strength does the collagen provide the hyaline cartilage with?
tensile strength
how do the proteoglycans provide compressive strength to hyaline cartilage?
hydrophillic so attract water and expand like a balloon
what are the 2 main categories of articular cartilage defects?
traumatic
atraumatic
what are the 3 main subgroups of atraumatic articular cartilage defects?
- osteochondritis dissecans
- osteoarthritis
- inflammatory arthritis
what is osteochondritis dissecans?
a joint condition causing necrosis of subchondral bone due to lack of blood supply
the bone and cartilage fragment can then break free and cause pain/hinder joint motion
who most commonly gets osteochondritis dissecans?
adolescence
what is the name of the surgical techniques used for a defect in the articular cartilage (that wont heal itself)?
cartilage regeneration techniques
what are the 4 main cartilage regeneration techniques?
- drilling/ microfracture
- osteochondral autograft/allograft
- mosaicplasty
- membrane-induced autologous chondrocyte implantation (MACI)
what is the purpose of drilling/ microfracture for the treatment of a defect in articular cartilage?
causes bleeding which stimulates stem cells to come in and differentiate into chondroblasts
(cartilage regeneration technique)
what is osteochondral autograft or allograft?
taking cartilage from other areas of the bodyfrom donors
what is mosaicplasty?
taking small fragments of cartialge from low-weight bearing surfaces and inserting them into the bigger section of defective cartilage
which of the cartilage techniques is used in the NHS?
microfracture
simplest and cheapest technique
compare the causes of shoulder pain of a young adult, middle aged adult or elderly adult?
young adult- instability
middle aged- rotator cuff tear or frozen shoulder
elderly- glenohumeral OA
what is impingement syndrome?
when the tendons of the rotator cuff muscles (especially supraspinatus) are compressed within the tight subacromial space during movement producing pain
why does a patient with impingement syndrome typically have a painful arc between 60 to 120 degrees of abduction?
painful as the inflamed area of supraspinatus tendon passes through the subacromial space
what are the 3 main causes of impingement syndrome?
- tendonitis subacromial bursitis
- acromioclavicular OA with inferior osteophyte
- a hooked acromion
what are the 2 clinical tests for suspected impingement syndrome?
painful arc
Hawkins-Kennedy test
what is the first line treatment of impingement syndrome?
NSAIDs
analgesics
physio
subacromial steroid injections
if non-operative management of impingement syndrome is ineffective, what surgical management can be carried out?
subacromial decompression surgery
what is the non-operative management for rotator cuff tears?
physiotherapy and subacromial steroid injections
what is the operative management for rotator cuff tears?
rotator cuff repairs with subacromial decompression
why do rotator cuff repairs fail in a 3rd of patients?
the tendon is usually disease or retracted too far
why do middle aged patients commonly get rotator cuff tears?
because rotator cuff muscles can tear with minimal or no trauma as a consequence of degenerate changes in te etendons
what are the 3 muscles most commonly involved in rotator cuff tears, and which out of theses is the most common?
supraspinatus (most common)
subscapularis
infraspinatus
how are rotator cuff tears confirmed?
ultrasound or MRI
what is frozen shoulder?
when the capsule and glenohumeral ligaments become inflamed and so thicken and contract
(adhesive capsulitis)
what is the principle clinical sign of frozen shoulder?
loss of external rotation
what are the 3 conditions associated with frozen shoulder?
diabetes
hypercholesterolaemia
dupuytren’s disease
how long does frozen shoulder usually last?
18-24 months
pain first, then stiffness
what is acute calcific tendonitis?
calcium deposition in the supraspinatus tendon which causes acute severe shoulder pain
what can you see on xray of acute calcific tendonitis?
calcium deposition in the supraspinatus tendon just proximal to the greater tuberosity
how is acute calcific tendonitis managed?
pain relief- subacromial steroid and local anaesthetic injections
(condition is self-limiting)
what are the 2 types of shoulder instability?
traumatic
atraumatic
in traumatic instability of the shoulder what direction of dislocation mainly occurs?
anterior dislocation
in atraumatic instability of the shoulder what direction of dislocation occurs?
multidirectional
inferior, anterior or posterior
what type of patients get atraumatic instability of the shoulder?
patients with generalised ligamentous laxity
what surgical treatment can be done for a patient with a shoulder dislocation which didn’t stabilise? (ie now has instability)
bankart repair
(open or arthroscopic)
which reattaches the labrum and capsule to the anterior glenoid
what forms the carpal tunnel?
the carpal bones of the wrist and the flexor retinaculum
what nerve passes through the carpal tunnel?
median nerve
what is the cause of carpal tunnel syndrome?
median nerve compression in the carpal tunnel
why can rheumatoid arthritis cause secondary carpal tunnel syndrome?
synovitis causes reduced space which causes compression of the median nerve
why do conditions sch as pregnancy, diabetes, chronic renal failure and hypothyroidism cause secondary carpal tunnel syndrome?
fluid retention which causes compression of the median nerve
who is more affected by carpal tunnel syndrome-F or M?
females
fractures of the wrist/around the wrist can cause carpal tunnel syndrome, what particular fracture is especially likely?
colles fracture
what do patients with carpal tunnel syndrome present with?
parasthesia (tingling), loss of sensation or clumsiness in the median nerve innervated digits (thumb and radial 2.5 fingers)
what are the 2 tests which reproduce the symptoms of carpal tunnel syndrome?
tinel’s test
phalen’s test
what is tinel’s test?
percussing over the median nerve (or ulnar nerve)
if positive, this will reproduce the symptoms of carpal tunnel syndrome (or cubital tunnel syndrome)
what is phalen’s test?
holding the wrists hyper-flexed
if positive this will reproduce the symptoms of carpal tunnel syndrome
how do you confirm the diagnosis of carpal tunnel syndrome?
nerve conduction studies
what are the non-operative ways to manage carpal tunnel syndrome?
night splints to prevent flexion
corticosteroid injections
what is the surgical management of carpal tunnel syndrome?
carpal tunnel decompression
what does carpal tunnel decompression involve?
division of the transverse carpal ligament under local anaesthetic
what is the cause of cubital tunnel syndrome?
compression of the ulnar nerve in the cubital tunnel
what do patients with cubital tunnel syndrome present with?
paraesthesia in the ulnar 1.5 fingers and weakness of the muscles innervated by the ulnar nerve
what tests can be used for detecting cubital tunnel syndrome?
tinel’s test (of cubital tunnel)
froment’s test
what does Froment’s test assess?
weakness of the adductor pollicis
seen in cubital tunnel syndrome
why might there be compression of the ulnar nerve in the cubital tunnel?
due to a tight band of fascia forming over the roof of the tunnel (osborne’s fascia)
or
tightness at the intermuscular septum as the nerve passes between the two heads of flexor carpi ulnaris
how is he diagnosis of cubital tunnel syndrome confirmed?
nerve conduction studies
what causes lateral epicondylitis?
-repetitive strain
-degenerative enthesopathy
causing microtears in common extensor origin
what is an enthesopathy?
inflammation at the origin or insertion of a tendon or ligament into bone
what are the clinical features of lateral epicondylitis?
painful and tender lateral epicondyle
pain on resisted middle finger and wrist extension
what is the treatment of lateral epicondylitis?
usually resolves with: period of rest NSAIDs steroid injections elbow clasp (ultrasound therapy) surgical treatment of refractory cases
what causes medial epicondylitis?
-repetitive strain
-degenerative enthesopathy
causing microtears in comon flexor origin
which is more common- medial or lateral epicondylitis?
lateral epicondylitis
why can steroid injections not be used in the treatment of medial epicondylitis?
risk of ulnar nerve injury when injectinf this area
what is the surgical treatment of RA/OA of the elbow which has failed non-operative management?
surgical excision of the radial head
or
total elbow replacement
what is the major con of total elbow replacement?
lifting weight restriction of 2.5kg
what are dupuytren’s contracture?
a proliferative connective tissue disorder where the specialised palmar fascia undergoes hyperplasia
normal bands form nodules and cords and progress to contractures
which joints are commonly affected in dupuytren’s contractures?
MCP and PIPs of ring finger and little finger
in dupuytren’s contractures, what type of cells proliferate and what abnormal substance do they produce?
myofibroblast cells
abnormal type 3 collagen (should be type 1)
who more commonly gets dupuytren’s contractures- M or F?
males
dupuytren’s contractures can sometimes be familial, what sort of inheritance is it?
autosomal dominant (with variable penetrance)
what condition can dupuytren’s contractures be a feature of?
alcoholic cirrhosis
what drug can dupuytren’s contractures be a side effect of?
phenytoin
what population with a chronic condition is dupuytren’s contractures seen more commonly in than the normal population? (ignoring other fibromatoses)
diabetics
up to what degrees of contracture in dupuytren’s contractures can be tolerated at the MCP and the PIP joints?
MCP can tolerate 30 degrees
PIP readily stiffens (any contracture here is usually an indication for surgery)
what are the indications of surgery for dupuytren’s contractures?
- contractures interfering with function
- PIP joint involvement
what is the surgical treatment of dupuytren’s contractures?
fasciectomy (removal of diseased tissue) or fasciotomy (division of cords) or amputation
what is trigger finger?
tendonitis of a flexor tendon causing a nodular enlargement distal to the A1 fascia pulley of the metacarpal neck
movement of finger causes clicking noise
why does movement of a trigger finger cause clicking?
clicks happen as the nodle catches on and then passes underneath the A1 pulley
why can a trigger finger lock in a flexed position?
nodule passes under the pulley but can go back through on extension
what is the treatment for trigger finger?
steroid injections
surgery for persistent cases (division of A1 pulley to allow tendon to move freely)
what is arthrodesis?
artificial ossification of two bones at a joint (fusion)
what is arthroplasty?
surgery to restore integrity of a joint
an artificial joint can be used, or bones might just be resurfaced
what surgical technique can be done to prevent tendon rupture in a RA patient?
tenosynovecomy (excision of synovial tendon sheath)
what is the surgical treatment for the rupture an extensor tendon to the wrist/fingers in a patient with RA?
tendon transfer joint fusions (repair is not possible)
why do all total hip arthroplasty eventually fail?
due to loosening of the prosthetic components
what is revision hip replacement?
a re-do replacement after a hip replacement has failed
more complex than first time hip replacement
if avascular necrosis of the femur head is detected early (pre-collapse) what is the treatment?
decompression by drilling holes into the abnormal area
if avascular necrosis of the femur head is detected late (collapse) what is the treatment?
only option is total hip replacement
what injury does a direct blow to the anterior tibia with the knee flexed suggest?
PCL rupture
what confirms the diagnosis of a meniscal tear?
MRI
what is the treatment for a traumatic meniscal tear?
- repair (doesn’t usually work)
- partial menisectomy
why should a degenerative meniscal tear not be treated with a menisectomy?
removal of meniscal tissue may cause increase stress on already worn surfaces
how can chronic MCL instbility be treated? (ie MCL hasn’t healed)
MCL tightening or reconstruction with tendon graft
why are regular checks of the foot circulation essential after a knee dislocation?
intimal tears can later thrombose
Vacular stenting or by-pass would be required
in a knee dislocation, what ligaments are torn?
ACL, PCL, MCL and LCL
after prolonged ischamia due to a knee dislocation, what may reperfusion result in? (and how can this be treated)
compartment syndrome
fasciotomy
what is the most likely extensor mechanism of the knee rupture in a patient under 40?
patellar tendon rupture
what is the most likely extensor mechanism of the knee rupture in a patient over 40?
quadriceps tendon rupture
why should steroid injections for tendonitis of the extensor mechanism of the knee be avoided?
high risk of tendon rupture
how do you determine whether the extensor mechanism of the knee is intact?
straight leg raise
what is the treatment of complete or substantial partial tears of the knee? extensor
surgical treatment (tendon repair or reattachment)
what is patellofemoral dysfunction?
a group of disorders of the patellofemoral articulation resulting in anterior knee pain
what is chondromalacia patallae?
softening of the hyaline cartilage around the patella
patellofemoral dysfunction
what exacerbates the anterior knee pain of pseudofemoral dysfunction?
going downhill
what does physiotherapy of pseudofemoral knee dysfunction aim to do?
rebalance quadriceps
strengthens vastus medialis
what type of locking does patellofemoral dysfunction cause?
pseudo-locking
knee acutely stiffens in flexed position
what direction does the patella almost always dislocate in?
lateral direction
what type of fluid builds up within the knee joint after patellar dislocation?
lipo-haemarthrosis
how does the risk of recurrent instability vary with age?
risk decreases as age increases
what is hallux valgis?
a deformity of the great toe where 1st metatarsal moves medially and big toe moves laterally
who is hallux valgis more common in- M or F?
females
why does a bunion form over the medial 1st metatarsal head in hallux valgus?
medial aspect of 1st metatarsal will end up rubbing on shoes resultin in inflamed bursa
what may happen to the second toe with hallux valgus?
1st toe may override it
ulceration and skin break down (due to rubbing)