Knee and hip orthopaedics Flashcards
what 2 joints make up the knee
tibiofemoral
patellofemoral
lateral and medial menisci are important for what
joint congruence and shock absorption
function of ACL
prevents anterior tibial subluxation and internal rotation during extension
function of MCL
resists valgus force
function of LCL
resists varus force and external rotation
function of PCL
prevents hyperextension and posterior tibial translation or anterior femur translation
consequence of TKR on a young patient?
may need revision surgery, deemed inferior to primary TKR
when is TKR indicated
pain and disability where conservative management ineffective
how does a meniscal tear classically occur and which meniscus is it
twisting force on a loaded knee or die to ACL rupture
usually medial
what is true knee locking
15 degree spongy block to extension due to bucket handle meniscal tear
what is knee pseudolocking
non-meniscal knee injury - temporary difficulty in straightening joint
how do degenerate meniscus tears occur
older age, thought to be the first stage of OA
what types of meniscal tears should be considered for repair
tears in a younger patient in the outer 1/3
when is a partial menisectomy considered
if pain and inflammation from meniscal injury does not settle following injury
who is indicated for ACL repair
professional athletes or those whos knees give way on sedentary activity despite physio
what causes ACL rupture
high rotational force
what causes PCL rupture
direct blow to anterior knee or hyperextension
indication for isolated PCL rupture repair
ligament laxity, recurrent hyperextension with instability or unstable descending stairs
what causes LCL injury, how is it managed, what type of instability do patients have
varus injury
reconstruction
instability on rotation due to excessive external rotation
what causes MCL injury, how is it managed
valgus stress injury
usually well healing, only requires knee brace with little to no instability
what happens to see complete knee dislocation
all 4 ligaments would have to rupture
compromised popliteal artery and common fibular artery
what must you check following knee dislocation
distal pulses
what extensor mechanism tendon is usually ruptured iun <20
patellar tendon
what extensor mechanism tendon is usually ruptured in >40
quadriceps tendon
risk factors for ruptured extensor mechanism
steriods ciprofloxacin chronic renal failure tendinitis diabetes rheumatoid arthritis
clinical features of patellofemoral dysfunction
adolescents pain going downhill grinding/clicking at front of knee anterior knee pain stiffness/pseudolocking in flexed position
true/false - patellar dislocations are almost always medial
false - theyre almost always lateral
risk factors for patellar dislocation
ligament laxity females valgus deformity shallow trochlear groove high riding patella femoral neck anteversion
rule of thirds in ACL rupture?
1/3 compensate
1/3 avoid instability by avoiding activity
1/3 do not compensate with frequent instability
what is osteochondritis dissecans
area of surface of joint loses blood supply and piece of bone/cartilage fragments
what is bone marrow oedema
impact to articular surface leads to microscopic fracture of trabecular bone with bleeding/inflammation
can take months to repair
why may a loose body in the knee become a problem and how can it be fixed
may cause painful locking/catching or mobile lump iwth occasional pain
may be managed arthroscopically
conservative management of knee pain
explanation support analgesia short term NSAIDS for flare up support physiotherapy steroid injection for acute referral
conservative management of hip pain
education weight reduction home adaptation stick analgesia NSAIDS physiotherapy complementary medicine mobility allowance, disability badge
when to refer for hip pain?
Pain, and pain at night lost function physical/mental fitness support at home patient expectation age of patient uncertain diagnosis
3 patterns of hip pain?
pain in groin
pain in buttock
referred knee pain
signs of hip pathology on examination
lost internal rotation
leg shortening
abductor weakness by +ve trendelenberg
exacerbated pain on rotation
what are other differentials for groin pain beside hip pathology
hernia
tendonitis
high lumbar disc prolapse
pubic symphysis dysfunction
how long does a THA/THR last
cup last 15 years and ball 20
what determines whether someone needs THR
levels of pain and disability failing conservative management
conservative measures for hip pain/disability
analgesia physiotherapy use of stick weight reduction activity modification
early local THR complications
infection
dislocation
leg length discrepancy
nerve injury
early general THR complications
chest infection MI Hypovolaemia/blood loss Cardiac arrest DVT/PE UTI
late local THR complications
dislocation
late infection
early loosening
why are hip revision surgeries more difficulty
higher blood loss
more complicated
poorer outcome
dont last as long
why should you delay a young person getting a THR
theyll need a revision surgery
risk factors/epidemiology for AVN
males 35-50 alcohol abuse steroids thrombophilia hyperlipidaemia decompression sickness
how is AVN managed if detected early?
drill holes up femoral neck and head to relieve pressure and to promote healing and prevent collapse
what can you do with the hip once avascular necrosis has occurred
replace it with THR
how does AVN appear on X ray
patchy sclerosis of weight bearing femoral head with a lytic zone beneath
“hanging rope sign”
what is gluteal cuff syndrome/trochanteric bursitis
tendinous insertion of gluteal muscles in greater trochanter is subject to tendonitis
trochanteric bursa may become inflamed
what primary and secondary factors may lead to knee osteoarthritis
obesity older age genetics work/hobbies meniscal tear trauma ACL rupture malalignment heavy workload
when would TKR be considered in a patient
in pain or disability refractory to conservative management
constant pain and limited walking
sleep disturbance
frequent flare up
true/false - 10% of patients who have a TKR have unexplained pain and these patients are usually older
false - 20% do and patients are usually younger, obese, chronic pain syndrome, mild OA in original joint, psychological distress
what is the satisfaction rate of a TR and how long would you expect it to last in an ideal patient
expected to last 15-20 years
75-80% satisfaction
true/false - sport and heavy work may cause TKR to loosen and fial sooner than expected
true
true/false - revision is a more complex surgery but works just as well as TKR
no, it is way more complicated and doesnt work nearly as well
what are surgical options in a failed TKR revision
fusion
amputation
in patients with chronic pain following TKR, would redoing the TKR be expected to work?
no
alternatives to TKR
unicompartmental knee replacement for heavily affected and localised OA of the knee, reop rate is high
osteotomy for younger patients who would trash a TKR, unfavoured
when would you offer a clean out surgery for the knee
never, ever
presentation of avascular necrosis
insidious onset groin pain
exacerbated by stairs/impact
normal examination
conservative management of avascular necrosis
bisphosphonates with core decompression
who is trochanteric bursitis more common in
runners
women
presentation of trochanteric bursitis?
pain on lateral aspect of hip and greater trochanter
management of trochanteric bursitis
analgesia
NSAIDs
physiotherapy
steroid injection
causes of OA of the hip
DDH SUFE Septic arthritis FAI Trauma AVN primary
presentation of OA of hip
groin pain worse on activity pain at night stiff ROM start up pain
what is CAM femoroacetabular impingement syndrome, who is is more common in
femoral deformity with asymmetric head and decreased head/neck ratio
usually young and athletic males and may be related to previous SUFE
what is pincer femoroacetabular impingement syndrome and who is it more common in
acetabular deformity with overhang
more common in females
what actions cause pain in femoroacetabular impingement syndrome
flexion, adduction, internal rotation
presentation of FA impingement syndrome
activity related pain in groin
difficulty sitting
C sign positive
FADIR provocation positive
management of FA impingement syndrome
observe if incidental
manage conservatively
arthroscopic/open removal of CAM or debride labral tears/osteotomy
arthroplasty in older patients
