Arthroplasty Flashcards
Soft tissue releases in a valgus knee
Flexion - popliteus
Extension - IT band
Both - LCL
Soft tissue releases in varus knee
tibial osteophyte removal deep MCL posteromedial corner attachment of the semimembranosus partial superficial MCL
Risks of HO following TKA
male
trauma
obesity
increased osteophyte formation
Initial implant for a charcot knee
hinged
polyethylene wear rates associated with loosening
0.1 mm per year
common complication in patients with sickle cell undergoing THA
femoral canal perforation
what effect does TKA have on your golf game
improves your handicap
position for hip arthrodesis
5deg ER
0 deg Add
20 degrees flexion
number one reason for failure of low friction charnley
acetabular failure
what is the only advantage to a smaller incision for THA
cosmesis
Risk factors for sciatic nerve palsy
DDH female revision limb lengthening post traumatic OA surgeon self-rating the procedure
cell involved in metal on metal debris
lymphocytes
drains are associated with
increased risk of transfusion
AAOS bone loss acetabulum
1 - segmental 2 - cavitary 3 - both 4 - seperation between superior and inferior acetab 5 - arthrodesis
groin pain following THA
psoas tendonistis
cortisone injection
release if normal component
revise acetabular component
risk factors for HO THA
prolonged surgery
soft tissue handling
male
heterotrophic OA
need to wait 6 months following procedure to do resection
best predictor of transfusion post-op
low HgB
indications for revision MOM
component loosing progressive osteolysis large effusion pseudotumor unremitting pain
risk factors for dislocation following THA
female AVN fracture treated with tHA inflammatory OA > 70yo
indications for PS
patellectomy
PCL gone
inflammatory OA
easier to balance
more ROM
easier exposure
advantage of mobile bearing
in theory reduces strain on polyethelene
difficulty with posterior referencing in a valgus knee
internal rotation of the femoral component
what will lead to increased Q angle
internal rotation of the femur internal rotation of the tibia lateralizaiton of the patella medialization of the femur medialization of the tibia
where should you center your tibial component
over the medial 2/3 of the tubercle
normal angles of the knee
distal femur - 6 deg valgus
tibia - 3 deg varus
posterior condyles - 3 deg IR
need to neutralize all these angles when you do your cuts
6 deg off femru
3 deg off tibia
3 deg ER from posterior condyles (be careful of hypoplastic lateral condyle in vaglus knee)
benefits of UKA compared to osteotomy
faster rehabilitation and quicker recovery improved cosmesis higher initial success rate fewer short-term complications lasts longer easier to convert to a TKA
complications of UKA
stress fracture - high level of activity
tibial compoenent loosening - will see on XR
compare lateral UKA to medial UKA
the same
factors associated with elevated metal ion levels in MOM
cup abduction > 55
small femoral head
Strong AAOS recommendations for arthritis of hip or knee
weight loss
physical activity
NSAIDS
tramadol
what form of wear is most important in osteolysis
adhesive wear
main determinant in the number of particles created
volumetric wear
related to the size of the head - increased head is increased wear
factors increasing POLY wear
un-cross linked
thickness
compare wear properties
poly - > 0.1 is associated with osteolysis, macrophage
ceramic - best wear, stripe wear
Metal - smaller particles, lower than poly, lymphocytes
risk factors for supracondylar periprosthetic fractures
Rheumatoid arthritis Parkinson's disease chronic steroid therapy osteopenia female gender
risk of tibial periprosthetic fractures
prior tibial tubercle osteotomy
component loosening
component malposition
insertion of long-stemmed tibial components
