Recon Flashcards
Lateral center edge angle for acetabular dysplasia.
Less than 20 deg.
Anterior center edge angle for acetabular dysplasia.
Less than 20 deg.
Anterior center edge angle measured on this radiograph.
False profile.
Definition of alpha angle in FAI.
Angle between center of head to head-neck junction and center of neck midline.
Alpha angle with pistol grip deformity.
Greater than 40 degrees.
Energy expenditure with unilateral hip arthrodesis.
Increased by 30%.
Hip arthrodesis positioning.
Neutral abduction, 20-25 deg flexion.
Most common indication for hip arthrodesis conversion to THA.
Back pain.
Hip function after fusion conversion to THA most dependent on this.
Integrity of abductor complex.
This test needed prior to takedown of hip fusion to THA.
Gluteus medius EMG.
___% of cases of osteonecrosis have bilateral involvement.
50%
These drugs reduce risk of collapse in femoral head AVN.
Bisphosphonates.
Method to reduce cement porosity in TJA.
Vacuum mixing.
Optimal pore size for bone ingrowth.
50-150 micrometers.
Main cause of proximal femur stress shielding.
Modulus of elasticity mismatch between femur and stem.
Femoral stem breakage is caused by this.
Cantilever bending.
Bone deficiency defined as loss of cancellous bone without compromise of main structural bone support.
Cavitary deficiency.
Bone deficiency defined as loss of main bony support.s
Segmental deficiency.
Standard cup for revision THA.
Hemispheric porous cup with screw fixation.
Amount of rim needed for fixation of cup in revision THA.
Two-thirds
Acetabular safe zone for screw fixation.
Posterior superior.
Most common complication after modular bearing exchange after THA.
Dislocation.
Most important bearing wear mechanism.
Adhesive bearing wear.
Factors and cytokines release by activated macrophages in osteolysis (6).
- TNF-alpha
- IL-1
- TGF-beta
- IL-6
- PDGF
- RANKL
Main determinant of number of polyethylene particles generated.
Volumetric wear.
Volumetric wear approximates this shape.
A cylinder.
Linear wear rates in excess of ____ mm/yr are associated with osteolysis.
0.1 mm/yr
Hallmark radiographic finding of osteolysis.
Femoral endosteal scalloping.
Why most late periprosthetic hip fractures occur at stem tip.
Area of greatest modulus mismatch.
Most common reason for intra-op periprosthetic acetabular fracture.
Underreaming.
Most common complication of hip resurfacing.
Fracture.
Treatment of failed hip resurfacing.
Convert to total hip arthroplasty.
Most common mechanism of nerve injury after THA.
Compression.
Sciatic nerve travels closest to acetabulum at level of the _____.
Ischium.